userclearerdaemonthread.java

该源码是使用ajax技术实现的一个聊天室功能。如果想对程序进行修改

/*
 * Copyright 2005 Frank W. Zammetti
 *
 * 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.struts.apps.ajaxchat.daemon;


import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts.apps.ajaxchat.AjaxChatConfig;
import org.apache.struts.apps.ajaxchat.dao.AjaxChatDAO;


/**
 * This thread executes every X seconds and checks for inactive users.  If a
 * user is found to be inactive, they are removed from any room they are in,
 * as well as from the app itself.  Inactivity is determined by looking at the
 * lastAJAXRequest field of the user object.  If it is more than X seconds old,
 * the user is considered inactive.
 *
 * @author <a href="mailto:[e-mail]">Frank W. Zammetti</a>
 */
public class UserClearerDaemonThread extends Thread {


  /**
   * Log instance.
   */
  private static Log log = LogFactory.getLog(UserClearerDaemonThread.class);


  /**
   * Main thread run method.
   */
  public void run() {

    while (true) {

      try {

        log.info("UserClearerDaemonThread executing next iteration...");

        // The DAO actually does all the heavy lifting, so give it a call.
        AjaxChatDAO dao = AjaxChatDAO.getInstance();
        dao.removeInactiveUsers();

        // Sleep for X seconds as configured.
        sleep(AjaxChatConfig.getUserInactivitySeconds() * 1000);

      } catch (Exception e) {

        log.error("An exception occurred in UserClearerDaemonThread: " + e);
        e.printStackTrace();

      } // End try

    } // End while

  } // End run()


} // End Class