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package javax.net.ssl;

import java.security.Security;
import java.security.*;
import java.util.Objects;

import sun.security.jca.GetInstance;

This class acts as a factory for trust managers based on a
source of trust material. Each trust manager manages a specific
type of trust material for use by secure sockets. The trust
material is based on a KeyStore and/or provider-specific sources.
 Every implementation of the Java platform is required to support the following standard TrustManagerFactory algorithm: 

PKIX

This algorithm is described in the 
TrustManagerFactory section of the
Java Security Standard Algorithm Names Specification.
Consult the release documentation for your implementation to see if any
other algorithms are supported.
See Also:
TrustManager
Since:
1.4/**
 * This class acts as a factory for trust managers based on a
 * source of trust material. Each trust manager manages a specific
 * type of trust material for use by secure sockets. The trust
 * material is based on a KeyStore and/or provider-specific sources.
 *
 * <p> Every implementation of the Java platform is required to support the
 * following standard {@code TrustManagerFactory} algorithm:
 * <ul>
 * <li>{@code PKIX}</li>
 * </ul>
 * This algorithm is described in the <a href=
 * "{@docRoot}/../specs/security/standard-names.html#trustmanagerfactory-algorithms">
 * TrustManagerFactory section</a> of the
 * Java Security Standard Algorithm Names Specification.
 * Consult the release documentation for your implementation to see if any
 * other algorithms are supported.
 *
 * @since 1.4
 * @see TrustManager
 */
public class TrustManagerFactory {
    // The provider
    private Provider provider;

    // The provider implementation (delegate)
    private TrustManagerFactorySpi factorySpi;

    // The name of the trust management algorithm.
    private String algorithm;

    
Obtains the default TrustManagerFactory algorithm name.
The default TrustManager can be changed at runtime by setting the value of the ssl.TrustManagerFactory.algorithm security property to the desired algorithm name. 
See Also:
security properties
Returns:
the default algorithm name as specified by the ssl.TrustManagerFactory.algorithm security property, or an implementation-specific default if no such property exists./**
     * Obtains the default TrustManagerFactory algorithm name.
     *
     * <p>The default TrustManager can be changed at runtime by setting
     * the value of the {@code ssl.TrustManagerFactory.algorithm}
     * security property to the desired algorithm name.
     *
     * @see java.security.Security security properties
     * @return the default algorithm name as specified by the
     * {@code ssl.TrustManagerFactory.algorithm} security property, or an
     * implementation-specific default if no such property exists.
     */
    public static final String getDefaultAlgorithm() {
        String type;
        type = AccessController.doPrivileged(new PrivilegedAction<>() {
            @Override
            public String run() {
                return Security.getProperty(
                    "ssl.TrustManagerFactory.algorithm");
            }
        });
        if (type == null) {
            type = "SunX509";
        }
        return type;
    }

    
Creates a TrustManagerFactory object.
Params:
factorySpi – the delegate
provider – the provider
algorithm – the algorithm/**
     * Creates a TrustManagerFactory object.
     *
     * @param factorySpi the delegate
     * @param provider the provider
     * @param algorithm the algorithm
     */
    protected TrustManagerFactory(TrustManagerFactorySpi factorySpi,
            Provider provider, String algorithm) {
        this.factorySpi = factorySpi;
        this.provider = provider;
        this.algorithm = algorithm;
    }

    
Returns the algorithm name of this TrustManagerFactory
object.
This is the same name that was specified in one of the
getInstance calls that created this
TrustManagerFactory object.
Returns:
the algorithm name of this TrustManagerFactory
         object/**
     * Returns the algorithm name of this <code>TrustManagerFactory</code>
     * object.
     *
     * <p>This is the same name that was specified in one of the
     * <code>getInstance</code> calls that created this
     * <code>TrustManagerFactory</code> object.
     *
     * @return the algorithm name of this <code>TrustManagerFactory</code>
     *          object
     */
    public final String getAlgorithm() {
        return this.algorithm;
    }

    
Returns a TrustManagerFactory object that acts as a
factory for trust managers.
 This method traverses the list of registered security Providers,
starting with the most preferred Provider.
A new TrustManagerFactory object encapsulating the
TrustManagerFactorySpi implementation from the first
Provider that supports the specified algorithm is returned.
 Note that the list of registered providers may be retrieved via the Security.getProviders() method. 
Params:
algorithm – the standard name of the requested trust management
         algorithm.  See the 
         TrustManagerFactory section in the Java Security Standard
         Algorithm Names Specification for information about standard
         algorithm names.
Throws:
NoSuchAlgorithmException – if no Provider supports a TrustManagerFactorySpi implementation for the specified algorithm
NullPointerException – if algorithm 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:
the new TrustManagerFactory object/**
     * Returns a <code>TrustManagerFactory</code> object that acts as a
     * factory for trust managers.
     *
     * <p> This method traverses the list of registered security Providers,
     * starting with the most preferred Provider.
     * A new TrustManagerFactory object encapsulating the
     * TrustManagerFactorySpi implementation from the first
     * Provider that supports the specified algorithm 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 algorithm the standard name of the requested trust management
     *          algorithm.  See the <a href=
     *          "{@docRoot}/../specs/security/standard-names.html#trustmanagerfactory-algorithms">
     *          TrustManagerFactory section</a> in the Java Security Standard
     *          Algorithm Names Specification for information about standard
     *          algorithm names.
     *
     * @return the new {@code TrustManagerFactory} object
     *
     * @throws NoSuchAlgorithmException if no {@code Provider} supports a
     *         {@code TrustManagerFactorySpi} implementation for the
     *         specified algorithm
     *
     * @throws NullPointerException if {@code algorithm} is {@code null}
     *
     * @see java.security.Provider
     */
    public static final TrustManagerFactory getInstance(String algorithm)
            throws NoSuchAlgorithmException {
        Objects.requireNonNull(algorithm, "null algorithm name");
        GetInstance.Instance instance = GetInstance.getInstance
                ("TrustManagerFactory", TrustManagerFactorySpi.class,
                algorithm);
        return new TrustManagerFactory((TrustManagerFactorySpi)instance.impl,
                instance.provider, algorithm);
    }

    
Returns a TrustManagerFactory object that acts as a
factory for trust managers.
 A new KeyManagerFactory object encapsulating the
KeyManagerFactorySpi 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:
algorithm – the standard name of the requested trust management
         algorithm.  See the 
         TrustManagerFactory section in the Java Security Standard
         Algorithm Names Specification for information about standard
         algorithm names.
provider – the name of the provider.
Throws:
IllegalArgumentException – if the provider name is null or empty
NoSuchAlgorithmException – if a TrustManagerFactorySpi implementation for the specified algorithm is not available from the specified provider
NoSuchProviderException – if the specified provider is not
        registered in the security provider list
NullPointerException – if algorithm is null
See Also:
Provider
Returns:
the new TrustManagerFactory object/**
     * Returns a <code>TrustManagerFactory</code> object that acts as a
     * factory for trust managers.
     *
     * <p> A new KeyManagerFactory object encapsulating the
     * KeyManagerFactorySpi 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 algorithm the standard name of the requested trust management
     *          algorithm.  See the <a href=
     *          "{@docRoot}/../specs/security/standard-names.html#trustmanagerfactory-algorithms">
     *          TrustManagerFactory section</a> in the Java Security Standard
     *          Algorithm Names Specification for information about standard
     *          algorithm names.
     *
     * @param provider the name of the provider.
     *
     * @return the new {@code TrustManagerFactory} object
     *
     * @throws IllegalArgumentException if the provider name is
     *         {@code null} or empty
     *
     * @throws NoSuchAlgorithmException if a {@code TrustManagerFactorySpi}
     *         implementation for the specified algorithm 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 algorithm} is {@code null}
     *
     * @see java.security.Provider
     */
    public static final TrustManagerFactory getInstance(String algorithm,
            String provider) throws NoSuchAlgorithmException,
            NoSuchProviderException {
        Objects.requireNonNull(algorithm, "null algorithm name");
        GetInstance.Instance instance = GetInstance.getInstance
                ("TrustManagerFactory", TrustManagerFactorySpi.class,
                algorithm, provider);
        return new TrustManagerFactory((TrustManagerFactorySpi)instance.impl,
                instance.provider, algorithm);
    }

