请问怎样实现定时(比如每天5点)执行一次操作? 请问怎样实现定时(比如每天5点)执行一次操作,如到服务器上取下一些文件,请问用什么方法是实现?谢谢!!! 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 用Java定的定时任务,有的时候在执行一些后台任务时很有用listenBean.java import javax.servlet.*;import java.util.*;public class listenerBean implements ServletContextListener { private java.util.Timer timer = null; public void contextInitialized(ServletContextEvent event) { timer = new Timer(true); //定时器已启动 timer.schedule(new MyTask(), 0, (long) 1000*60);//定时1分钟 //已经添加任务调度表 } public void contextDestroyed(ServletContextEvent event) { timer.cancel(); //定时器销毁 }}class MyTask extends TimerTask { private static boolean isRunning = false; public void run() { if (!isRunning) { isRunning = true; //开始执行任务 //ToDo .... //执行任务完成 isRunning = false; } else { //上一次任务执行还未结束 } }}web.xml <web-app> <listener> <listener-class>listenerBean</listener-class></listener></web-app> 我认为用Time来控制就可以了。时间相等就执行操作 在web.xml文件添加后,tomcat启动时报错误:信息: Processing Context configuration file URL file:C:\Program Files\Apache Software Foundation\Tomcat 5.0\conf\Catalina\localhost\balancer.xml2005-12-15 0:11:30 org.apache.catalina.core.StandardContext listenerStart严重: Skipped installing application listeners due to previous error(s)2005-12-15 0:11:30 org.apache.catalina.core.StandardContext start严重: Error listenerStart2005-12-15 0:11:30 org.apache.catalina.core.StandardContext start严重: Context startup failed due to previous errors2005-12-15 0:11:30 org.apache.catalina.core.StandardHostDeployer install信息: Processing Context configuration file URL file:C:\Program Files\Apache Software Foundation\Tomcat 5.0\conf\Catalina\localhost\admin.xml2005-12-15 0:11:31 org.apache.catalina.core.StandardContext listenerStart严重: Skipped installing application listeners due to previous error(s)2005-12-15 0:11:31 org.apache.catalina.core.StandardContext start严重: Error listenerStart2005-12-15 0:11:31 org.apache.catalina.core.StandardContext start严重: Context startup failed due to previous errors2005-12-15 0:11:31 org.apache.catalina.logger.LoggerBase stop怎么回事?? jsp不提交表单,获取下拉菜单的值,并根据值操作? FreeMarker,Velocity有什么用 spring 事务 如何在jsp页面中往request里加东西? struts跳转错误:Path tran.jsp does not start with a "/" character jsp环境配置的问题 关于split sql写法的问题 关于传值问题 请问有那些JSP服务器? 请高手解决这个问题吧,JSP中调用jasper文件 wap开发与misc的接口疑问(简单)
import javax.servlet.*;
import java.util.*;
public class listenerBean implements ServletContextListener {
private java.util.Timer timer = null;
public void contextInitialized(ServletContextEvent event) {
timer = new Timer(true);
//定时器已启动
timer.schedule(new MyTask(), 0, (long) 1000*60);//定时1分钟
//已经添加任务调度表
}
public void contextDestroyed(ServletContextEvent event) {
timer.cancel();
//定时器销毁
}
}
class MyTask extends TimerTask {
private static boolean isRunning = false;
public void run() {
if (!isRunning) {
isRunning = true;
//开始执行任务
//ToDo ....
//执行任务完成
isRunning = false;
} else {
//上一次任务执行还未结束
}
}
}
web.xml <web-app>
<listener>
<listener-class>listenerBean</listener-class>
</listener>
</web-app>
2005-12-15 0:11:30 org.apache.catalina.core.StandardContext listenerStart
严重: Skipped installing application listeners due to previous error(s)
2005-12-15 0:11:30 org.apache.catalina.core.StandardContext start
严重: Error listenerStart
2005-12-15 0:11:30 org.apache.catalina.core.StandardContext start
严重: Context startup failed due to previous errors
2005-12-15 0:11:30 org.apache.catalina.core.StandardHostDeployer install
信息: Processing Context configuration file URL file:C:\Program Files\Apache Software Foundation\Tomcat 5.0\conf\Catalina\localhost\admin.xml
2005-12-15 0:11:31 org.apache.catalina.core.StandardContext listenerStart
严重: Skipped installing application listeners due to previous error(s)
2005-12-15 0:11:31 org.apache.catalina.core.StandardContext start
严重: Error listenerStart
2005-12-15 0:11:31 org.apache.catalina.core.StandardContext start
严重: Context startup failed due to previous errors
2005-12-15 0:11:31 org.apache.catalina.logger.LoggerBase stop
怎么回事??