一>>原始类型与包装类型
先定义两个实体类User和Address
User
package cn.entity;
public class User {
private String name;
private int age;
private Address address;
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
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;
}
}
Address
package cn.entity;
public class Address {
private String country; // 国家
private String city; // 城市
private String street; // 街道
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getStreet() {
return street;
}
public void setStreet(String street) {
this.street = street;
}
}
创建出一个action先创建出两个成员变量 然后在核心方法中实例化成员变量。
package cn.action; import cn.entity.Address;
import cn.entity.User; import com.opensymphony.xwork2.ActionSupport; public class ShowOriginalAndJavaBeanAction extends ActionSupport {
private User user;
private String message;
public String execute(){
setUser(new User());
getUser().setName("jbit");
getUser().setAge(23);
Address address=new Address();
address.setCountry("中国");
address.setCity("北京");
address.setStreet("长安街");
getUser().setAddress(address);
setMessage("展示原始类型和JavaBean");
return SUCCESS;
}
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
}
核心配置：struts.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<package name="default" extends="struts-default">
<action name="showOriginalAndJavaBeanAction" class="cn.action.ShowOriginalAndJavaBeanAction">
<result>result.jsp</result>
</action>
</package>
</struts>
result页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="/struts-tags" prefix="s" %>
<%
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 'result.jsp' starting page</title> </head> <body>
信息：<s:property value="message" default="展示数据" /><br/>
姓名：<s:property value="user.name" /><br/>
年龄：<s:property value="user.age" /><br/>
国家：<s:property value="user.address.country" />
<s:debug></s:debug>
</body>
</html>
property标签用于输出ValueStack中对象属性的值，其中value属性用来指定要输出对象的属性，如果没有value属性，则默认输出ValueStack栈顶的对象，类型为Object；default属性是属性值为空时默认的默认值，类型为String
效果展示：
二>>多值类型请求参数的处理
如果在请求中出现多个值对应同一个请求参数的情况，Struts2会将这样的数据转换为面向集合的数据类型，如集合，数组
1.数组
表单代码
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags" %>
<%
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> </head> <body>
<s:form action="ArraysDataTransfer.action">
<s:textfield name="hobbies" label="爱好："/>
<s:textfield name="hobbies" label="爱好："/>
<s:textfield name="hobbies" label="爱好："/> <s:textfield name="numbers[0]" label="数字："/>
<s:textfield name="numbers[1]" label="数字："/>
<s:textfield name="numbers[2]" label="数字："/>
<s:submit value="提交"/>
</s:form>
</body>
</html>
第一个数组属性是hobbies，接收提交的爱好信息；第二个数组属性是numbers，接收提交的数字，如果数据转移要正常工作，这些属性必须存在ValueStack中。在Action类中公开这些属性
ArraysDataTransferAction
package cn.action;
import com.opensymphony.xwork2.ActionSupport;
public class ArraysDataTransferAction extends ActionSupport {
private String[] hobbies;
private Double[] numbers=new Double[3];
public String execute(){
System.out.println("hobbies的长度是"+hobbies.length);
for(int i=0;i<hobbies.length;i++){
System.out.println("hobbies数组中第"+i+"个元素是："+hobbies[i]);
}
System.out.println("numbers的长度是"+numbers.length);
for(int i=0;i<numbers.length;i++){
System.out.println("numbers数组中第"+i+"个元素是："+numbers[i]);
}
return SUCCESS;
}
public String[] getHobbies() {
return hobbies;
}
public void setHobbies(String[] hobbies) {
this.hobbies = hobbies;
}
public Double[] getNumbers() {
return numbers;
}
public void setNumbers(Double[] numbers) {
this.numbers = numbers;
}
}
struts.xml
<action name="ArraysDataTransfer" class="cn.action.ArraysDataTransferAction">
<result name="success">result2.jsp</result>
</action>
result2.jsp
<body>
请查看控制台的输出
</body>
2.集合
使用List与使用数组几乎相同，仅有不同的是集合类型可以借助泛型实现
表单代码
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags" %>
<%
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> </head> <body>
<s:form action="listDataTransfer">
<s:textfield name="hobbies" label="爱好："/>
<s:textfield name="hobbies" label="爱好："/>
<s:textfield name="hobbies" label="爱好："/> <s:textfield name="numbers[0]" label="数字："/>
<s:textfield name="numbers[1]" label="数字："/>
<s:textfield name="numbers[2]" label="数字："/> <s:textfield name="users.name" label="姓名："/>
<s:textfield name="users.name" label="姓名："/>
<s:textfield name="users.name" label="姓名："/>
<s:submit value="提交"/>
</s:form>
