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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * accompanied this code).
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 *
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package java.security;

import java.io.*;
import java.security.cert.Certificate;
import java.security.cert.X509Certificate;
import java.security.cert.CertificateException;
import java.security.spec.AlgorithmParameterSpec;
import java.util.*;
import javax.crypto.SecretKey;

import javax.security.auth.DestroyFailedException;
import javax.security.auth.callback.*;

import sun.security.util.Debug;

This class represents a storage facility for cryptographic
keys and certificates.
 A KeyStore manages different types of entries. Each type of entry implements the KeyStore.Entry interface. Three basic KeyStore.Entry implementations are provided: 

KeyStore.PrivateKeyEntry
 This type of entry holds a cryptographic PrivateKey, which is optionally stored in a protected format to prevent unauthorized access. It is also accompanied by a certificate chain for the corresponding public key. 
 Private keys and certificate chains are used by a given entity for
self-authentication. Applications for this authentication include software
distribution organizations which sign JAR files as part of releasing
and/or licensing software.
KeyStore.SecretKeyEntry
 This type of entry holds a cryptographic SecretKey, which is optionally stored in a protected format to prevent unauthorized access. 
KeyStore.TrustedCertificateEntry
 This type of entry contains a single public key Certificate belonging to another party. It is called a trusted certificate
because the keystore owner trusts that the public key in the certificate
indeed belongs to the identity identified by the subject (owner)
of the certificate.
This type of entry can be used to authenticate other parties.

 Each entry in a keystore is identified by an "alias" string. In the
case of private keys and their associated certificate chains, these strings
distinguish among the different ways in which the entity may authenticate
itself. For example, the entity may authenticate itself using different
certificate authorities, or using different public key algorithms.
 Whether aliases are case sensitive is implementation dependent. In order
to avoid problems, it is recommended not to use aliases in a KeyStore that
only differ in case.
 Whether keystores are persistent, and the mechanisms used by the
keystore if it is persistent, are not specified here. This allows
use of a variety of techniques for protecting sensitive (e.g., private or
secret) keys. Smart cards or other integrated cryptographic engines
(SafeKeyper) are one option, and simpler mechanisms such as files may also
be used (in a variety of formats).
 Typical ways to request a KeyStore object include
specifying an existing keystore file,
relying on the default type and providing a specific keystore type.

To specify an existing keystore file:
   // get keystore password
   char[] password = getPassword();
   // probe the keystore file and load the keystore entries
   KeyStore ks = KeyStore.getInstance(new File("keyStoreName"), password);
 The system will probe the specified file to determine its keystore type and return a keystore implementation with its entries already loaded. When this approach is used there is no need to call the keystore's load method. 
To rely on the default type:
   KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());

The system will return a keystore implementation for the default type.
To provide a specific keystore type:
     KeyStore ks = KeyStore.getInstance("JKS");

The system will return the most preferred implementation of the
specified keystore type available in the environment.

 Before a keystore can be accessed, it must be loaded (unless it was already loaded during instantiation). 
   KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
   // get user password and file input stream
   char[] password = getPassword();
   try (FileInputStream fis = new FileInputStream("keyStoreName")) {
       ks.load(fis, password);
   }
 To create an empty keystore using the above load method, pass null as the InputStream argument. 
 Once the keystore has been loaded, it is possible
to read existing entries from the keystore, or to write new entries
into the keystore:
   KeyStore.ProtectionParameter protParam =
       new KeyStore.PasswordProtection(password);
   // get my private key
   KeyStore.PrivateKeyEntry pkEntry = (KeyStore.PrivateKeyEntry)
       ks.getEntry("privateKeyAlias", protParam);
   PrivateKey myPrivateKey = pkEntry.getPrivateKey();
   // save my secret key
   javax.crypto.SecretKey mySecretKey;
   KeyStore.SecretKeyEntry skEntry =
       new KeyStore.SecretKeyEntry(mySecretKey);
   ks.setEntry("secretKeyAlias", skEntry, protParam);
   // store away the keystore
   try (FileOutputStream fos = new FileOutputStream("newKeyStoreName")) {
       ks.store(fos, password);
   }

Note that although the same password may be used to
load the keystore, to protect the private key entry,
to protect the secret key entry, and to store the keystore
(as is shown in the sample code above),
different passwords or other protection parameters
may also be used.
 Every implementation of the Java platform is required to support the following standard KeyStore type: 

PKCS12

This type is described in the 
KeyStore section of the
Java Security Standard Algorithm Names Specification.
Consult the release documentation for your implementation to see if any
other types are supported.
Author:
Jan Luehe
See Also:
PrivateKey
SecretKey
Certificate
Since:
1.2/**
 * This class represents a storage facility for cryptographic
 * keys and certificates.
 *
 * <p> A {@code KeyStore} manages different types of entries.
 * Each type of entry implements the {@code KeyStore.Entry} interface.
 * Three basic {@code KeyStore.Entry} implementations are provided:
 *
 * <ul>
 * <li><b>KeyStore.PrivateKeyEntry</b>
 * <p> This type of entry holds a cryptographic {@code PrivateKey},
 * which is optionally stored in a protected format to prevent
 * unauthorized access.  It is also accompanied by a certificate chain
 * for the corresponding public key.
 *
 * <p> Private keys and certificate chains are used by a given entity for
 * self-authentication. Applications for this authentication include software
 * distribution organizations which sign JAR files as part of releasing
 * and/or licensing software.
 *
 * <li><b>KeyStore.SecretKeyEntry</b>
 * <p> This type of entry holds a cryptographic {@code SecretKey},
 * which is optionally stored in a protected format to prevent
 * unauthorized access.
 *
 * <li><b>KeyStore.TrustedCertificateEntry</b>
 * <p> This type of entry contains a single public key {@code Certificate}
 * belonging to another party. It is called a <i>trusted certificate</i>
 * because the keystore owner trusts that the public key in the certificate
 * indeed belongs to the identity identified by the <i>subject</i> (owner)
 * of the certificate.
 *
 * <p>This type of entry can be used to authenticate other parties.
 * </ul>
 *
 * <p> Each entry in a keystore is identified by an "alias" string. In the
 * case of private keys and their associated certificate chains, these strings
 * distinguish among the different ways in which the entity may authenticate
 * itself. For example, the entity may authenticate itself using different
 * certificate authorities, or using different public key algorithms.
 *
 * <p> Whether aliases are case sensitive is implementation dependent. In order
 * to avoid problems, it is recommended not to use aliases in a KeyStore that
 * only differ in case.
 *
 * <p> Whether keystores are persistent, and the mechanisms used by the
 * keystore if it is persistent, are not specified here. This allows
 * use of a variety of techniques for protecting sensitive (e.g., private or
 * secret) keys. Smart cards or other integrated cryptographic engines
 * (SafeKeyper) are one option, and simpler mechanisms such as files may also
 * be used (in a variety of formats).
 *
 * <p> Typical ways to request a KeyStore object include
 * specifying an existing keystore file,
 * relying on the default type and providing a specific keystore type.
 *
 * <ul>
 * <li>To specify an existing keystore file:
 * <pre>
 *    // get keystore password
 *    char[] password = getPassword();
 *
 *    // probe the keystore file and load the keystore entries
 *    KeyStore ks = KeyStore.getInstance(new File("keyStoreName"), password);
 *</pre>
 * The system will probe the specified file to determine its keystore type
 * and return a keystore implementation with its entries already loaded.
 * When this approach is used there is no need to call the keystore's
 * {@link #load(java.io.InputStream, char[]) load} method.
 *
 * <li>To rely on the default type:
 * <pre>
 *    KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
 * </pre>
 * The system will return a keystore implementation for the default type.
 *
 * <li>To provide a specific keystore type:
 * <pre>
 *      KeyStore ks = KeyStore.getInstance("JKS");
 * </pre>
 * The system will return the most preferred implementation of the
 * specified keystore type available in the environment.
 * </ul>
 *
 * <p> Before a keystore can be accessed, it must be
 * {@link #load(java.io.InputStream, char[]) loaded}
 * (unless it was already loaded during instantiation).
 * <pre>
 *    KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
 *
 *    // get user password and file input stream
 *    char[] password = getPassword();
 *
 *    try (FileInputStream fis = new FileInputStream("keyStoreName")) {
 *        ks.load(fis, password);
 *    }
 * </pre>
 *
 * To create an empty keystore using the above {@code load} method,
 * pass {@code null} as the {@code InputStream} argument.
 *
 * <p> Once the keystore has been loaded, it is possible
 * to read existing entries from the keystore, or to write new entries
 * into the keystore:
 * <pre>
 *    KeyStore.ProtectionParameter protParam =
 *        new KeyStore.PasswordProtection(password);
 *
 *    // get my private key
 *    KeyStore.PrivateKeyEntry pkEntry = (KeyStore.PrivateKeyEntry)
 *        ks.getEntry("privateKeyAlias", protParam);
 *    PrivateKey myPrivateKey = pkEntry.getPrivateKey();
 *
 *    // save my secret key
 *    javax.crypto.SecretKey mySecretKey;
 *    KeyStore.SecretKeyEntry skEntry =
 *        new KeyStore.SecretKeyEntry(mySecretKey);
 *    ks.setEntry("secretKeyAlias", skEntry, protParam);
 *
 *    // store away the keystore
 *    try (FileOutputStream fos = new FileOutputStream("newKeyStoreName")) {
 *        ks.store(fos, password);
 *    }
 * </pre>
 *
 * Note that although the same password may be used to
 * load the keystore, to protect the private key entry,
 * to protect the secret key entry, and to store the keystore
 * (as is shown in the sample code above),
 * different passwords or other protection parameters
 * may also be used.
 *
 * <p> Every implementation of the Java platform is required to support
 * the following standard {@code KeyStore} type:
 * <ul>
 * <li>{@code PKCS12}</li>
 * </ul>
 * This type is described in the <a href=
 * "{@docRoot}/../specs/security/standard-names.html#keystore-types">
 * KeyStore section</a> of the
 * Java Security Standard Algorithm Names Specification.
 * Consult the release documentation for your implementation to see if any
 * other types are supported.
 *
 * @author Jan Luehe
 *
 * @see java.security.PrivateKey
 * @see javax.crypto.SecretKey
 * @see java.security.cert.Certificate
 *
 * @since 1.2
 */

public class KeyStore {

    private static final Debug kdebug = Debug.getInstance("keystore");
    private static final Debug pdebug =
                        Debug.getInstance("provider", "Provider");
    private static final boolean skipDebug =
        Debug.isOn("engine=") && !Debug.isOn("keystore");

    /*
     * Constant to lookup in the Security properties file to determine
     * the default keystore type.
     * In the Security properties file, the default keystore type is given as:
     * <pre>
     * keystore.type=jks
     * </pre>
     */
    private static final String KEYSTORE_TYPE = "keystore.type";

    // The keystore type
    private String type;

    // The provider
    private Provider provider;

    // The provider implementation
    private KeyStoreSpi keyStoreSpi;

    // Has this keystore been initialized (loaded)?
    private boolean initialized = false;

    
A marker interface for KeyStore load and store parameters. 
Since:
1.5/**
     * A marker interface for {@code KeyStore}
     * {@link #load(KeyStore.LoadStoreParameter) load}
     * and
     * {@link #store(KeyStore.LoadStoreParameter) store}
     * parameters.
     *
     * @since 1.5
     */
    public static interface LoadStoreParameter {
        
Gets the parameter used to protect keystore data.
Returns:
the parameter used to protect keystore data, or null/**
         * Gets the parameter used to protect keystore data.
         *
         * @return the parameter used to protect keystore data, or null
         */
        public ProtectionParameter getProtectionParameter();
    }

    
A marker interface for keystore protection parameters.
 The information stored in a ProtectionParameter object protects the contents of a keystore. For example, protection parameters may be used to check the integrity of keystore data, or to protect the confidentiality of sensitive keystore data (such as a PrivateKey). 
Since:
1.5/**
     * A marker interface for keystore protection parameters.
     *
     * <p> The information stored in a {@code ProtectionParameter}
     * object protects the contents of a keystore.
     * For example, protection parameters may be used to check
     * the integrity of keystore data, or to protect the
     * confidentiality of sensitive keystore data
     * (such as a {@code PrivateKey}).
     *
     * @since 1.5
     */
    public static interface ProtectionParameter { }

