/*
 * Copyright 2003-2005 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.wsrp4j.commons.consumer.driver;

import java.util.Hashtable;
import java.util.Iterator;

import org.apache.wsrp4j.commons.consumer.interfaces.user.User;
import org.apache.wsrp4j.commons.consumer.interfaces.user.UserRegistry;

/**
 * @version $Id: GenericUserRegistryImpl.java 327497 2005-08-28 21:35:05Z
 *          dlouzan $
 */
public class GenericUserRegistryImpl implements UserRegistry {

    private Hashtable users;

    public GenericUserRegistryImpl() {
        this.users = new Hashtable();
    }

    /**
     * Get the user with the given id
     * 
     * @param userID
     *            The ID of the user
     * 
     * @return The user
     */
    public User getUser(String userID) {
        if (userID != null) {
            return (User) users.get(userID);
        }

        return null;
    }

    /**
     * Remove a user from the list of known user
     * 
     * @param userID
     *            The ID of the user
     * @return The user which has been removed or null
     */
    public User removeUser(String userID) {
        if (userID == null)
            return null;

        return (User) users.remove(userID);
    }

    /**
     * Add a user. If a record with the given userid already exists, the input
     * UserContext object is returned, otherwise a null value.
     * 
     * @param user
     *            The user object to add
     * 
     * @return Null on success or the input user object in case a user with the
     *         same user id already exists.
     */
    public User addUser(User user) {

        if (user != null) {

            String userID = user.getUserID();
            if (userID != null) {
                if (!users.containsKey(userID)) {
                    users.put(userID, user);

                    return null;
                }
            }
        }

        return user;
    }

    /**
     * Get an iterator with all known users
     * 
     * @return All known user contexts in an iterator
     */
    public Iterator getAllUsers() {
        return users.values().iterator();
    }

    public void removeAllUsers() {
        users.clear();
    }
}