struts2封装请求参数

利用struts2框架进行将页面请求的参数封装有三种方法

第一种（不推荐）

就是动作类和bean中结合在一起，这样方法比较简单，但是很混乱。

代码：

package com.example.action;

import com.opensymphony.xwork2.ActionSupport;

public class Person extends ActionSupport{

    private String username;
    private String password;
    private String nickname;
    public String getUsername() {
        return username;
    }

    //动作的方法
    public String execute() throws Exception {
        System.out.println(username+","+password+","+nickname);
        return NONE;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public String getNickname() {
        return nickname;
    }
    public void setNickname(String nickname) {
        this.nickname = nickname;
    }
}

  <action name="act1"  class="com.example.action.Person">
         <!--  静态注入  相当于调用action动作类的get 和set 方法-->

         
          <param name="nickname">游客</param>
</action>

第二种将动作类与bean中分离

package com.example.domain;
/**
 *  这是模型
 * @author sheldonLee
 *
 */
public class Student {

    private String username;
    private String password;
    private String nickname;
    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 getNickname() {
        return nickname;
    }
    public void setNickname(String nickname) {
        this.nickname = nickname;
    }
    @Override
    public String toString() {
        return "Student [username=" + username + ", password=" + password
                + ", nickname=" + nickname + "]";
    }
    
}

package com.example.action;

import com.example.domain.Student;

/**
 * 这是动作
 * @author sheldonLee
 *
 */
public class StudentAction {

    private Student student;

    public Student getStudent() {
        return student;
    }

    public void setStudent(Student student) {
        this.student = student;
    }
    
    public String save(){
        //将表单的数据封装到模型对象中
        //调用service  将student中的数据保存到数据库中
        System.out.println(student.toString());
        return "none";
    }
}

  <body>
   <form action="${pageContext.request.contextPath }/act2" method="post">
   用户名：<input type="text" name="student.username"/><br/>
   密     码：<input type="password" name="student.password"/><br/>
   昵     称: <input type="text" name="student.nickname"/><br/>
   <input  type="submit" value="注册"/><br/>
 </form>

第三种是驱动模型（动作和bean也是分开的）ModelDriven

package com.example.domain;
/**
 *  这是Customer模型
 * @author sheldonLee
 *
 */
public class Customer {
    private String username;
    private String password;
    private String nickname;
    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 getNickname() {
        return nickname;
    }
    public void setNickname(String nickname) {
        this.nickname = nickname;
    }
    @Override
    public String toString() {
        return "Customer [username=" + username + ", password=" + password
                + ", nickname=" + nickname + "]";
    }
    
}

package com.example.action;

import com.example.domain.Customer;
import com.opensymphony.xwork2.ModelDriven;

public class CustomerAction implements ModelDriven<Customer>{

    //动作类关联一个Customer 对象
    //为了getModel() 这个不会返回为空 所以要是实例化一个对象
    private Customer customer= new Customer();

    public Customer getCustomer() {
        return customer;
    }

    public void setCustomer(Customer customer) {
        this.customer = customer;
    }
    
    public String save(){
        System.out.println(customer);
        return "none";
    }
    //调用动作方法前，框架会先调用这个方法
    //这里不会实例化对象
    public Customer getModel() {
        // TODO Auto-generated method stub
        return customer;
    }
}

   <form action="${pageContext.request.contextPath }/act2" method="post">
   <!--参数中省掉了类名 -->
   用户名：<input type="text" name="username"/><br/>
   密     码：<input type="password" name="password"/><br/>
   昵     称: <input type="text" name="nickname"/><br/>
   <input  type="submit" value="注册"/><br/>
 </form>

主要注意两点动作类要实现ModelDriver的接口，动作类中要关联对象要注意要实例化

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原文地址：https://www.cnblogs.com/qerror404/p/4875898.html