    
A password-based implementation of ProtectionParameter. 
Since:
1.5/**
     * A password-based implementation of {@code ProtectionParameter}.
     *
     * @since 1.5
     */
    public static class PasswordProtection implements
                ProtectionParameter, javax.security.auth.Destroyable {

        private final char[] password;
        private final String protectionAlgorithm;
        private final AlgorithmParameterSpec protectionParameters;
        private volatile boolean destroyed = false;

        
Creates a password parameter.
 The specified password is cloned before it is stored in the new PasswordProtection object. 
Params:
password – the password, which may be null/**
         * Creates a password parameter.
         *
         * <p> The specified {@code password} is cloned before it is stored
         * in the new {@code PasswordProtection} object.
         *
         * @param password the password, which may be {@code null}
         */
        public PasswordProtection(char[] password) {
            this.password = (password == null) ? null : password.clone();
            this.protectionAlgorithm = null;
            this.protectionParameters = null;
        }

        
Creates a password parameter and specifies the protection algorithm
and associated parameters to use when encrypting a keystore entry.
 The specified password is cloned before it is stored in the new PasswordProtection object. 
Params:
password – the password, which may be null
protectionAlgorithm – the encryption algorithm name, for example, PBEWithHmacSHA256AndAES_256. See the Cipher section in the 
Java Security Standard Algorithm Names Specification
    for information about standard encryption algorithm names.
protectionParameters – the encryption algorithm parameter specification, which may be null
Throws:
NullPointerException – if protectionAlgorithm is null
Since:
1.8/**
         * Creates a password parameter and specifies the protection algorithm
         * and associated parameters to use when encrypting a keystore entry.
         * <p>
         * The specified {@code password} is cloned before it is stored in the
         * new {@code PasswordProtection} object.
         *
         * @param password the password, which may be {@code null}
         * @param protectionAlgorithm the encryption algorithm name, for
         *     example, {@code PBEWithHmacSHA256AndAES_256}.
         *     See the Cipher section in the <a href=
         * "{@docRoot}/../specs/security/standard-names.html#cipher-algorithm-names">
         * Java Security Standard Algorithm Names Specification</a>
         *     for information about standard encryption algorithm names.
         * @param protectionParameters the encryption algorithm parameter
         *     specification, which may be {@code null}
         * @throws    NullPointerException if {@code protectionAlgorithm} is
         *     {@code null}
         *
         * @since 1.8
         */
        public PasswordProtection(char[] password, String protectionAlgorithm,
            AlgorithmParameterSpec protectionParameters) {
            if (protectionAlgorithm == null) {
                throw new NullPointerException("invalid null input");
            }
            this.password = (password == null) ? null : password.clone();
            this.protectionAlgorithm = protectionAlgorithm;
            this.protectionParameters = protectionParameters;
        }

        
Gets the name of the protection algorithm.
If none was set then the keystore provider will use its default
protection algorithm.
Returns:
the algorithm name, or null if none was set
Since:
1.8/**
         * Gets the name of the protection algorithm.
         * If none was set then the keystore provider will use its default
         * protection algorithm.
         *
         * @return the algorithm name, or {@code null} if none was set
         *
         * @since 1.8
         */
        public String getProtectionAlgorithm() {
            return protectionAlgorithm;
        }

        
Gets the parameters supplied for the protection algorithm.
Returns:
the algorithm parameter specification, or  null, if none was set
Since:
1.8/**
         * Gets the parameters supplied for the protection algorithm.
         *
         * @return the algorithm parameter specification, or {@code  null},
         *     if none was set
         *
         * @since 1.8
         */
        public AlgorithmParameterSpec getProtectionParameters() {
            return protectionParameters;
        }

        
Gets the password.
Note that this method returns a reference to the password.
If a clone of the array is created it is the caller's
responsibility to zero out the password information
after it is no longer needed.
Throws:
IllegalStateException – if the password has
             been cleared (destroyed)
See Also:
destroy()
Returns:
the password, which may be null/**
         * Gets the password.
         *
         * <p>Note that this method returns a reference to the password.
         * If a clone of the array is created it is the caller's
         * responsibility to zero out the password information
         * after it is no longer needed.
         *
         * @see #destroy()
         * @return the password, which may be {@code null}
         * @throws    IllegalStateException if the password has
         *              been cleared (destroyed)
         */
        public synchronized char[] getPassword() {
            if (destroyed) {
                throw new IllegalStateException("password has been cleared");
            }
            return password;
        }

        
Clears the password.
Throws:
DestroyFailedException – if this method was unable
     to clear the password/**
         * Clears the password.
         *
         * @throws    DestroyFailedException if this method was unable
         *      to clear the password
         */
        public synchronized void destroy() throws DestroyFailedException {
            destroyed = true;
            if (password != null) {
                Arrays.fill(password, ' ');
            }
        }

        
Determines if password has been cleared.
Returns:
true if the password has been cleared, false otherwise/**
         * Determines if password has been cleared.
         *
         * @return true if the password has been cleared, false otherwise
         */
        public synchronized boolean isDestroyed() {
            return destroyed;
        }
    }

    
A ProtectionParameter encapsulating a CallbackHandler.
Since:
1.5/**
     * A ProtectionParameter encapsulating a CallbackHandler.
     *
     * @since 1.5
     */
    public static class CallbackHandlerProtection
            implements ProtectionParameter {

        private final CallbackHandler handler;

        
Constructs a new CallbackHandlerProtection from a
CallbackHandler.
Params:
handler – the CallbackHandler
Throws:
NullPointerException – if handler is null/**
         * Constructs a new CallbackHandlerProtection from a
         * CallbackHandler.
         *
         * @param handler the CallbackHandler
         * @throws    NullPointerException if handler is null
         */
        public CallbackHandlerProtection(CallbackHandler handler) {
            if (handler == null) {
                throw new NullPointerException("handler must not be null");
            }
            this.handler = handler;
        }

        
Returns the CallbackHandler.
Returns:
the CallbackHandler./**
         * Returns the CallbackHandler.
         *
         * @return the CallbackHandler.
         */
        public CallbackHandler getCallbackHandler() {
            return handler;
        }

    }

    
A marker interface for KeyStore entry types. 
Since:
1.5/**
     * A marker interface for {@code KeyStore} entry types.
     *
     * @since 1.5
     */
    public static interface Entry {

        
Retrieves the attributes associated with an entry.
Implementation Requirements:
 The default implementation returns an empty Set.
Returns:
an unmodifiable Set of attributes, possibly empty
Since:
1.8/**
         * Retrieves the attributes associated with an entry.
         *
         * @implSpec
         * The default implementation returns an empty {@code Set}.
         *
         * @return an unmodifiable {@code Set} of attributes, possibly empty
         *
         * @since 1.8
         */
        public default Set<Attribute> getAttributes() {
            return Collections.<Attribute>emptySet();
        }

        
An attribute associated with a keystore entry.
It comprises a name and one or more values.
Since:
1.8/**
         * An attribute associated with a keystore entry.
         * It comprises a name and one or more values.
         *
         * @since 1.8
         */
        public interface Attribute {
            
Returns the attribute's name.
Returns:
the attribute name/**
             * Returns the attribute's name.
             *
             * @return the attribute name
             */
            public String getName();

            
Returns the attribute's value.
Multi-valued attributes encode their values as a single string.
Returns:
the attribute value/**
             * Returns the attribute's value.
             * Multi-valued attributes encode their values as a single string.
             *
             * @return the attribute value
             */
            public String getValue();
        }
    }

    
A KeyStore entry that holds a PrivateKey and corresponding certificate chain. 
Since:
1.5/**
     * A {@code KeyStore} entry that holds a {@code PrivateKey}
     * and corresponding certificate chain.
     *
     * @since 1.5
     */
    public static final class PrivateKeyEntry implements Entry {

        private final PrivateKey privKey;
        private final Certificate[] chain;
        private final Set<Attribute> attributes;

        
Constructs a PrivateKeyEntry with a PrivateKey and corresponding certificate chain. 
 The specified chain is cloned before it is stored in the new PrivateKeyEntry object. 
Params:
privateKey – the PrivateKey
chain – an array of Certificates representing the certificate chain. The chain must be ordered and contain a Certificate at index 0 corresponding to the private key.
Throws:
NullPointerException – if privateKey or chain is null
IllegalArgumentException – if the specified chain has a length of 0, if the specified chain does not contain Certificates of the same type, or if the PrivateKey algorithm does not match the algorithm of the PublicKey in the end entity Certificate (at index 0)/**
         * Constructs a {@code PrivateKeyEntry} with a
         * {@code PrivateKey} and corresponding certificate chain.
         *
         * <p> The specified {@code chain} is cloned before it is stored
         * in the new {@code PrivateKeyEntry} object.
         *
         * @param privateKey the {@code PrivateKey}
         * @param chain an array of {@code Certificate}s
         *      representing the certificate chain.
         *      The chain must be ordered and contain a
         *      {@code Certificate} at index 0
         *      corresponding to the private key.
         *
         * @throws    NullPointerException if
         *      {@code privateKey} or {@code chain}
         *      is {@code null}
         * @throws    IllegalArgumentException if the specified chain has a
         *      length of 0, if the specified chain does not contain
         *      {@code Certificate}s of the same type,
         *      or if the {@code PrivateKey} algorithm
         *      does not match the algorithm of the {@code PublicKey}
         *      in the end entity {@code Certificate} (at index 0)
         */
        public PrivateKeyEntry(PrivateKey privateKey, Certificate[] chain) {
            this(privateKey, chain, Collections.<Attribute>emptySet());
        }

        
Constructs a PrivateKeyEntry with a PrivateKey and corresponding certificate chain and associated entry attributes. 
 The specified chain and attributes are cloned before they are stored in the new PrivateKeyEntry object. 
Params:
privateKey – the PrivateKey
chain – an array of Certificates representing the certificate chain. The chain must be ordered and contain a Certificate at index 0 corresponding to the private key.
attributes – the attributes
Throws:
NullPointerException – if privateKey, chain or attributes is null
IllegalArgumentException – if the specified chain has a length of 0, if the specified chain does not contain Certificates of the same type, or if the PrivateKey algorithm does not match the algorithm of the PublicKey in the end entity Certificate (at index 0)
Since:
1.8/**
         * Constructs a {@code PrivateKeyEntry} with a {@code PrivateKey} and
         * corresponding certificate chain and associated entry attributes.
         *
         * <p> The specified {@code chain} and {@code attributes} are cloned
         * before they are stored in the new {@code PrivateKeyEntry} object.
         *
         * @param privateKey the {@code PrivateKey}
         * @param chain an array of {@code Certificate}s
         *      representing the certificate chain.
         *      The chain must be ordered and contain a
         *      {@code Certificate} at index 0
         *      corresponding to the private key.
         * @param attributes the attributes
         *
         * @throws    NullPointerException if {@code privateKey}, {@code chain}
         *      or {@code attributes} is {@code null}
         * @throws    IllegalArgumentException if the specified chain has a
         *      length of 0, if the specified chain does not contain
         *      {@code Certificate}s of the same type,
         *      or if the {@code PrivateKey} algorithm
         *      does not match the algorithm of the {@code PublicKey}
         *      in the end entity {@code Certificate} (at index 0)
         *
         * @since 1.8
         */
        public PrivateKeyEntry(PrivateKey privateKey, Certificate[] chain,
           Set<Attribute> attributes) {

            if (privateKey == null || chain == null || attributes == null) {
                throw new NullPointerException("invalid null input");
            }
            if (chain.length == 0) {
                throw new IllegalArgumentException
                                ("invalid zero-length input chain");
            }

            Certificate[] clonedChain = chain.clone();
            String certType = clonedChain[0].getType();
            for (int i = 1; i < clonedChain.length; i++) {
                if (!certType.equals(clonedChain[i].getType())) {
                    throw new IllegalArgumentException
                                ("chain does not contain certificates " +
                                "of the same type");
                }
            }
            if (!privateKey.getAlgorithm().equals
                        (clonedChain[0].getPublicKey().getAlgorithm())) {
                throw new IllegalArgumentException
                                ("private key algorithm does not match " +
                                "algorithm of public key in end entity " +
                                "certificate (at index 0)");
            }
            this.privKey = privateKey;

            if (clonedChain[0] instanceof X509Certificate &&
                !(clonedChain instanceof X509Certificate[])) {

                this.chain = new X509Certificate[clonedChain.length];
                System.arraycopy(clonedChain, 0,
                                this.chain, 0, clonedChain.length);
            } else {
                this.chain = clonedChain;
            }

            this.attributes =
                Collections.unmodifiableSet(new HashSet<>(attributes));
        }

        
Gets the PrivateKey from this entry. 
Returns:
the PrivateKey from this entry/**
         * Gets the {@code PrivateKey} from this entry.
         *
         * @return the {@code PrivateKey} from this entry
         */
        public PrivateKey getPrivateKey() {
            return privKey;
        }

        
Gets the Certificate chain from this entry. 
 The stored chain is cloned before being returned.
Returns:
an array of Certificates corresponding to the certificate chain for the public key. If the certificates are of type X.509, the runtime type of the returned array is X509Certificate[]./**
         * Gets the {@code Certificate} chain from this entry.
         *
         * <p> The stored chain is cloned before being returned.
         *
         * @return an array of {@code Certificate}s corresponding
         *      to the certificate chain for the public key.
         *      If the certificates are of type X.509,
         *      the runtime type of the returned array is
         *      {@code X509Certificate[]}.
         */
        public Certificate[] getCertificateChain() {
            return chain.clone();
        }

        
Gets the end entity Certificate from the certificate chain in this entry. 
Returns:
the end entity Certificate (at index 0) from the certificate chain in this entry. If the certificate is of type X.509, the runtime type of the returned certificate is X509Certificate./**
         * Gets the end entity {@code Certificate}
         * from the certificate chain in this entry.
         *
         * @return the end entity {@code Certificate} (at index 0)
         *      from the certificate chain in this entry.
         *      If the certificate is of type X.509,
         *      the runtime type of the returned certificate is
         *      {@code X509Certificate}.
         */
        public Certificate getCertificate() {
            return chain[0];
        }

        
Retrieves the attributes associated with an entry.
Returns:
an unmodifiable Set of attributes, possibly empty
Since:
1.8/**
         * Retrieves the attributes associated with an entry.
         *
         * @return an unmodifiable {@code Set} of attributes, possibly empty
         *
         * @since 1.8
         */
        @Override
        public Set<Attribute> getAttributes() {
            return attributes;
        }

        
Returns a string representation of this PrivateKeyEntry.
Returns:
a string representation of this PrivateKeyEntry./**
         * Returns a string representation of this PrivateKeyEntry.
         * @return a string representation of this PrivateKeyEntry.
         */
        public String toString() {
            StringBuilder sb = new StringBuilder();
            sb.append("Private key entry and certificate chain with "
                + chain.length + " elements:\r\n");
            for (Certificate cert : chain) {
                sb.append(cert);
                sb.append("\r\n");
            }
            return sb.toString();
        }

    }

    
A KeyStore entry that holds a SecretKey. 
Since:
1.5/**
     * A {@code KeyStore} entry that holds a {@code SecretKey}.
     *
     * @since 1.5
     */
    public static final class SecretKeyEntry implements Entry {

        private final SecretKey sKey;
        private final Set<Attribute> attributes;

        
Constructs a SecretKeyEntry with a SecretKey. 
Params:
secretKey – the SecretKey
Throws:
NullPointerException – if secretKey is null/**
         * Constructs a {@code SecretKeyEntry} with a
         * {@code SecretKey}.
         *
         * @param secretKey the {@code SecretKey}
         *
         * @throws    NullPointerException if {@code secretKey}
         *      is {@code null}
         */
        public SecretKeyEntry(SecretKey secretKey) {
            if (secretKey == null) {
                throw new NullPointerException("invalid null input");
            }
            this.sKey = secretKey;
            this.attributes = Collections.<Attribute>emptySet();
        }

        
Constructs a SecretKeyEntry with a SecretKey and associated entry attributes. 
 The specified attributes is cloned before it is stored in the new SecretKeyEntry object. 
Params:
secretKey – the SecretKey
attributes – the attributes
Throws:
NullPointerException – if secretKey or attributes is null
Since:
1.8/**
         * Constructs a {@code SecretKeyEntry} with a {@code SecretKey} and
         * associated entry attributes.
         *
         * <p> The specified {@code attributes} is cloned before it is stored
         * in the new {@code SecretKeyEntry} object.
         *
         * @param secretKey the {@code SecretKey}
         * @param attributes the attributes
         *
         * @throws    NullPointerException if {@code secretKey} or
         *     {@code attributes} is {@code null}
         *
         * @since 1.8
         */
        public SecretKeyEntry(SecretKey secretKey, Set<Attribute> attributes) {

            if (secretKey == null || attributes == null) {
                throw new NullPointerException("invalid null input");
            }
            this.sKey = secretKey;
            this.attributes =
                Collections.unmodifiableSet(new HashSet<>(attributes));
        }

        
Gets the SecretKey from this entry. 
Returns:
the SecretKey from this entry/**
         * Gets the {@code SecretKey} from this entry.
         *
         * @return the {@code SecretKey} from this entry
         */
        public SecretKey getSecretKey() {
            return sKey;
        }

        
Retrieves the attributes associated with an entry.
Returns:
an unmodifiable Set of attributes, possibly empty
Since:
1.8/**
         * Retrieves the attributes associated with an entry.
         *
         * @return an unmodifiable {@code Set} of attributes, possibly empty
         *
         * @since 1.8
         */
        @Override
        public Set<Attribute> getAttributes() {
            return attributes;
        }

        
Returns a string representation of this SecretKeyEntry.
Returns:
a string representation of this SecretKeyEntry./**
         * Returns a string representation of this SecretKeyEntry.
         * @return a string representation of this SecretKeyEntry.
         */
        public String toString() {
            return "Secret key entry with algorithm " + sKey.getAlgorithm();
        }
    }

    
A KeyStore entry that holds a trusted Certificate. 
Since:
1.5/**
     * A {@code KeyStore} entry that holds a trusted
     * {@code Certificate}.
     *
     * @since 1.5
     */
    public static final class TrustedCertificateEntry implements Entry {

        private final Certificate cert;
        private final Set<Attribute> attributes;

        
Constructs a TrustedCertificateEntry with a trusted Certificate. 
Params:
trustedCert – the trusted Certificate
Throws:
NullPointerException – if trustedCert is null/**
         * Constructs a {@code TrustedCertificateEntry} with a
         * trusted {@code Certificate}.
         *
         * @param trustedCert the trusted {@code Certificate}
         *
         * @throws    NullPointerException if
         *      {@code trustedCert} is {@code null}
         */
        public TrustedCertificateEntry(Certificate trustedCert) {
            if (trustedCert == null) {
                throw new NullPointerException("invalid null input");
            }
            this.cert = trustedCert;
            this.attributes = Collections.<Attribute>emptySet();
        }

        
Constructs a TrustedCertificateEntry with a trusted Certificate and associated entry attributes. 
 The specified attributes is cloned before it is stored in the new TrustedCertificateEntry object. 
Params:
trustedCert – the trusted Certificate
attributes – the attributes
Throws:
NullPointerException – if trustedCert or attributes is null
Since:
1.8/**
         * Constructs a {@code TrustedCertificateEntry} with a
         * trusted {@code Certificate} and associated entry attributes.
         *
         * <p> The specified {@code attributes} is cloned before it is stored
         * in the new {@code TrustedCertificateEntry} object.
         *
         * @param trustedCert the trusted {@code Certificate}
         * @param attributes the attributes
         *
         * @throws    NullPointerException if {@code trustedCert} or
         *     {@code attributes} is {@code null}
         *
         * @since 1.8
         */
        public TrustedCertificateEntry(Certificate trustedCert,
           Set<Attribute> attributes) {
            if (trustedCert == null || attributes == null) {
                throw new NullPointerException("invalid null input");
            }
            this.cert = trustedCert;
            this.attributes =
                Collections.unmodifiableSet(new HashSet<>(attributes));
        }

        
Gets the trusted Certficate from this entry. 
Returns:
the trusted Certificate from this entry/**
         * Gets the trusted {@code Certficate} from this entry.
         *
         * @return the trusted {@code Certificate} from this entry
         */
        public Certificate getTrustedCertificate() {
            return cert;
        }

        
Retrieves the attributes associated with an entry.
Returns:
an unmodifiable Set of attributes, possibly empty
Since:
1.8/**
         * Retrieves the attributes associated with an entry.
         *
         * @return an unmodifiable {@code Set} of attributes, possibly empty
         *
         * @since 1.8
         */
        @Override
        public Set<Attribute> getAttributes() {
            return attributes;
        }

        
Returns a string representation of this TrustedCertificateEntry.
Returns:
a string representation of this TrustedCertificateEntry./**
         * Returns a string representation of this TrustedCertificateEntry.
         * @return a string representation of this TrustedCertificateEntry.
         */
        public String toString() {
            return "Trusted certificate entry:\r\n" + cert.toString();
        }
    }

    
Creates a KeyStore object of the given type, and encapsulates the given
provider implementation (SPI object) in it.
Params:
keyStoreSpi – the provider implementation.
provider – the provider.
type – the keystore type./**
     * Creates a KeyStore object of the given type, and encapsulates the given
     * provider implementation (SPI object) in it.
     *
     * @param keyStoreSpi the provider implementation.
     * @param provider the provider.
     * @param type the keystore type.
     */
    protected KeyStore(KeyStoreSpi keyStoreSpi, Provider provider, String type)
    {
        this.keyStoreSpi = keyStoreSpi;
        this.provider = provider;
        this.type = type;

        if (!skipDebug && pdebug != null) {
            pdebug.println("KeyStore." + type.toUpperCase() + " type from: " +
                getProviderName());
        }
    }

    private String getProviderName() {
        return (provider == null) ? "(no provider)" : provider.getName();
    }

    
Returns a keystore object of the specified type.
 This method traverses the list of registered security Providers,
starting with the most preferred Provider.
A new KeyStore object encapsulating the
KeyStoreSpi implementation from the first
Provider that supports the specified type is returned.
 Note that the list of registered providers may be retrieved via the Security.getProviders() method. 
Params:
type – the type of keystore.
See the KeyStore section in the 
Java Security Standard Algorithm Names Specification
for information about standard keystore types.
Throws:
KeyStoreException – if no Provider supports a KeyStoreSpi implementation for the specified type
NullPointerException – if type is null
See Also:
Provider
Implementation Note:
 The JDK Reference Implementation additionally uses the jdk.security.provider.preferred Security property to determine the preferred provider order for the specified algorithm. This may be different than the order of providers returned by Security.getProviders().
Returns:
a keystore object of the specified type/**
     * Returns a keystore object of the specified type.
     *
     * <p> This method traverses the list of registered security Providers,
     * starting with the most preferred Provider.
     * A new KeyStore object encapsulating the
     * KeyStoreSpi implementation from the first
     * Provider that supports the specified type is returned.
     *
     * <p> Note that the list of registered providers may be retrieved via
     * the {@link Security#getProviders() Security.getProviders()} method.
     *
     * @implNote
     * The JDK Reference Implementation additionally uses the
     * {@code jdk.security.provider.preferred}
     * {@link Security#getProperty(String) Security} property to determine
     * the preferred provider order for the specified algorithm. This
     * may be different than the order of providers returned by
     * {@link Security#getProviders() Security.getProviders()}.
     *
     * @param type the type of keystore.
     * See the KeyStore section in the <a href=
     * "{@docRoot}/../specs/security/standard-names.html#keystore-types">
     * Java Security Standard Algorithm Names Specification</a>
     * for information about standard keystore types.
     *
     * @return a keystore object of the specified type
     *
     * @throws KeyStoreException if no {@code Provider} supports a
     *         {@code KeyStoreSpi} implementation for the
     *         specified type
     *
     * @throws NullPointerException if {@code type} is {@code null}
     *
     * @see Provider
     */
    public static KeyStore getInstance(String type)
        throws KeyStoreException
    {
        Objects.requireNonNull(type, "null type name");
        try {
            Object[] objs = Security.getImpl(type, "KeyStore", (String)null);
            return new KeyStore((KeyStoreSpi)objs[0], (Provider)objs[1], type);
        } catch (NoSuchAlgorithmException nsae) {
            throw new KeyStoreException(type + " not found", nsae);
        } catch (NoSuchProviderException nspe) {
            throw new KeyStoreException(type + " not found", nspe);
        }
    }

    
Returns a keystore object of the specified type.
 A new KeyStore object encapsulating the
KeyStoreSpi implementation from the specified provider
is returned.  The specified provider must be registered
in the security provider list.
 Note that the list of registered providers may be retrieved via the Security.getProviders() method. 
Params:
type – the type of keystore.
See the KeyStore section in the 
Java Security Standard Algorithm Names Specification
for information about standard keystore types.
provider – the name of the provider.
Throws:
IllegalArgumentException – if the provider name is null or empty
KeyStoreException – if a KeyStoreSpi implementation for the specified type is not available from the specified provider
NoSuchProviderException – if the specified provider is not
        registered in the security provider list
NullPointerException – if type is null
See Also:
Provider
Returns:
a keystore object of the specified type/**
     * Returns a keystore object of the specified type.
     *
     * <p> A new KeyStore object encapsulating the
     * KeyStoreSpi implementation from the specified provider
     * is returned.  The specified provider must be registered
     * in the security provider list.
     *
     * <p> Note that the list of registered providers may be retrieved via
     * the {@link Security#getProviders() Security.getProviders()} method.
     *
     * @param type the type of keystore.
     * See the KeyStore section in the <a href=
     * "{@docRoot}/../specs/security/standard-names.html#keystore-types">
     * Java Security Standard Algorithm Names Specification</a>
     * for information about standard keystore types.
     *
     * @param provider the name of the provider.
     *
     * @return a keystore object of the specified type
     *
     * @throws IllegalArgumentException if the provider name is {@code null}
     *         or empty
     *
     * @throws KeyStoreException if a {@code KeyStoreSpi}
     *         implementation for the specified type is not
     *         available from the specified provider
     *
     * @throws NoSuchProviderException if the specified provider is not
     *         registered in the security provider list
     *
     * @throws NullPointerException if {@code type} is {@code null}
     *
     * @see Provider
     */
    public static KeyStore getInstance(String type, String provider)
        throws KeyStoreException, NoSuchProviderException
    {
        Objects.requireNonNull(type, "null type name");
        if (provider == null || provider.isEmpty())
            throw new IllegalArgumentException("missing provider");
        try {
            Object[] objs = Security.getImpl(type, "KeyStore", provider);
            return new KeyStore((KeyStoreSpi)objs[0], (Provider)objs[1], type);
        } catch (NoSuchAlgorithmException nsae) {
            throw new KeyStoreException(type + " not found", nsae);
        }
    }

    
Returns a keystore object of the specified type.
 A new KeyStore object encapsulating the
KeyStoreSpi implementation from the specified Provider
object is returned.  Note that the specified Provider object
does not have to be registered in the provider list.
Params:
type – the type of keystore.
See the KeyStore section in the 
Java Security Standard Algorithm Names Specification
for information about standard keystore types.
provider – the provider.
Throws:
IllegalArgumentException – if the specified provider is null
KeyStoreException – if KeyStoreSpi implementation for the specified type is not available from the specified Provider object
NullPointerException – if type is null
See Also:
Provider
Returns:
a keystore object of the specified type
Since:
1.4/**
     * Returns a keystore object of the specified type.
     *
     * <p> A new KeyStore object encapsulating the
     * KeyStoreSpi implementation from the specified Provider
     * object is returned.  Note that the specified Provider object
     * does not have to be registered in the provider list.
     *
     * @param type the type of keystore.
     * See the KeyStore section in the <a href=
     * "{@docRoot}/../specs/security/standard-names.html#keystore-types">
     * Java Security Standard Algorithm Names Specification</a>
     * for information about standard keystore types.
     *
     * @param provider the provider.
     *
     * @return a keystore object of the specified type
     *
     * @throws IllegalArgumentException if the specified provider is
     *         {@code null}
     *
     * @throws KeyStoreException if {@code KeyStoreSpi}
     *         implementation for the specified type is not available
     *         from the specified {@code Provider} object
     *
     * @throws NullPointerException if {@code type} is {@code null}
     *
     * @see Provider
     *
     * @since 1.4
     */
    public static KeyStore getInstance(String type, Provider provider)
        throws KeyStoreException
    {
        Objects.requireNonNull(type, "null type name");
        if (provider == null)
            throw new IllegalArgumentException("missing provider");
        try {
            Object[] objs = Security.getImpl(type, "KeyStore", provider);
            return new KeyStore((KeyStoreSpi)objs[0], (Provider)objs[1], type);
        } catch (NoSuchAlgorithmException nsae) {
            throw new KeyStoreException(type + " not found", nsae);
        }
    }

    
Returns the default keystore type as specified by the keystore.type security property, or the string "jks" (acronym for "Java keystore") if no such property exists. 
The default keystore type can be used by applications that do not want to use a hard-coded keystore type when calling one of the getInstance methods, and want to provide a default keystore type in case a user does not specify its own. 
The default keystore type can be changed by setting the value of the keystore.type security property to the desired keystore type. 
See Also:
security properties
Returns:
the default keystore type as specified by the keystore.type security property, or the string "jks" if no such property exists./**
     * Returns the default keystore type as specified by the
     * {@code keystore.type} security property, or the string
     * {@literal "jks"} (acronym for {@literal "Java keystore"})
     * if no such property exists.
     *
     * <p>The default keystore type can be used by applications that do not
     * want to use a hard-coded keystore type when calling one of the
     * {@code getInstance} methods, and want to provide a default keystore
     * type in case a user does not specify its own.
     *
     * <p>The default keystore type can be changed by setting the value of the
     * {@code keystore.type} security property to the desired keystore type.
     *
     * @return the default keystore type as specified by the
     * {@code keystore.type} security property, or the string {@literal "jks"}
     * if no such property exists.
     * @see java.security.Security security properties
     */
    public static final String getDefaultType() {
        String kstype;
        kstype = AccessController.doPrivileged(new PrivilegedAction<>() {
            public String run() {
                return Security.getProperty(KEYSTORE_TYPE);
            }
        });
        if (kstype == null) {
            kstype = "jks";
        }
        return kstype;
    }

    
Returns the provider of this keystore.
Returns:
the provider of this keystore./**
     * Returns the provider of this keystore.
     *
     * @return the provider of this keystore.
     */
    public final Provider getProvider()
    {
        return this.provider;
    }

    
Returns the type of this keystore.
Returns:
the type of this keystore./**
     * Returns the type of this keystore.
     *
     * @return the type of this keystore.
     */
    public final String getType()
    {
        return this.type;
    }

    
Returns the key associated with the given alias, using the given password to recover it. The key must have been associated with the alias by a call to setKeyEntry, or by a call to setEntry with a PrivateKeyEntry or SecretKeyEntry. 
Params:
alias – the alias name
password – the password for recovering the key
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
NoSuchAlgorithmException – if the algorithm for recovering the
key cannot be found
UnrecoverableKeyException – if the key cannot be recovered
(e.g., the given password is wrong).
Returns:
the requested key, or null if the given alias does not exist
or does not identify a key-related entry./**
     * Returns the key associated with the given alias, using the given
     * password to recover it.  The key must have been associated with
     * the alias by a call to {@code setKeyEntry},
     * or by a call to {@code setEntry} with a
     * {@code PrivateKeyEntry} or {@code SecretKeyEntry}.
     *
     * @param alias the alias name
     * @param password the password for recovering the key
     *
     * @return the requested key, or null if the given alias does not exist
     * or does not identify a key-related entry.
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     * @throws    NoSuchAlgorithmException if the algorithm for recovering the
     * key cannot be found
     * @throws    UnrecoverableKeyException if the key cannot be recovered
     * (e.g., the given password is wrong).
     */
    public final Key getKey(String alias, char[] password)
        throws KeyStoreException, NoSuchAlgorithmException,
            UnrecoverableKeyException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineGetKey(alias, password);
    }

    
Returns the certificate chain associated with the given alias. The certificate chain must have been associated with the alias by a call to setKeyEntry, or by a call to setEntry with a PrivateKeyEntry. 
Params:
alias – the alias name
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
the certificate chain (ordered with the user's certificate first
followed by zero or more certificate authorities), or null if the given alias
does not exist or does not contain a certificate chain/**
     * Returns the certificate chain associated with the given alias.
     * The certificate chain must have been associated with the alias
     * by a call to {@code setKeyEntry},
     * or by a call to {@code setEntry} with a
     * {@code PrivateKeyEntry}.
     *
     * @param alias the alias name
     *
     * @return the certificate chain (ordered with the user's certificate first
     * followed by zero or more certificate authorities), or null if the given alias
     * does not exist or does not contain a certificate chain
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final Certificate[] getCertificateChain(String alias)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineGetCertificateChain(alias);
    }

    
Returns the certificate associated with the given alias.
 If the given alias name identifies an entry created by a call to setCertificateEntry, or created by a call to setEntry with a TrustedCertificateEntry, then the trusted certificate contained in that entry is returned. 
 If the given alias name identifies an entry created by a call to setKeyEntry, or created by a call to setEntry with a PrivateKeyEntry, then the first element of the certificate chain in that entry is returned. 
Params:
alias – the alias name
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
the certificate, or null if the given alias does not exist or
does not contain a certificate./**
     * Returns the certificate associated with the given alias.
     *
     * <p> If the given alias name identifies an entry
     * created by a call to {@code setCertificateEntry},
     * or created by a call to {@code setEntry} with a
     * {@code TrustedCertificateEntry},
     * then the trusted certificate contained in that entry is returned.
     *
     * <p> If the given alias name identifies an entry
     * created by a call to {@code setKeyEntry},
     * or created by a call to {@code setEntry} with a
     * {@code PrivateKeyEntry},
     * then the first element of the certificate chain in that entry
     * is returned.
     *
     * @param alias the alias name
     *
     * @return the certificate, or null if the given alias does not exist or
     * does not contain a certificate.
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final Certificate getCertificate(String alias)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineGetCertificate(alias);
    }

    
Returns the creation date of the entry identified by the given alias.
Params:
alias – the alias name
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
the creation date of this entry, or null if the given alias does
not exist/**
     * Returns the creation date of the entry identified by the given alias.
     *
     * @param alias the alias name
     *
     * @return the creation date of this entry, or null if the given alias does
     * not exist
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final Date getCreationDate(String alias)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineGetCreationDate(alias);
    }

    
Assigns the given key to the given alias, protecting it with the given
password.
If the given key is of type java.security.PrivateKey, it must be accompanied by a certificate chain certifying the corresponding public key. 
If the given alias already exists, the keystore information
associated with it is overridden by the given key (and possibly
certificate chain).
Params:
alias – the alias name
key – the key to be associated with the alias
password – the password to protect the key
chain – the certificate chain for the corresponding public key (only required if the given key is of type java.security.PrivateKey).
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded), the given key cannot be protected, or this operation fails
for some other reason/**
     * Assigns the given key to the given alias, protecting it with the given
     * password.
     *
     * <p>If the given key is of type {@code java.security.PrivateKey},
     * it must be accompanied by a certificate chain certifying the
     * corresponding public key.
     *
     * <p>If the given alias already exists, the keystore information
     * associated with it is overridden by the given key (and possibly
     * certificate chain).
     *
     * @param alias the alias name
     * @param key the key to be associated with the alias
     * @param password the password to protect the key
     * @param chain the certificate chain for the corresponding public
     * key (only required if the given key is of type
     * {@code java.security.PrivateKey}).
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded), the given key cannot be protected, or this operation fails
     * for some other reason
     */
    public final void setKeyEntry(String alias, Key key, char[] password,
                                  Certificate[] chain)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        if ((key instanceof PrivateKey) &&
            (chain == null || chain.length == 0)) {
            throw new IllegalArgumentException("Private key must be "
                                               + "accompanied by certificate "
                                               + "chain");
        }
        keyStoreSpi.engineSetKeyEntry(alias, key, password, chain);
    }

    
Assigns the given key (that has already been protected) to the given
alias.
If the protected key is of type java.security.PrivateKey, it must be accompanied by a certificate chain certifying the corresponding public key. If the underlying keystore implementation is of type jks, key must be encoded as an EncryptedPrivateKeyInfo as defined in the PKCS #8 standard. 
If the given alias already exists, the keystore information
associated with it is overridden by the given key (and possibly
certificate chain).
Params:
alias – the alias name
key – the key (in protected format) to be associated with the alias
chain – the certificate chain for the corresponding public key (only useful if the protected key is of type java.security.PrivateKey).
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded), or if this operation fails for some other reason./**
     * Assigns the given key (that has already been protected) to the given
     * alias.
     *
     * <p>If the protected key is of type
     * {@code java.security.PrivateKey}, it must be accompanied by a
     * certificate chain certifying the corresponding public key. If the
     * underlying keystore implementation is of type {@code jks},
     * {@code key} must be encoded as an
     * {@code EncryptedPrivateKeyInfo} as defined in the PKCS #8 standard.
     *
     * <p>If the given alias already exists, the keystore information
     * associated with it is overridden by the given key (and possibly
     * certificate chain).
     *
     * @param alias the alias name
     * @param key the key (in protected format) to be associated with the alias
     * @param chain the certificate chain for the corresponding public
     *          key (only useful if the protected key is of type
     *          {@code java.security.PrivateKey}).
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded), or if this operation fails for some other reason.
     */
    public final void setKeyEntry(String alias, byte[] key,
                                  Certificate[] chain)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        keyStoreSpi.engineSetKeyEntry(alias, key, chain);
    }

    
Assigns the given trusted certificate to the given alias.
 If the given alias identifies an existing entry created by a call to setCertificateEntry, or created by a call to setEntry with a TrustedCertificateEntry, the trusted certificate in the existing entry is overridden by the given certificate. 
Params:
alias – the alias name
cert – the certificate
Throws:
KeyStoreException – if the keystore has not been initialized,
or the given alias already exists and does not identify an
entry containing a trusted certificate,
or this operation fails for some other reason./**
     * Assigns the given trusted certificate to the given alias.
     *
     * <p> If the given alias identifies an existing entry
     * created by a call to {@code setCertificateEntry},
     * or created by a call to {@code setEntry} with a
     * {@code TrustedCertificateEntry},
     * the trusted certificate in the existing entry
     * is overridden by the given certificate.
     *
     * @param alias the alias name
     * @param cert the certificate
     *
     * @throws    KeyStoreException if the keystore has not been initialized,
     * or the given alias already exists and does not identify an
     * entry containing a trusted certificate,
     * or this operation fails for some other reason.
     */
    public final void setCertificateEntry(String alias, Certificate cert)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        keyStoreSpi.engineSetCertificateEntry(alias, cert);
    }

    
Deletes the entry identified by the given alias from this keystore.
Params:
alias – the alias name
Throws:
KeyStoreException – if the keystore has not been initialized,
or if the entry cannot be removed./**
     * Deletes the entry identified by the given alias from this keystore.
     *
     * @param alias the alias name
     *
     * @throws    KeyStoreException if the keystore has not been initialized,
     * or if the entry cannot be removed.
     */
    public final void deleteEntry(String alias)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        keyStoreSpi.engineDeleteEntry(alias);
    }

    
Lists all the alias names of this keystore.
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
enumeration of the alias names/**
     * Lists all the alias names of this keystore.
     *
     * @return enumeration of the alias names
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final Enumeration<String> aliases()
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineAliases();
    }

    
Checks if the given alias exists in this keystore.
Params:
alias – the alias name
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
true if the alias exists, false otherwise/**
     * Checks if the given alias exists in this keystore.
     *
     * @param alias the alias name
     *
     * @return true if the alias exists, false otherwise
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final boolean containsAlias(String alias)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineContainsAlias(alias);
    }

    
Retrieves the number of entries in this keystore.
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
the number of entries in this keystore/**
     * Retrieves the number of entries in this keystore.
     *
     * @return the number of entries in this keystore
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final int size()
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineSize();
    }

    
Returns true if the entry identified by the given alias was created by a call to setKeyEntry, or created by a call to setEntry with a PrivateKeyEntry or a SecretKeyEntry. 
Params:
alias – the alias for the keystore entry to be checked
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
true if the entry identified by the given alias is a
key-related entry, false otherwise./**
     * Returns true if the entry identified by the given alias
     * was created by a call to {@code setKeyEntry},
     * or created by a call to {@code setEntry} with a
     * {@code PrivateKeyEntry} or a {@code SecretKeyEntry}.
     *
     * @param alias the alias for the keystore entry to be checked
     *
     * @return true if the entry identified by the given alias is a
     * key-related entry, false otherwise.
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final boolean isKeyEntry(String alias)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineIsKeyEntry(alias);
    }

    
Returns true if the entry identified by the given alias was created by a call to setCertificateEntry, or created by a call to setEntry with a TrustedCertificateEntry. 
Params:
alias – the alias for the keystore entry to be checked
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
true if the entry identified by the given alias contains a
trusted certificate, false otherwise./**
     * Returns true if the entry identified by the given alias
     * was created by a call to {@code setCertificateEntry},
     * or created by a call to {@code setEntry} with a
     * {@code TrustedCertificateEntry}.
     *
     * @param alias the alias for the keystore entry to be checked
     *
     * @return true if the entry identified by the given alias contains a
     * trusted certificate, false otherwise.
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final boolean isCertificateEntry(String alias)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineIsCertificateEntry(alias);
    }

    
Returns the (alias) name of the first keystore entry whose certificate
matches the given certificate.
 This method attempts to match the given certificate with each keystore entry. If the entry being considered was created by a call to setCertificateEntry, or created by a call to setEntry with a TrustedCertificateEntry, then the given certificate is compared to that entry's certificate. 
 If the entry being considered was created by a call to setKeyEntry, or created by a call to setEntry with a PrivateKeyEntry, then the given certificate is compared to the first element of that entry's certificate chain. 
Params:
cert – the certificate to match with.
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
Returns:
the alias name of the first entry with a matching certificate,
or null if no such entry exists in this keystore./**
     * Returns the (alias) name of the first keystore entry whose certificate
     * matches the given certificate.
     *
     * <p> This method attempts to match the given certificate with each
     * keystore entry. If the entry being considered was
     * created by a call to {@code setCertificateEntry},
     * or created by a call to {@code setEntry} with a
     * {@code TrustedCertificateEntry},
     * then the given certificate is compared to that entry's certificate.
     *
     * <p> If the entry being considered was
     * created by a call to {@code setKeyEntry},
     * or created by a call to {@code setEntry} with a
     * {@code PrivateKeyEntry},
     * then the given certificate is compared to the first
     * element of that entry's certificate chain.
     *
     * @param cert the certificate to match with.
     *
     * @return the alias name of the first entry with a matching certificate,
     * or null if no such entry exists in this keystore.
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     */
    public final String getCertificateAlias(Certificate cert)
        throws KeyStoreException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineGetCertificateAlias(cert);
    }

    
Stores this keystore to the given output stream, and protects its
integrity with the given password.
Params:
stream – the output stream to which this keystore is written.
password – the password to generate the keystore integrity check
Throws:
KeyStoreException – if the keystore has not been initialized
(loaded).
IOException – if there was an I/O problem with data
NoSuchAlgorithmException – if the appropriate data integrity
algorithm could not be found
CertificateException – if any of the certificates included in
the keystore data could not be stored/**
     * Stores this keystore to the given output stream, and protects its
     * integrity with the given password.
     *
     * @param stream the output stream to which this keystore is written.
     * @param password the password to generate the keystore integrity check
     *
     * @throws    KeyStoreException if the keystore has not been initialized
     * (loaded).
     * @throws    IOException if there was an I/O problem with data
     * @throws    NoSuchAlgorithmException if the appropriate data integrity
     * algorithm could not be found
     * @throws    CertificateException if any of the certificates included in
     * the keystore data could not be stored
     */
    public final void store(OutputStream stream, char[] password)
        throws KeyStoreException, IOException, NoSuchAlgorithmException,
            CertificateException
    {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        keyStoreSpi.engineStore(stream, password);
    }

    
Stores this keystore using the given LoadStoreParameter. 
Params:
param – the LoadStoreParameter that specifies how to store the keystore, which may be null
Throws:
IllegalArgumentException – if the given LoadStoreParameter input is not recognized
KeyStoreException – if the keystore has not been initialized
         (loaded)
IOException – if there was an I/O problem with data
NoSuchAlgorithmException – if the appropriate data integrity
         algorithm could not be found
CertificateException – if any of the certificates included in
         the keystore data could not be stored
Since:
1.5/**
     * Stores this keystore using the given {@code LoadStoreParameter}.
     *
     * @param param the {@code LoadStoreParameter}
     *          that specifies how to store the keystore,
     *          which may be {@code null}
     *
     * @throws    IllegalArgumentException if the given
     *          {@code LoadStoreParameter}
     *          input is not recognized
     * @throws    KeyStoreException if the keystore has not been initialized
     *          (loaded)
     * @throws    IOException if there was an I/O problem with data
     * @throws    NoSuchAlgorithmException if the appropriate data integrity
     *          algorithm could not be found
     * @throws    CertificateException if any of the certificates included in
     *          the keystore data could not be stored
     *
     * @since 1.5
     */
    public final void store(LoadStoreParameter param)
                throws KeyStoreException, IOException,
                NoSuchAlgorithmException, CertificateException {
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        keyStoreSpi.engineStore(param);
    }

    
Loads this KeyStore from the given input stream.
A password may be given to unlock the keystore
(e.g. the keystore resides on a hardware token device),
or to check the integrity of the keystore data.
If a password is not given for integrity checking,
then integrity checking is not performed.
In order to create an empty keystore, or if the keystore cannot be initialized from a stream, pass null as the stream argument. 
 Note that if this keystore has already been loaded, it is
reinitialized and loaded again from the given input stream.
Params:
stream – the input stream from which the keystore is loaded, or null
password – the password used to check the integrity of the keystore, the password used to unlock the keystore, or null
Throws:
IOException – if there is an I/O or format problem with the keystore data, if a password is required but not given, or if the given password was incorrect. If the error is due to a wrong password, the cause of the IOException should be an UnrecoverableKeyException
NoSuchAlgorithmException – if the algorithm used to check
the integrity of the keystore cannot be found
CertificateException – if any of the certificates in the
keystore could not be loaded/**
     * Loads this KeyStore from the given input stream.
     *
     * <p>A password may be given to unlock the keystore
     * (e.g. the keystore resides on a hardware token device),
     * or to check the integrity of the keystore data.
     * If a password is not given for integrity checking,
     * then integrity checking is not performed.
     *
     * <p>In order to create an empty keystore, or if the keystore cannot
     * be initialized from a stream, pass {@code null}
     * as the {@code stream} argument.
     *
     * <p> Note that if this keystore has already been loaded, it is
     * reinitialized and loaded again from the given input stream.
     *
     * @param stream the input stream from which the keystore is loaded,
     * or {@code null}
     * @param password the password used to check the integrity of
     * the keystore, the password used to unlock the keystore,
     * or {@code null}
     *
     * @throws    IOException if there is an I/O or format problem with the
     * keystore data, if a password is required but not given,
     * or if the given password was incorrect. If the error is due to a
     * wrong password, the {@link Throwable#getCause cause} of the
     * {@code IOException} should be an
     * {@code UnrecoverableKeyException}
     * @throws    NoSuchAlgorithmException if the algorithm used to check
     * the integrity of the keystore cannot be found
     * @throws    CertificateException if any of the certificates in the
     * keystore could not be loaded
     */
    public final void load(InputStream stream, char[] password)
        throws IOException, NoSuchAlgorithmException, CertificateException
    {
        keyStoreSpi.engineLoad(stream, password);
        initialized = true;
    }

