使用Struts2的iterator标签遍历复杂Map种类

1.建一个Webproject。加入Struts2支持。

2.创建两个实体类：
a). Mother(母亲)的Java类。

package struts.map.entity;

import java.io.Serializable;

public class Mother implements Serializable {

private static final long serialVersionUID = 1L;

private int motherId;        //母亲ID
    private String motherName;        //母亲名字
    public int getMotherId() {
return motherId;
}
public void setMotherId(int motherId) {
this.motherId = motherId;
}
public String getMotherName() {
return motherName;
}
public void setMotherName(String motherName) {
this.motherName = motherName;
}
}

b).Children(孩子)的Java类

package struts.map.entity;

import java.io.Serializable;

public class Children implements Serializable {

private static final long serialVersionUID = 1L;

private int childId;        //孩子ID
    private int motherId;        //母亲的ID
    private String childName;        //孩子名字

public int getChildId() {
return childId;
}
public void setChildId(int childId) {
this.childId = childId;
}
public int getMotherId() {
return motherId;
}
public void setMotherId(int motherId) {
this.motherId = motherId;
}
public String getChildName() {
return childName;
}
public void setChildName(String childName) {
this.childName = childName;
}
}

3. 创建一个Action。并创建一位母亲和她的孩子。

package struts.map.test;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import struts.map.entity.Children;
import struts.map.entity.Mother;

import com.opensymphony.xwork2.ActionSupport;

public class Struts2_Map extends ActionSupport {

private static final long serialVersionUID = 1L;

private Map<Mother,List<Children>> motherChildn;

public Map<Mother, List<Children>> getMotherChildn() {
return motherChildn;
}

@Override
public String execute() throws Exception {
/*-------------------以对象做父节点的键，List做子节点的值。的Map-----------------------*/
Mother mother = new Mother();
mother.setMotherId(10000);
mother.setMotherName("花木兰");

Children children1 = new Children();
children1.setChildId(10000);
children1.setMotherId(10000);
children1.setChildName("小花木兰1");

Children children2 = new Children();
children2.setChildId(10001);
children2.setMotherId(10000);
children2.setChildName("小花木兰2");

Children children3 = new Children();
children3.setChildId(10002);
children3.setMotherId(10000);
children3.setChildName("小花木兰3");

motherChildn = new HashMap<Mother,List<Children>>();

List<Children> childrens = new ArrayList<Children>();

childrens.add(children1);
childrens.add(children2);
childrens.add(children3);

motherChildn.put(mother,childrens);

return SUCCESS;
}
}

struts.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
<struts>
<package name="map" extends="struts-default">
<action name="struts_map" class="struts.map.test.Struts2_Map">
<result>result.jsp</result>
</action>
</package>
</struts>

4.创建两个页面：
a).跳转页面：

<%@ page language="java" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>

<title>Struts_Map</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">
</head>

<body>
<a href="struts_map.action">查看Map</a>
</body>
</html>

b).终于页面，也是作重要的页面：

<%@ page language="java" pageEncoding="UTF-8"%>
<%@taglib uri="/struts-tags" prefix="s" %>
<%
String path = request.getContextPath();
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>

<title>Struts_Map</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">
</head>

<body>
<div>
<h3>-----------------以对象做父节点的键，List做子节点的值。的Map--------------------</h3>
<s:iterator var="mc" value="motherChildn">
<div>
母亲名称：<s:property value="key.motherName"/>
</div>
<s:iterator var="ch" value="value">
<div>
   孩子名称：<s:property value="#ch.childName"/>
</div>
</s:iterator>
</s:iterator>
</div>
</body>
</html>

终于执行结果：

原文地址：https://www.cnblogs.com/gcczhongduan/p/4668211.html