    
Returns a TrustManagerFactory object that acts as a
factory for trust managers.
 A new TrustManagerFactory object encapsulating the
TrustManagerFactorySpi 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:
algorithm – the standard name of the requested trust management
         algorithm.  See the 
         TrustManagerFactory section in the Java Security Standard
         Algorithm Names Specification for information about standard
         algorithm names.
provider – an instance of the provider.
Throws:
IllegalArgumentException – if the provider is null
NoSuchAlgorithmException – if a TrustManagerFactorySpi implementation for the specified algorithm is not available from the specified Provider object
NullPointerException – if algorithm is null
See Also:
Provider
Returns:
the new TrustManagerFactory object/**
     * Returns a <code>TrustManagerFactory</code> object that acts as a
     * factory for trust managers.
     *
     * <p> A new TrustManagerFactory object encapsulating the
     * TrustManagerFactorySpi 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 algorithm the standard name of the requested trust management
     *          algorithm.  See the <a href=
     *          "{@docRoot}/../specs/security/standard-names.html#trustmanagerfactory-algorithms">
     *          TrustManagerFactory section</a> in the Java Security Standard
     *          Algorithm Names Specification for information about standard
     *          algorithm names.
     *
     * @param provider an instance of the provider.
     *
     * @return the new {@code TrustManagerFactory} object
     *
     * @throws IllegalArgumentException if the provider is {@code null}
     *
     * @throws NoSuchAlgorithmException if a {@code TrustManagerFactorySpi}
     *         implementation for the specified algorithm is not available
     *         from the specified {@code Provider} object
     *
     * @throws NullPointerException if {@code algorithm} is {@code null}
     *
     * @see java.security.Provider
     */
    public static final TrustManagerFactory getInstance(String algorithm,
            Provider provider) throws NoSuchAlgorithmException {
        Objects.requireNonNull(algorithm, "null algorithm name");
        GetInstance.Instance instance = GetInstance.getInstance
                ("TrustManagerFactory", TrustManagerFactorySpi.class,
                algorithm, provider);
        return new TrustManagerFactory((TrustManagerFactorySpi)instance.impl,
                instance.provider, algorithm);
    }

    
Returns the provider of this TrustManagerFactory object.
Returns:
the provider of this TrustManagerFactory object/**
     * Returns the provider of this <code>TrustManagerFactory</code> object.
     *
     * @return the provider of this <code>TrustManagerFactory</code> object
     */
    public final Provider getProvider() {
        return this.provider;
    }


    
Initializes this factory with a source of certificate
authorities and related trust material.

The provider typically uses a KeyStore as a basis for making
trust decisions.
 For more flexible initialization, please see init(ManagerFactoryParameters). 
Params:
ks – the key store, or null
Throws:
KeyStoreException – if this operation fails/**
     * Initializes this factory with a source of certificate
     * authorities and related trust material.
     * <P>
     * The provider typically uses a KeyStore as a basis for making
     * trust decisions.
     * <P>
     * For more flexible initialization, please see
     * {@link #init(ManagerFactoryParameters)}.
     *
     * @param ks the key store, or null
     * @throws KeyStoreException if this operation fails
     */
    public final void init(KeyStore ks) throws KeyStoreException {
        factorySpi.engineInit(ks);
    }


    
Initializes this factory with a source of provider-specific
trust material.

In some cases, initialization parameters other than a keystore
may be needed by a provider.  Users of that particular provider
are expected to pass an implementation of the appropriate
ManagerFactoryParameters as defined by the
provider.  The provider can then call the specified methods in
the ManagerFactoryParameters implementation to obtain the
needed information.
Params:
spec – an implementation of a provider-specific parameter
         specification
Throws:
InvalidAlgorithmParameterException – if an error is
         encountered/**
     * Initializes this factory with a source of provider-specific
     * trust material.
     * <P>
     * In some cases, initialization parameters other than a keystore
     * may be needed by a provider.  Users of that particular provider
     * are expected to pass an implementation of the appropriate
     * <CODE>ManagerFactoryParameters</CODE> as defined by the
     * provider.  The provider can then call the specified methods in
     * the <CODE>ManagerFactoryParameters</CODE> implementation to obtain the
     * needed information.
     *
     * @param spec an implementation of a provider-specific parameter
     *          specification
     * @throws InvalidAlgorithmParameterException if an error is
     *          encountered
     */
    public final void init(ManagerFactoryParameters spec) throws
            InvalidAlgorithmParameterException {
        factorySpi.engineInit(spec);
    }


    
Returns one trust manager for each type of trust material.
Throws:
IllegalStateException – if the factory is not initialized.
Returns:
the trust managers/**
     * Returns one trust manager for each type of trust material.
     *
     * @throws IllegalStateException if the factory is not initialized.
     *
     * @return the trust managers
     */
    public final TrustManager[] getTrustManagers() {
        return factorySpi.engineGetTrustManagers();
    }
}