    
Loads this keystore using the given LoadStoreParameter. 
 Note that if this KeyStore has already been loaded, it is
reinitialized and loaded again from the given parameter.
Params:
param – the LoadStoreParameter that specifies how to load the keystore, which may be null
Throws:
IllegalArgumentException – if the given LoadStoreParameter input is not recognized
IOException – if there is an I/O or format problem with the keystore data. If the error is due to an incorrect ProtectionParameter (e.g. wrong password) the cause of the IOException should be an UnrecoverableKeyException
NoSuchAlgorithmException – if the algorithm used to check
         the integrity of the keystore cannot be found
CertificateException – if any of the certificates in the
         keystore could not be loaded
Since:
1.5/**
     * Loads this keystore using the given {@code LoadStoreParameter}.
     *
     * <p> Note that if this KeyStore has already been loaded, it is
     * reinitialized and loaded again from the given parameter.
     *
     * @param param the {@code LoadStoreParameter}
     *          that specifies how to load the keystore,
     *          which may be {@code null}
     *
     * @throws    IllegalArgumentException if the given
     *          {@code LoadStoreParameter}
     *          input is not recognized
     * @throws    IOException if there is an I/O or format problem with the
     *          keystore data. If the error is due to an incorrect
     *         {@code ProtectionParameter} (e.g. wrong password)
     *         the {@link Throwable#getCause cause} of the
     *         {@code IOException} should be an
     *         {@code UnrecoverableKeyException}
     * @throws    NoSuchAlgorithmException if the algorithm used to check
     *          the integrity of the keystore cannot be found
     * @throws    CertificateException if any of the certificates in the
     *          keystore could not be loaded
     *
     * @since 1.5
     */
    public final void load(LoadStoreParameter param)
                throws IOException, NoSuchAlgorithmException,
                CertificateException {

        keyStoreSpi.engineLoad(param);
        initialized = true;
    }

    
Gets a keystore Entry for the specified alias with the specified protection parameter. 
Params:
alias – get the keystore Entry for this alias
protParam – the ProtectionParameter used to protect the Entry, which may be null
Throws:
NullPointerException – if alias is null
NoSuchAlgorithmException – if the algorithm for recovering the
         entry cannot be found
UnrecoverableEntryException – if the specified protParam were insufficient or invalid
UnrecoverableKeyException – if the entry is a PrivateKeyEntry or SecretKeyEntry and the specified protParam does not contain the information needed to recover the key (e.g. wrong password)
KeyStoreException – if the keystore has not been initialized
         (loaded).
See Also:
setEntry(String, Entry, ProtectionParameter)
Returns:
the keystore Entry for the specified alias, or null if there is no such entry
Since:
1.5/**
     * Gets a keystore {@code Entry} for the specified alias
     * with the specified protection parameter.
     *
     * @param alias get the keystore {@code Entry} for this alias
     * @param protParam the {@code ProtectionParameter}
     *          used to protect the {@code Entry},
     *          which may be {@code null}
     *
     * @return the keystore {@code Entry} for the specified alias,
     *          or {@code null} if there is no such entry
     *
     * @throws    NullPointerException if
     *          {@code alias} is {@code null}
     * @throws    NoSuchAlgorithmException if the algorithm for recovering the
     *          entry cannot be found
     * @throws    UnrecoverableEntryException if the specified
     *          {@code protParam} were insufficient or invalid
     * @throws    UnrecoverableKeyException if the entry is a
     *          {@code PrivateKeyEntry} or {@code SecretKeyEntry}
     *          and the specified {@code protParam} does not contain
     *          the information needed to recover the key (e.g. wrong password)
     * @throws    KeyStoreException if the keystore has not been initialized
     *          (loaded).
     * @see #setEntry(String, KeyStore.Entry, KeyStore.ProtectionParameter)
     *
     * @since 1.5
     */
    public final Entry getEntry(String alias, ProtectionParameter protParam)
                throws NoSuchAlgorithmException, UnrecoverableEntryException,
                KeyStoreException {

        if (alias == null) {
            throw new NullPointerException("invalid null input");
        }
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineGetEntry(alias, protParam);
    }

    
Saves a keystore Entry under the specified alias. The protection parameter is used to protect the Entry. 
 If an entry already exists for the specified alias,
it is overridden.
Params:
alias – save the keystore Entry under this alias
entry – the Entry to save
protParam – the ProtectionParameter used to protect the Entry, which may be null
Throws:
NullPointerException – if alias or entry is null
KeyStoreException – if the keystore has not been initialized
         (loaded), or if this operation fails for some other reason
See Also:
getEntry(String, ProtectionParameter)
Since:
1.5/**
     * Saves a keystore {@code Entry} under the specified alias.
     * The protection parameter is used to protect the
     * {@code Entry}.
     *
     * <p> If an entry already exists for the specified alias,
     * it is overridden.
     *
     * @param alias save the keystore {@code Entry} under this alias
     * @param entry the {@code Entry} to save
     * @param protParam the {@code ProtectionParameter}
     *          used to protect the {@code Entry},
     *          which may be {@code null}
     *
     * @throws    NullPointerException if
     *          {@code alias} or {@code entry}
     *          is {@code null}
     * @throws    KeyStoreException if the keystore has not been initialized
     *          (loaded), or if this operation fails for some other reason
     *
     * @see #getEntry(String, KeyStore.ProtectionParameter)
     *
     * @since 1.5
     */
    public final void setEntry(String alias, Entry entry,
                        ProtectionParameter protParam)
                throws KeyStoreException {
        if (alias == null || entry == null) {
            throw new NullPointerException("invalid null input");
        }
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        keyStoreSpi.engineSetEntry(alias, entry, protParam);
    }

    
Determines if the keystore Entry for the specified alias is an instance or subclass of the specified entryClass. 
Params:
alias – the alias name
entryClass – the entry class
Throws:
NullPointerException – if alias or entryClass is null
KeyStoreException – if the keystore has not been
         initialized (loaded)
Returns:
true if the keystore Entry for the specified alias is an instance or subclass of the specified entryClass, false otherwise
Since:
1.5/**
     * Determines if the keystore {@code Entry} for the specified
     * {@code alias} is an instance or subclass of the specified
     * {@code entryClass}.
     *
     * @param alias the alias name
     * @param entryClass the entry class
     *
     * @return true if the keystore {@code Entry} for the specified
     *          {@code alias} is an instance or subclass of the
     *          specified {@code entryClass}, false otherwise
     *
     * @throws    NullPointerException if
     *          {@code alias} or {@code entryClass}
     *          is {@code null}
     * @throws    KeyStoreException if the keystore has not been
     *          initialized (loaded)
     *
     * @since 1.5
     */
    public final boolean
        entryInstanceOf(String alias,
                        Class<? extends KeyStore.Entry> entryClass)
        throws KeyStoreException
    {

        if (alias == null || entryClass == null) {
            throw new NullPointerException("invalid null input");
        }
        if (!initialized) {
            throw new KeyStoreException("Uninitialized keystore");
        }
        return keyStoreSpi.engineEntryInstanceOf(alias, entryClass);
    }

    
Returns a loaded keystore object of the appropriate keystore type.
First the keystore type is determined by probing the specified file.
Then a keystore object is instantiated and loaded using the data from
that file.

A password may be given to unlock the keystore
(e.g. the keystore resides on a hardware token device),
or to check the integrity of the keystore data.
If a password is not given for integrity checking,
then integrity checking is not performed.
 This method traverses the list of registered security providers, starting with the most preferred Provider. For each KeyStoreSpi implementation supported by a Provider, it invokes the engineProbe method to determine if it supports the specified keystore. A new KeyStore object is returned that encapsulates the KeyStoreSpi implementation from the first Provider that supports the specified file. 
 Note that the list of registered providers may be retrieved via the Security.getProviders() method. 
Params:
file – the keystore file
password – the keystore password, which may be null
Throws:
KeyStoreException – if no Provider supports a KeyStoreSpi
            implementation for the specified keystore file.
IOException – if there is an I/O or format problem with the keystore data, if a password is required but not given, or if the given password was incorrect. If the error is due to a wrong password, the cause of the IOException should be an UnrecoverableKeyException.
NoSuchAlgorithmException – if the algorithm used to check the
            integrity of the keystore cannot be found.
CertificateException – if any of the certificates in the
            keystore could not be loaded.
IllegalArgumentException – if file does not exist or does not
            refer to a normal file.
NullPointerException – if file is null.
SecurityException – if a security manager exists and its SecurityManager.checkRead method denies read access to the specified file.
See Also:
Provider
Returns:
a keystore object loaded with keystore data
Since:
9/**
     * Returns a loaded keystore object of the appropriate keystore type.
     * First the keystore type is determined by probing the specified file.
     * Then a keystore object is instantiated and loaded using the data from
     * that file.
     *
     * <p>
     * A password may be given to unlock the keystore
     * (e.g. the keystore resides on a hardware token device),
     * or to check the integrity of the keystore data.
     * If a password is not given for integrity checking,
     * then integrity checking is not performed.
     *
     * <p>
     * This method traverses the list of registered security
     * {@linkplain Provider providers}, starting with the most
     * preferred Provider.
     * For each {@link KeyStoreSpi} implementation supported by a
     * Provider, it invokes the {@link
     * KeyStoreSpi#engineProbe(InputStream) engineProbe} method to
     * determine if it supports the specified keystore.
     * A new KeyStore object is returned that encapsulates the KeyStoreSpi
     * implementation from the first Provider that supports the specified file.
     *
     * <p> Note that the list of registered providers may be retrieved via
     * the {@link Security#getProviders() Security.getProviders()} method.
     *
     * @param  file the keystore file
     * @param  password the keystore password, which may be {@code null}
     *
     * @return a keystore object loaded with keystore data
     *
     * @throws KeyStoreException if no Provider supports a KeyStoreSpi
     *             implementation for the specified keystore file.
     * @throws IOException if there is an I/O or format problem with the
     *             keystore data, if a password is required but not given,
     *             or if the given password was incorrect. If the error is
     *             due to a wrong password, the {@link Throwable#getCause cause}
     *             of the {@code IOException} should be an
     *             {@code UnrecoverableKeyException}.
     * @throws NoSuchAlgorithmException if the algorithm used to check the
     *             integrity of the keystore cannot be found.
     * @throws CertificateException if any of the certificates in the
     *             keystore could not be loaded.
     * @throws IllegalArgumentException if file does not exist or does not
     *             refer to a normal file.
     * @throws NullPointerException if file is {@code null}.
     * @throws SecurityException if a security manager exists and its
     *             {@link java.lang.SecurityManager#checkRead} method denies
     *             read access to the specified file.
     *
     * @see Provider
     *
     * @since 9
     */
    public static final KeyStore getInstance(File file, char[] password)
        throws KeyStoreException, IOException, NoSuchAlgorithmException,
            CertificateException {
        return getInstance(file, password, null, true);
    }