</body>
</html>
相同名称参数有多个数据输入，可以将具有相同名称的参数看作一个集合，特殊说明的是users.name，当ognl解析这个表达式时，会首先定位user属性，与之不同的是，user是一个指定了元素为User对象的List。
ListDataTransferAction
package cn.action;
import com.opensymphony.xwork2.ActionSupport;
import cn.entity.User;
import java.util.*;
public class ListDataTransferAction extends ActionSupport {
private List<String> hobbies;
private List<Double> numbers;
private List<User> users;
public String execute(){
System.out.println("hobbies的长度是"+hobbies.size());
for(int i=0;i<hobbies.size();i++){
System.out.println("hobbies数组中第"+i+"个元素是："+hobbies.get(i));
}
System.out.println("numbers的长度是"+numbers.size());
for(int i=0;i<numbers.size();i++){
System.out.println("numbers数组中第"+i+"个元素是："+numbers.get(i));
}
System.out.println("users的长度是"+users.size());
for(int i=0;i<users.size();i++){
System.out.println("users数组中第"+i+"个元素是："+users.get(i).getName());
}
return SUCCESS;
}
public List<String> getHobbies() {
return hobbies;
}
public void setHobbies(List<String> hobbies) {
this.hobbies = hobbies;
}
public List<Double> getNumbers() {
return numbers;
}
public void setNumbers(List<Double> numbers) {
this.numbers = numbers;
}
public List<User> getUsers() {
return users;
}
public void setUsers(List<User> users) {
this.users = users;
}
}
struts.xml
<action name="listDataTransfer" class="cn.action.ListDataTransferAction">
<result>result2.jsp</result>
</action>
result2.jsp
<body>
请查看控制台的输出
</body>
三>>访问集合对象
package cn.action; import java.util.ArrayList;
import java.util.List; import cn.entity.Address;
import cn.entity.User; import com.opensymphony.xwork2.ActionSupport; public class ShowArraysAndListAction extends ActionSupport { private String[] hobbies;
private List<Double> numbers;
private List<User> users; private User user; public String execute() throws Exception {
users=new ArrayList<User>();
user=new User();
user.setUsername("火狐");
user.setPassword("11");
Address address=new Address();
address.setCountry("中国");
address.setCity("北京");
address.setStreet("长安街");
user.setAddress(address);
users.add(user);
user=new User();
user.setUsername("hh");
user.setPassword("10");
Address address2=new Address();
address2.setCountry("中国");
address2.setCity("北京");
address2.setStreet("海淀");
user.setAddress(address);
users.add(user);
return SUCCESS; } public String[] getHobbies() {
return hobbies;
} public void setHobbies(String[] hobbies) {
this.hobbies = hobbies;
} public List<Double> getNumbers() {
return numbers;
} public void setNumbers(List<Double> numbers) {
this.numbers = numbers;
} public List<User> getUsers() {
return users;
} public void setUsers(List<User> users) {
this.users = users;
} }
实体类
User
package cn.entity;
public class User {
//用户输入的姓名
private String username;
//用户输入的密码
private String password;
private Address address;
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
/*
* 获取名字
* @return 名字
*/
public String getUsername() {
return username;
}
/*
* 设置名字
* @para name名字
*/
public void setUsername(String username) {
this.username = username;
}
/*
* 获取密码
* @return 密码
*/
public String getPassword() {
return password;
}
/*
* 设置密码
* @para password密码
*/
public void setPassword(String password) {
this.password = password;
}
}
Address
package cn.entity;
public class Address {
private String country; // 国家
private String city; // 城市
private String street; // 街道
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getStreet() {
return street;
}
public void setStreet(String street) {
this.street = street;
}
}
struts.xml
<action name="showArrayAndListAction" class="cn.action.ShowArraysAndListAction">
<result name="success">result.jsp</result>
</action>
result.jsp
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>
<%@ taglib uri="/struts-tags" prefix="s"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>"> <title>My JSP 'result.jsp' starting page</title> </head> <body>
迭代数组输出：<br/>
<s:iterator value="hobbies">
<s:property /><br/>
</s:iterator>
迭代集合（元素类型为Double）：<br/> <s:iterator value="numbers">
<s:property /><br/>
</s:iterator> 迭代集合（元素类型为User）：<br/> <s:iterator value="users">
用户名:<s:property value="username" /><br />
密码:<s:property value="password" /><br />
国家:<s:property value="address.country" /><br />
</s:iterator> <s:debug></s:debug>
</body>
</html>
效果: