Java Web中Timer的使用方法

来源：互联网发布：股票自动挂单软件编辑：程序博客网时间：2024/06/05 20:58

package com.task;
import java.util.Timer;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
public class TaskManager implements ServletContextListener {

//public static final long INTERVAL = ;
public static final long NO_DELAY = 0;
private long interval = 1000*60*5;
private Timer timer;

public void contextInitialized(ServletContextEvent event) {
timer = new Timer("NavTech Request Task!",true);
timer.schedule(new TrafficInfoQueryTask(),NO_DELAY,interval);
}

public void contextDestroyed(ServletContextEvent event) {
timer.cancel();
}

}

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package com.task;

import java.util.TimerTask;

public class TrafficInfoQueryTask extends TimerTask {

//private static Log log = LogFactory.getLog(TrafficInfoQueryTask.class);
private static boolean isRunning = false;

public void run() {
if (!isRunning) {
isRunning = true;
//start task
Communication.start();
//task is ended
isRunning = false;
} else {
System.out.println("Task Running!");
}
}
}

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通过HttpClient获取服务器的响应数据。

package com.task;
import org.apache.commons.httpclient.*;
import org.apache.commons.httpclient.methods.*;
import org.apache.commons.httpclient.params.HttpMethodParams;
import org.xml.sax.SAXException;

import com.trafficxmlparser.TrafficXmlParser;

import java.io.*;
import javax.xml.parsers.ParserConfigurationException;

public class Communication {

  //private static String url = "http://172.23.176.11:8080/TrafficInfoServer/TrafficInfoServer";

  public static void start() {
// Create an instance of HttpClient.
//HttpClient client = new HttpClient();

   // Create a method instance.
   //PostMethod method = new PostMethod(url);
   DBOperation dbOperation = null;
   try {

   // Execute the method.
/*int statusCode = client.executeMethod(method);

if (statusCode != HttpStatus.SC_OK) {
System.err.println("Method failed: " + method.getStatusLine());
}
*/

// parse the XML file
TrafficXmlParser parser = new TrafficXmlParser();
long startTime = System.currentTimeMillis();
//parser.parse(method.getResponseBodyAsString());
parser.parse(new FileInputStream("D:\\Project\\Document\\RealtimeFlowB14.xml"));
long endtTime = System.currentTimeMillis();

System.out.println("时间为:"+(double)(endtTime-startTime)/1000);
   }
   catch (ParserConfigurationException e1)
   {
// TODO Auto-generated catch block
e1.printStackTrace();
}
   catch (SAXException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
   catch (IOException e)
   {
   e.printStackTrace();
   }
   finally
   {
   // Release the connection.
   // method.releaseConnection();
   }
  }
  private static boolean authenticate()
  {
boolean passAuthen = false;
return passAuthen;
  }
}