    
Returns a loaded keystore object of the appropriate keystore type. First the keystore type is determined by probing the specified file. Then a keystore object is instantiated and loaded using the data from that file. A LoadStoreParameter may be supplied which specifies how to unlock the keystore data or perform an integrity check. 
 This method traverses the list of registered security providers, starting with the most preferred Provider. For each KeyStoreSpi implementation supported by a Provider, it invokes the engineProbe method to determine if it supports the specified keystore. A new KeyStore object is returned that encapsulates the KeyStoreSpi implementation from the first Provider that supports the specified file. 
 Note that the list of registered providers may be retrieved via the Security.getProviders() method. 
Params:
file – the keystore file
param – the LoadStoreParameter that specifies how to load the keystore, which may be null
Throws:
KeyStoreException – if no Provider supports a KeyStoreSpi
            implementation for the specified keystore file.
IOException – if there is an I/O or format problem with the keystore data. If the error is due to an incorrect ProtectionParameter (e.g. wrong password) the cause of the IOException should be an UnrecoverableKeyException.
NoSuchAlgorithmException – if the algorithm used to check the
            integrity of the keystore cannot be found.
CertificateException – if any of the certificates in the
            keystore could not be loaded.
IllegalArgumentException – if file does not exist or does not
            refer to a normal file, or if param is not recognized.
NullPointerException – if file is null.
SecurityException – if a security manager exists and its SecurityManager.checkRead method denies read access to the specified file.
See Also:
Provider
Returns:
a keystore object loaded with keystore data
Since:
9/**
     * Returns a loaded keystore object of the appropriate keystore type.
     * First the keystore type is determined by probing the specified file.
     * Then a keystore object is instantiated and loaded using the data from
     * that file.
     * A {@code LoadStoreParameter} may be supplied which specifies how to
     * unlock the keystore data or perform an integrity check.
     *
     * <p>
     * This method traverses the list of registered security {@linkplain
     * Provider providers}, starting with the most preferred Provider.
     * For each {@link KeyStoreSpi} implementation supported by a
     * Provider, it invokes the {@link
     * KeyStoreSpi#engineProbe(InputStream) engineProbe} method to
     * determine if it supports the specified keystore.
     * A new KeyStore object is returned that encapsulates the KeyStoreSpi
     * implementation from the first Provider that supports the specified file.
     *
     * <p> Note that the list of registered providers may be retrieved via
     * the {@link Security#getProviders() Security.getProviders()} method.
     *
     * @param  file the keystore file
     * @param  param the {@code LoadStoreParameter} that specifies how to load
     *             the keystore, which may be {@code null}
     *
     * @return a keystore object loaded with keystore data
     *
     * @throws KeyStoreException if no Provider supports a KeyStoreSpi
     *             implementation for the specified keystore file.
     * @throws IOException if there is an I/O or format problem with the
     *             keystore data. If the error is due to an incorrect
     *             {@code ProtectionParameter} (e.g. wrong password)
     *             the {@link Throwable#getCause cause} of the
     *             {@code IOException} should be an
     *             {@code UnrecoverableKeyException}.
     * @throws NoSuchAlgorithmException if the algorithm used to check the
     *             integrity of the keystore cannot be found.
     * @throws CertificateException if any of the certificates in the
     *             keystore could not be loaded.
     * @throws IllegalArgumentException if file does not exist or does not
     *             refer to a normal file, or if param is not recognized.
     * @throws NullPointerException if file is {@code null}.
     * @throws SecurityException if a security manager exists and its
     *             {@link java.lang.SecurityManager#checkRead} method denies
     *             read access to the specified file.
     *
     * @see Provider
     *
     * @since 9
     */
    public static final KeyStore getInstance(File file,
        LoadStoreParameter param) throws KeyStoreException, IOException,
            NoSuchAlgorithmException, CertificateException {
        return getInstance(file, null, param, false);
    }

    // Used by getInstance(File, char[]) & getInstance(File, LoadStoreParameter)
    private static final KeyStore getInstance(File file, char[] password,
        LoadStoreParameter param, boolean hasPassword)
            throws KeyStoreException, IOException, NoSuchAlgorithmException,
                CertificateException {

        if (file == null) {
            throw new NullPointerException();
        }

        if (file.isFile() == false) {
            throw new IllegalArgumentException(
                "File does not exist or it does not refer to a normal file: " +
                    file);
        }

        KeyStore keystore = null;

        try (DataInputStream dataStream =
            new DataInputStream(
                new BufferedInputStream(
                    new FileInputStream(file)))) {

            dataStream.mark(Integer.MAX_VALUE);

            // Detect the keystore type
            for (Provider p : Security.getProviders()) {
                for (Provider.Service s : p.getServices()) {
                    if (s.getType().equals("KeyStore")) {
                        try {
                            KeyStoreSpi impl = (KeyStoreSpi) s.newInstance(null);
                            if (impl.engineProbe(dataStream)) {
                                if (kdebug != null) {
                                    kdebug.println(s.getAlgorithm()
                                            + " keystore detected: " + file);
                                }
                                keystore = new KeyStore(impl, p, s.getAlgorithm());
                                break;
                            }
                        } catch (NoSuchAlgorithmException e) {
                            // ignore
                            if (kdebug != null) {
                                kdebug.println("not found - " + e);
                            }
                        } catch (IOException e) {
                            // ignore
                            if (kdebug != null) {
                                kdebug.println("I/O error in " + file + " - " + e);
                            }
                        }
                        dataStream.reset(); // prepare the stream for the next probe
                    }
                }
            }

            // Load the keystore data
            if (keystore != null) {
                dataStream.reset(); // prepare the stream for loading
                if (hasPassword) {
                    keystore.load(dataStream, password);
                } else {
                    keystore.keyStoreSpi.engineLoad(dataStream, param);
                    keystore.initialized = true;
                }
                return keystore;
            }
        }

        throw new KeyStoreException("Unrecognized keystore format. "
                + "Please load it with a specified type");
    }

    
A description of a to-be-instantiated KeyStore object.
An instance of this class encapsulates the information needed to instantiate and initialize a KeyStore object. That process is triggered when the getKeyStore method is called. 
This makes it possible to decouple configuration from KeyStore
object creation and e.g. delay a password prompt until it is
needed.
See Also:
KeyStore
KeyStoreBuilderParameters
Since:
1.5/**
     * A description of a to-be-instantiated KeyStore object.
     *
     * <p>An instance of this class encapsulates the information needed to
     * instantiate and initialize a KeyStore object. That process is
     * triggered when the {@linkplain #getKeyStore} method is called.
     *
     * <p>This makes it possible to decouple configuration from KeyStore
     * object creation and e.g. delay a password prompt until it is
     * needed.
     *
     * @see KeyStore
     * @see javax.net.ssl.KeyStoreBuilderParameters
     * @since 1.5
     */
    public abstract static class Builder {

        // maximum times to try the callbackhandler if the password is wrong
        static final int MAX_CALLBACK_TRIES = 3;

        
Construct a new Builder.
/**
         * Construct a new Builder.
         */
        protected Builder() {
            // empty
        }

        
Returns the KeyStore described by this object.
Throws:
KeyStoreException – if an error occurred during the
  operation, for example if the KeyStore could not be
  instantiated or loaded
Returns:
the KeyStore described by this object/**
         * Returns the KeyStore described by this object.
         *
         * @return the {@code KeyStore} described by this object
         * @throws    KeyStoreException if an error occurred during the
         *   operation, for example if the KeyStore could not be
         *   instantiated or loaded
         */
        public abstract KeyStore getKeyStore() throws KeyStoreException;

        
Returns the ProtectionParameters that should be used to obtain the Entry with the given alias. The getKeyStore method must be invoked before this method may be called. 
Params:
alias – the alias of the KeyStore entry
Throws:
NullPointerException – if alias is null
KeyStoreException – if an error occurred during the
  operation
IllegalStateException – if the getKeyStore method has
  not been invoked prior to calling this method
Returns:
the ProtectionParameters that should be used to obtain the Entry with the given alias./**
         * Returns the ProtectionParameters that should be used to obtain
         * the {@link KeyStore.Entry Entry} with the given alias.
         * The {@code getKeyStore} method must be invoked before this
         * method may be called.
         *
         * @return the ProtectionParameters that should be used to obtain
         *   the {@link KeyStore.Entry Entry} with the given alias.
         * @param alias the alias of the KeyStore entry
         * @throws NullPointerException if alias is null
         * @throws KeyStoreException if an error occurred during the
         *   operation
         * @throws IllegalStateException if the getKeyStore method has
         *   not been invoked prior to calling this method
         */
        public abstract ProtectionParameter getProtectionParameter(String alias)
            throws KeyStoreException;

        
Returns a new Builder that encapsulates the given KeyStore. The getKeyStore method of the returned object will return keyStore, the getProtectionParameter() method will return protectionParameters. 
 This is useful if an existing KeyStore object needs to be
used with Builder-based APIs.
Params:
keyStore – the KeyStore to be encapsulated
protectionParameter – the ProtectionParameter used to
  protect the KeyStore entries
Throws:
NullPointerException – if keyStore or
  protectionParameters is null
IllegalArgumentException – if the keyStore has not been
  initialized
Returns:
a new Builder object/**
         * Returns a new Builder that encapsulates the given KeyStore.
         * The {@linkplain #getKeyStore} method of the returned object
         * will return {@code keyStore}, the {@linkplain
         * #getProtectionParameter getProtectionParameter()} method will
         * return {@code protectionParameters}.
         *
         * <p> This is useful if an existing KeyStore object needs to be
         * used with Builder-based APIs.
         *
         * @return a new Builder object
         * @param keyStore the KeyStore to be encapsulated
         * @param protectionParameter the ProtectionParameter used to
         *   protect the KeyStore entries
         * @throws NullPointerException if keyStore or
         *   protectionParameters is null
         * @throws IllegalArgumentException if the keyStore has not been
         *   initialized
         */
        public static Builder newInstance(final KeyStore keyStore,
                final ProtectionParameter protectionParameter) {
            if ((keyStore == null) || (protectionParameter == null)) {
                throw new NullPointerException();
            }
            if (keyStore.initialized == false) {
                throw new IllegalArgumentException("KeyStore not initialized");
            }
            return new Builder() {
                private volatile boolean getCalled;

                public KeyStore getKeyStore() {
                    getCalled = true;
                    return keyStore;
                }

                public ProtectionParameter getProtectionParameter(String alias)
                {
                    if (alias == null) {
                        throw new NullPointerException();
                    }
                    if (getCalled == false) {
                        throw new IllegalStateException
                            ("getKeyStore() must be called first");
                    }
                    return protectionParameter;
                }
            };
        }

        
Returns a new Builder object.
The first call to the getKeyStore method on the returned builder will create a KeyStore of type type and call its load() method. The inputStream argument is constructed from file. If protection is a PasswordProtection, the password is obtained by calling the getPassword method. Otherwise, if protection is a CallbackHandlerProtection, the password is obtained by invoking the CallbackHandler. 
Subsequent calls to getKeyStore return the same object as the initial call. If the initial call failed with a KeyStoreException, subsequent calls also throw a KeyStoreException. 
The KeyStore is instantiated from provider if non-null. Otherwise, all installed providers are searched. 
Calls to getProtectionParameter() will return a PasswordProtection object encapsulating the password that was used to invoke the load method. 
Note that the getKeyStore method is executed within the AccessControlContext of the code invoking this method. 
Params:
type – the type of KeyStore to be constructed
provider – the provider from which the KeyStore is to
  be instantiated (or null)
file – the File that contains the KeyStore data
protection – the ProtectionParameter securing the KeyStore data
Throws:
NullPointerException – if type, file or protection is null
IllegalArgumentException – if protection is not an instance
  of either PasswordProtection or CallbackHandlerProtection; or
  if file does not exist or does not refer to a normal file
Returns:
a new Builder object/**
         * Returns a new Builder object.
         *
         * <p>The first call to the {@link #getKeyStore} method on the returned
         * builder will create a KeyStore of type {@code type} and call
         * its {@link KeyStore#load load()} method.
         * The {@code inputStream} argument is constructed from
         * {@code file}.
         * If {@code protection} is a
         * {@code PasswordProtection}, the password is obtained by
         * calling the {@code getPassword} method.
         * Otherwise, if {@code protection} is a
         * {@code CallbackHandlerProtection}, the password is obtained
         * by invoking the CallbackHandler.
         *
         * <p>Subsequent calls to {@link #getKeyStore} return the same object
         * as the initial call. If the initial call failed with a
         * KeyStoreException, subsequent calls also throw a
         * KeyStoreException.
         *
         * <p>The KeyStore is instantiated from {@code provider} if
         * non-null. Otherwise, all installed providers are searched.
         *
         * <p>Calls to {@link #getProtectionParameter getProtectionParameter()}
         * will return a {@link KeyStore.PasswordProtection PasswordProtection}
         * object encapsulating the password that was used to invoke the
         * {@code load} method.
         *
         * <p><em>Note</em> that the {@link #getKeyStore} method is executed
         * within the {@link AccessControlContext} of the code invoking this
         * method.
         *
         * @return a new Builder object
         * @param type the type of KeyStore to be constructed
         * @param provider the provider from which the KeyStore is to
         *   be instantiated (or null)
         * @param file the File that contains the KeyStore data
         * @param protection the ProtectionParameter securing the KeyStore data
         * @throws NullPointerException if type, file or protection is null
         * @throws IllegalArgumentException if protection is not an instance
         *   of either PasswordProtection or CallbackHandlerProtection; or
         *   if file does not exist or does not refer to a normal file
         */
        public static Builder newInstance(String type, Provider provider,
                File file, ProtectionParameter protection) {
            if ((type == null) || (file == null) || (protection == null)) {
                throw new NullPointerException();
            }
            if ((protection instanceof PasswordProtection == false) &&
                (protection instanceof CallbackHandlerProtection == false)) {
                throw new IllegalArgumentException
                ("Protection must be PasswordProtection or " +
                 "CallbackHandlerProtection");
            }
            if (file.isFile() == false) {
                throw new IllegalArgumentException
                    ("File does not exist or it does not refer " +
                     "to a normal file: " + file);
            }
            return new FileBuilder(type, provider, file, protection,
                AccessController.getContext());
        }

