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 * and Distribution License("CDDL") (collectively, the "License").  You
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 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
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 */

package com.sun.enterprise.security;

import java.util.logging.*;
import com.sun.logging.*;


/**
 * This class is used to share information between either of the following scenarios
 * 1. Different points of execution of a single thread
 * 2. Different threads that wish to share the username and password information
 * 
 * Which of the above two condition is applicable depends upon the system property key
 *        "com.sun.appserv.iiopclient.perthreadauth";
 * When set to true, scenario #1 above applies and the username/password 
 * information is not shared between threads.
 * When set to false, scenario #2 above applies and the username/password
 * information stored by one thread is global and visible to all threads.
 */
public final class UsernamePasswordStore {
    
    private static final Logger _logger =
        LogDomains.getLogger(LogDomains.SECURITY_LOGGER);

    private static final boolean isPerThreadAuth = 
            Boolean.getBoolean(ClientSecurityContext.IIOP_CLIENT_PER_THREAD_FLAG);

    private static ThreadLocal localUpc =
        isPerThreadAuth ? new ThreadLocal() : null;
    private static UsernamePasswordStore sharedUpc;

    private final String username;
    private final String password;

    /**
     * This creates a new UsernamePasswordStore object.
     * The constructor is marked as private.
     *
     * @param username
     * @param password
     */
    private UsernamePasswordStore(String username, String password) {
        this.username = username;
        this.password = password;
    }

    /**
     * This method returns a UsernamePasswordStore, that is
     * either thread-local or global depending on the system property
     * IIOP_PER_THREAD_CLIENT_FLAG. 
     * This method is marked as private.
     *
     * @return The current UsernamePasswordStore
     */
    private static UsernamePasswordStore get() {
        if (isPerThreadAuth) {
            return (UsernamePasswordStore) localUpc.get();
        } else {
            synchronized (UsernamePasswordStore.class) {
                return sharedUpc;
            }
        }
    }

    /**
     * This method sets the username and password as thread-local or global variable
     *
     * @param username 
     * @param password
     */
    public static void set(String username, String password) {
        if (isPerThreadAuth) {
            localUpc.set(new UsernamePasswordStore(username, password));
        } else {
            synchronized (UsernamePasswordStore.class) {
                sharedUpc = new UsernamePasswordStore(username, password);
            }
        }
    } 

    /**
     * Clears the username and password, that might have been previously stored,
     * either globally or locally to each thread.
     */
    public static void reset() {
        if (isPerThreadAuth) {
            localUpc.set(null);
        } else {
            synchronized (UsernamePasswordStore.class) {
                sharedUpc = null;
            }
        }
    }
    
    /**
     * Clears the username and password only is they were stored locally
     * to each thread
     */
    public static void resetThreadLocalOnly() {
        if (isPerThreadAuth) {
            localUpc.set(null);
        }
    }

    /**
     * Returns the username, that was previously stored.
     *
     * @return The username set previously or null if not set
     */
    public static String getUsername() {
        UsernamePasswordStore ups = UsernamePasswordStore.get();
        if( ups != null )
            return ups.username;
        else 
            return null;
    }

    
    /**
     * Returns the password, that was previously stored.
     *
     * @return The password set previously or null if not set
     */
    public static String getPassword() {
        UsernamePasswordStore ups = UsernamePasswordStore.get();
        if( ups != null )
            return ups.password;
        else 
            return null;
    }

}