struts中表单的重复提交和不重复提交

1.工程如图：

2.UserAction.java

package com.ask.action;
 import com.opensymphony.xwork2.ActionSupport;
 public class UserAction extends ActionSupport{
 private String username;
 private String password;
    public String getUsername() {
return username;
 }
 public void setUsername(String username) {
this.username = username;
 }
 public String getPassword() {
return password;
 }public void setPassword(String password) {
this.password = password;
 }

 public String test(){
 System.out.println(username);
 System.out.println(password);
 try {
Thread.sleep(3000);
System.out.println("休眠结束");
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
 return "test";
   }
 }

3.struts.xml

4.index.jsp

5.重复提交效果如下：

6.不可以重复提交效果如下：