        
Returns a new Builder object.
The first call to the getKeyStore method on the returned builder will create a KeyStore using file to detect the keystore type and then call its load() method. It uses the same algorithm to determine the keystore type as described in KeyStore.getInstance(File, LoadStoreParameter). The inputStream argument is constructed from file. If protection is a PasswordProtection, the password is obtained by calling the getPassword method. Otherwise, if protection is a CallbackHandlerProtection, the password is obtained by invoking the CallbackHandler. 
Subsequent calls to getKeyStore return the same object as the initial call. If the initial call failed with a KeyStoreException, subsequent calls also throw a KeyStoreException. 
Calls to getProtectionParameter() will return a PasswordProtection object encapsulating the password that was used to invoke the load method. 
Note that the getKeyStore method is executed within the AccessControlContext of the code invoking this method. 
Params:
file – the File that contains the KeyStore data
protection – the ProtectionParameter securing the KeyStore data
Throws:
NullPointerException – if file or protection is null
IllegalArgumentException – if protection is not an instance
  of either PasswordProtection or CallbackHandlerProtection; or
  if file does not exist or does not refer to a normal file
Returns:
a new Builder object
Since:
9/**
         * Returns a new Builder object.
         *
         * <p>The first call to the {@link #getKeyStore} method on the returned
         * builder will create a KeyStore using {@code file} to detect the
         * keystore type and then call its {@link KeyStore#load load()} method.
         * It uses the same algorithm to determine the keystore type as
         * described in {@link KeyStore#getInstance(File, LoadStoreParameter)}.
         * The {@code inputStream} argument is constructed from {@code file}.
         * If {@code protection} is a {@code PasswordProtection}, the password
         * is obtained by calling the {@code getPassword} method.
         * Otherwise, if {@code protection} is a
         * {@code CallbackHandlerProtection},
         * the password is obtained by invoking the CallbackHandler.
         *
         * <p>Subsequent calls to {@link #getKeyStore} return the same object
         * as the initial call. If the initial call failed with a
         * KeyStoreException, subsequent calls also throw a KeyStoreException.
         *
         * <p>Calls to {@link #getProtectionParameter getProtectionParameter()}
         * will return a {@link KeyStore.PasswordProtection PasswordProtection}
         * object encapsulating the password that was used to invoke the
         * {@code load} method.
         *
         * <p><em>Note</em> that the {@link #getKeyStore} method is executed
         * within the {@link AccessControlContext} of the code invoking this
         * method.
         *
         * @return a new Builder object
         * @param file the File that contains the KeyStore data
         * @param protection the ProtectionParameter securing the KeyStore data
         * @throws NullPointerException if file or protection is null
         * @throws IllegalArgumentException if protection is not an instance
         *   of either PasswordProtection or CallbackHandlerProtection; or
         *   if file does not exist or does not refer to a normal file
         *
         * @since 9
         */
        public static Builder newInstance(File file,
            ProtectionParameter protection) {

            return newInstance("", null, file, protection);
        }

        private static final class FileBuilder extends Builder {

            private final String type;
            private final Provider provider;
            private final File file;
            private ProtectionParameter protection;
            private ProtectionParameter keyProtection;
            private final AccessControlContext context;

            private KeyStore keyStore;

            private Throwable oldException;

            FileBuilder(String type, Provider provider, File file,
                    ProtectionParameter protection,
                    AccessControlContext context) {
                this.type = type;
                this.provider = provider;
                this.file = file;
                this.protection = protection;
                this.context = context;
            }

            public synchronized KeyStore getKeyStore() throws KeyStoreException
            {
                if (keyStore != null) {
                    return keyStore;
                }
                if (oldException != null) {
                    throw new KeyStoreException
                        ("Previous KeyStore instantiation failed",
                         oldException);
                }
                PrivilegedExceptionAction<KeyStore> action =
                        new PrivilegedExceptionAction<KeyStore>() {
                    public KeyStore run() throws Exception {
                        if (protection instanceof CallbackHandlerProtection == false) {
                            return run0();
                        }
                        // when using a CallbackHandler,
                        // reprompt if the password is wrong
                        int tries = 0;
                        while (true) {
                            tries++;
                            try {
                                return run0();
                            } catch (IOException e) {
                                if ((tries < MAX_CALLBACK_TRIES)
                                        && (e.getCause() instanceof UnrecoverableKeyException)) {
                                    continue;
                                }
                                throw e;
                            }
                        }
                    }
                    public KeyStore run0() throws Exception {
                        KeyStore ks;
                        char[] password = null;

                        // Acquire keystore password
                        if (protection instanceof PasswordProtection) {
                            password =
                                ((PasswordProtection)protection).getPassword();
                            keyProtection = protection;
                        } else {
                            CallbackHandler handler =
                                ((CallbackHandlerProtection)protection)
                                    .getCallbackHandler();
                            PasswordCallback callback = new PasswordCallback
                                ("Password for keystore " + file.getName(),
                                    false);
                            handler.handle(new Callback[] {callback});
                            password = callback.getPassword();
                            if (password == null) {
                                throw new KeyStoreException("No password" +
                                                            " provided");
                            }
                            callback.clearPassword();
                            keyProtection = new PasswordProtection(password);
                        }

                        if (type.isEmpty()) {
                            // Instantiate keystore and load keystore data
                            ks = KeyStore.getInstance(file, password);
                        } else {
                            // Instantiate keystore
                            if (provider == null) {
                                ks = KeyStore.getInstance(type);
                            } else {
                                ks = KeyStore.getInstance(type, provider);
                            }
                            // Load keystore data
                            try (InputStream in = new FileInputStream(file)) {
                                ks.load(in, password);
                            }
                        }
                        return ks;
                    }
                };
                try {
                    keyStore = AccessController.doPrivileged(action, context);
                    return keyStore;
                } catch (PrivilegedActionException e) {
                    oldException = e.getCause();
                    throw new KeyStoreException
                        ("KeyStore instantiation failed", oldException);
                }
            }

            public synchronized ProtectionParameter
                        getProtectionParameter(String alias) {
                if (alias == null) {
                    throw new NullPointerException();
                }
                if (keyStore == null) {
                    throw new IllegalStateException
                        ("getKeyStore() must be called first");
                }
                return keyProtection;
            }
        }

        
Returns a new Builder object.
Each call to the getKeyStore method on the returned builder will return a new KeyStore object of type type. Its load() method is invoked using a LoadStoreParameter that encapsulates protection. 
The KeyStore is instantiated from provider if non-null. Otherwise, all installed providers are searched. 
Calls to getProtectionParameter() will return protection. 
Note that the getKeyStore method is executed within the AccessControlContext of the code invoking this method. 
Params:
type – the type of KeyStore to be constructed
provider – the provider from which the KeyStore is to
  be instantiated (or null)
protection – the ProtectionParameter securing the Keystore
Throws:
NullPointerException – if type or protection is null
Returns:
a new Builder object/**
         * Returns a new Builder object.
         *
         * <p>Each call to the {@link #getKeyStore} method on the returned
         * builder will return a new KeyStore object of type {@code type}.
         * Its {@link KeyStore#load(KeyStore.LoadStoreParameter) load()}
         * method is invoked using a
         * {@code LoadStoreParameter} that encapsulates
         * {@code protection}.
         *
         * <p>The KeyStore is instantiated from {@code provider} if
         * non-null. Otherwise, all installed providers are searched.
         *
         * <p>Calls to {@link #getProtectionParameter getProtectionParameter()}
         * will return {@code protection}.
         *
         * <p><em>Note</em> that the {@link #getKeyStore} method is executed
         * within the {@link AccessControlContext} of the code invoking this
         * method.
         *
         * @return a new Builder object
         * @param type the type of KeyStore to be constructed
         * @param provider the provider from which the KeyStore is to
         *   be instantiated (or null)
         * @param protection the ProtectionParameter securing the Keystore
         * @throws NullPointerException if type or protection is null
         */
        public static Builder newInstance(final String type,
                final Provider provider, final ProtectionParameter protection) {
            if ((type == null) || (protection == null)) {
                throw new NullPointerException();
            }
            final AccessControlContext context = AccessController.getContext();
            return new Builder() {
                private volatile boolean getCalled;
                private IOException oldException;

                private final PrivilegedExceptionAction<KeyStore> action
                        = new PrivilegedExceptionAction<KeyStore>() {

                    public KeyStore run() throws Exception {
                        KeyStore ks;
                        if (provider == null) {
                            ks = KeyStore.getInstance(type);
                        } else {
                            ks = KeyStore.getInstance(type, provider);
                        }
                        LoadStoreParameter param = new SimpleLoadStoreParameter(protection);
                        if (protection instanceof CallbackHandlerProtection == false) {
                            ks.load(param);
                        } else {
                            // when using a CallbackHandler,
                            // reprompt if the password is wrong
                            int tries = 0;
                            while (true) {
                                tries++;
                                try {
                                    ks.load(param);
                                    break;
                                } catch (IOException e) {
                                    if (e.getCause() instanceof UnrecoverableKeyException) {
                                        if (tries < MAX_CALLBACK_TRIES) {
                                            continue;
                                        } else {
                                            oldException = e;
                                        }
                                    }
                                    throw e;
                                }
                            }
                        }
                        getCalled = true;
                        return ks;
                    }
                };

                public synchronized KeyStore getKeyStore()
                        throws KeyStoreException {
                    if (oldException != null) {
                        throw new KeyStoreException
                            ("Previous KeyStore instantiation failed",
                             oldException);
                    }
                    try {
                        return AccessController.doPrivileged(action, context);
                    } catch (PrivilegedActionException e) {
                        Throwable cause = e.getCause();
                        throw new KeyStoreException
                            ("KeyStore instantiation failed", cause);
                    }
                }

                public ProtectionParameter getProtectionParameter(String alias)
                {
                    if (alias == null) {
                        throw new NullPointerException();
                    }
                    if (getCalled == false) {
                        throw new IllegalStateException
                            ("getKeyStore() must be called first");
                    }
                    return protection;
                }
            };
        }

    }

    static class SimpleLoadStoreParameter implements LoadStoreParameter {

        private final ProtectionParameter protection;

        SimpleLoadStoreParameter(ProtectionParameter protection) {
            this.protection = protection;
        }

        public ProtectionParameter getProtectionParameter() {
            return protection;
        }
    }
}