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package com.sun.security.auth.login;

import javax.security.auth.login.AppConfigurationEntry;
import javax.security.auth.login.Configuration;
import java.net.URI;

// NOTE: As of JDK 8, this class instantiates
// sun.security.provider.ConfigFile.Spi and forwards all methods to that
// implementation. All implementation fixes and enhancements should be made to
// sun.security.provider.ConfigFile.Spi and not this class.
// See JDK-8005117 for more information.

This class represents a default implementation for javax.security.auth.login.Configuration. 
 This object stores the runtime login configuration representation, and is the amalgamation of multiple static login configurations that resides in files. The algorithm for locating the login configuration file(s) and reading their information into this Configuration object is: 


  Loop through the security properties,
  login.config.url.1, login.config.url.2, ...,
  login.config.url.X. Each property value specifies a URL pointing to a login configuration file to be loaded. Read in and load each configuration. 
 The java.lang.System property java.security.auth.login.config may also be set to a URL pointing to another login configuration file (which is the case when a user uses the -D switch at runtime). If this property is defined, and its use is allowed by the security property file (the Security property, policy.allowSystemProperty is set to true),
  also load that login configuration.

  If the java.security.auth.login.config property is defined using
  "==" (rather than "="), then ignore all other specified
  login configurations and only load this configuration.

  If no system or security properties were set, try to read from the file,
  ${user.home}/.java.login.config, where ${user.home} is the value
  represented by the "user.home" System property.

 The configuration syntax supported by this implementation is exactly that syntax specified in the javax.security.auth.login.Configuration class. 
See Also:
LoginContext
security properties/**
 * This class represents a default implementation for
 * {@code javax.security.auth.login.Configuration}.
 *
 * <p> This object stores the runtime login configuration representation,
 * and is the amalgamation of multiple static login
 * configurations that resides in files.
 * The algorithm for locating the login configuration file(s) and reading their
 * information into this {@code Configuration} object is:
 *
 * <ol>
 * <li>
 *   Loop through the security properties,
 *   <i>login.config.url.1</i>, <i>login.config.url.2</i>, ...,
 *   <i>login.config.url.X</i>.
 *   Each property value specifies a {@code URL} pointing to a
 *   login configuration file to be loaded.  Read in and load
 *   each configuration.
 *
 * <li>
 *   The {@code java.lang.System} property
 *   <i>java.security.auth.login.config</i>
 *   may also be set to a {@code URL} pointing to another
 *   login configuration file
 *   (which is the case when a user uses the -D switch at runtime).
 *   If this property is defined, and its use is allowed by the
 *   security property file (the Security property,
 *   <i>policy.allowSystemProperty</i> is set to <i>true</i>),
 *   also load that login configuration.
 *
 * <li>
 *   If the <i>java.security.auth.login.config</i> property is defined using
 *   "==" (rather than "="), then ignore all other specified
 *   login configurations and only load this configuration.
 *
 * <li>
 *   If no system or security properties were set, try to read from the file,
 *   ${user.home}/.java.login.config, where ${user.home} is the value
 *   represented by the "user.home" System property.
 * </ol>
 *
 * <p> The configuration syntax supported by this implementation
 * is exactly that syntax specified in the
 * {@code javax.security.auth.login.Configuration} class.
 *
 * @see javax.security.auth.login.LoginContext
 * @see java.security.Security security properties
 */
public class ConfigFile extends Configuration {

    private final sun.security.provider.ConfigFile.Spi spi;

    
Create a new Configuration object. 
Throws:
SecurityException – if the Configuration can not be initialized/**
     * Create a new {@code Configuration} object.
     *
     * @throws SecurityException if the {@code Configuration} can not be
     *                           initialized
     */
    public ConfigFile() {
        spi = new sun.security.provider.ConfigFile.Spi();
    }

    
Create a new Configuration object from the specified URI. 
Params:
uri – the URI
Throws:
SecurityException – if the Configuration can not be initialized
NullPointerException – if uri is null/**
     * Create a new {@code Configuration} object from the specified {@code URI}.
     *
     * @param uri the {@code URI}
     * @throws SecurityException if the {@code Configuration} can not be
     *                           initialized
     * @throws NullPointerException if {@code uri} is null
     */
    public ConfigFile(URI uri) {
        spi = new sun.security.provider.ConfigFile.Spi(uri);
    }

    
Retrieve an entry from the Configuration using an application name as an index. 
Params:
applicationName – the name used to index the Configuration
Returns:
an array of AppConfigurationEntry which correspond to the stacked configuration of LoginModules for this application, or null if this application has no configured LoginModules./**
     * Retrieve an entry from the {@code Configuration} using an application
     * name as an index.
     *
     * @param applicationName the name used to index the {@code Configuration}
     * @return an array of {@code AppConfigurationEntry} which correspond to
     *         the stacked configuration of {@code LoginModule}s for this
     *         application, or null if this application has no configured
     *         {@code LoginModule}s.
     */
    @Override
    public AppConfigurationEntry[] getAppConfigurationEntry
        (String applicationName) {

        return spi.engineGetAppConfigurationEntry(applicationName);
    }

    
Refresh and reload the Configuration by re-reading all of the login configurations. 
Throws:
SecurityException – if the caller does not have permission to refresh the Configuration/**
     * Refresh and reload the {@code Configuration} by re-reading all of the
     * login configurations.
     *
     * @throws SecurityException if the caller does not have permission
     *                           to refresh the {@code Configuration}
     */
    @Override
    public void refresh() {
        spi.engineRefresh();
    }
}