20.struts2的数据填充和类型转换.md

目录
[toc]

1. struts2的自动填充

当jsp和Action类中对象名称一致时候，拦截器会自动拦截填充。
拦截器：

Demo:

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP 'index.jsp' starting page</title>
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
  </head>
  
  <body>
    <form action="${pageContext.request.contextPath}/user_register.action" method="post">
        用户名:<input type="text" name="name"><br/>
        年     龄:<input type="text" name="age"><br/>
        生     日:<input type="text" name="birth"><br/>
        
        <input type="submit" value="注册">
    </form>
  </body>
</html>

package per.liyue.struts2_datafomat;


import java.util.Date;


import com.opensymphony.xwork2.ActionSupport;


public class UserAction extends ActionSupport{
	
	/*
	* 注意：一定要提供Setter方法
	*/
	private String name;
	private int age;
	private Date birth;
	
	public String getName() {
		return name;
	}


	public void setName(String name) {
		this.name = name;
	}


	public int getAge() {
		return age;
	}


	public void setAge(int age) {
		this.age = age;
	}


	public Date getBirth() {
		return birth;
	}


	public void setBirth(Date birth) {
		this.birth = birth;
	}


	public String register(){
		System.out.println(name);
		System.out.println(age);
		System.out.println(birth);
		
		return "register";
	}
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
    <package name="data_conversion"  extends="struts-default" >
        
        <!-- 使用通配符实现 -->        
        <action name="user_*" class="per.liyue.struts2_datafomat.UserAction" method="{1}">
            <result name="{1}">/user.jsp</result>
        </action>
        
    </package>
    
</struts>

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
    
    <!-- 在总配置文件中引入其他配置文件 -->
    <include file="per/liyue/code/struts2demo/config_HelloStruts2.xml"></include>  
    
    <include file="per/liyue/code/struts2_data/data.xml"></include>   
    
    <include file="per/liyue/struts2_datafomat/data_conversion.xml"></include>   
</struts>

在浏览器地址栏输入：

http://localhost.:8080/StrutsDemo1/user_register.action

填写后提交，得到输入内容

2. struts2的对象填充

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP 'index.jsp' starting page</title>
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
  </head>
  
  <body>
    <form action="${pageContext.request.contextPath}/user_register.action" method="post">
        用户名:<input type="text" name="user.name"><br/>
        年     龄:<input type="text" name="user.age"><br/>
        生     日:<input type="text" name="user.birth"><br/>
        
        <input type="submit" value="注册">
    </form>
  </body>
</html>

package per.liyue.struts2_datafomat;
import java.util.Date;
public class User {
    /*
     * 注意：一定要提供Setter方法
     */
    private String name;
    private int age;
    private Date birth;
    
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public Date getBirth() {
        return birth;
    }
    public void setBirth(Date birth) {
        this.birth = birth;
    }
}

package per.liyue.struts2_datafomat;


import java.util.Date;


import com.opensymphony.xwork2.ActionSupport;


public class UserAction extends ActionSupport{
	/*
	* 注意：提供setter和getter方法
	*/
	private User user;	
	public User getUser() {
		return user;
	}


	public void setUser(User user) {
		this.user = user;
	}


	public String register(){
		System.out.println(user.getName());
		System.out.println(user.getAge());
		System.out.println(user.getBirth());
		
		return "register";
	}
}

其他保持不变，浏览器地址栏输入：

http://localhost.:8080/StrutsDemo1/user_register.action

填写后提交，得到输入内容.

3. struts2的类型转换器

对于一些没有按照指定格式输入的内容，那么可以用自定义的类型转换器来处理：

3.1 类继承关系

---TypeConverter
------DefaultTypeConverter
---------StrutsTypeConverter

3.2 局部转换器

步骤：

编写转换器类：继承转换类
在包下建立属性文件,文件名称严格按照格式

Action名称-conversion.properties
然后配置:需要转换的字段名=自定义转换器类的权限名称
例如birthday=cn.itcast.convertor.DateTypeConvertor

3.3 全局转换器

步骤：

继承转换类，实现抽象方法

在包下建立属性文件，严格按照格式

xwork-conversion.properties

3.4 注意

二者可以同时共用，但是同时出现时候优先局部转换器