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                        /JAVA Web开发技术应用——监听器

为什么我每次运行项目时request都initialize了三次

代码如下

```

public class FirstListener implements ServletRequestListener {

// Public constructor is required by servlet spec
public FirstListener() {
}

@Override
public void requestDestroyed(ServletRequestEvent servletRequestEvent) {
System.out.println("request destroyed initParam=" + servletRequestEvent.getServletContext().getAttribute("initParam"));
}

@Override
public void requestInitialized(ServletRequestEvent servletRequestEvent) {
servletRequestEvent.getServletContext().setAttribute("intiParam","yang");
System.out.println("request initialized");
}
}

```

运行结果

```

Connected to server

[2017-12-23 10:44:47,157] Artifact ListenerDemo:war exploded: Artifact is being deployed, please wait...

[2017-12-23 10:44:47,776] Artifact ListenerDemo:war exploded: Artifact is deployed successfully

[2017-12-23 10:44:47,776] Artifact ListenerDemo:war exploded: Deploy took 619 milliseconds

request initialized

request destroyed initParam=null

request initialized

request destroyed initParam=null

request initialized

request destroyed initParam=null

```

qq_何足道_1

2017-12-23

源自：JAVA Web开发技术应用——监听器 3-3

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1 回答

qq_何足道_1 提问者
2017-12-23

额，代码竟然不显示

我再贴一下

public class FirstListener implements ServletRequestListener {

   // Public constructor is required by servlet spec
   public FirstListener() {
   }
@Override
   public void requestDestroyed(ServletRequestEvent servletRequestEvent) {
       System.out.println("request destroyed initParam=" + servletRequestEvent.getServletContext().getAttribute("initParam"));
   }

   @Override
   public void requestInitialized(ServletRequestEvent servletRequestEvent) {
       servletRequestEvent.getServletContext().setAttribute("intiParam","yang");
       System.out.println("request initialized");
   }
}