一、struts2标签简介；
struts标签很多，功能强大，这是优点；
但是缺点的话，性能方面可能会，各方面速度啊啥的会降低；有人比较测试，struts性能比jstl低很多；
二、struts2数据标签：
com.cy.model.Student.java:
package com.cy.model;
public class Student {
private int id;
private String name;
private int age;
public Student() {
super();
// TODO Auto-generated constructor stub
}
public Student(int id, String name, int age) {
super();
this.id = id;
this.name = name;
this.age = age;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
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;
}
}
dataTag.jsp:
<body>
<h>数据标签</h>
<hr/>
<a href="data/property.jsp" target="_blank">property标签</a><br/>
<a href="data/set.jsp" target="_blank">set标签</a><br/>
<a href="data/bean.jsp" target="_blank">bean标签</a><br/>
<a href="data/date.jsp" target="_blank">date标签</a><br/>
<a href="data/debug.jsp" target="_blank">debug标签</a><br/>
<a href="data/url_a.jsp" target="_blank">url_a标签</a><br/>
<a href="data/include.jsp" target="_blank">include标签</a><br/>
</body>
property.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
request.setAttribute("name","<font color=red>张三</font>");
%>
</head>
<body>
<s:property value="#request.name" /><br/>
<s:property value="#request.name2" default="某某人"/><br/>
<s:property value="#request.name" default="某某人" escapeHtml="false"/><br/>
</body>
</html>
set.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<s:set var="i" value="1"></s:set>
<s:property value="#i" /><br/>
<s:set var="a" value="'action范围的值'" scope="action"></s:set>
<s:set var="p" value="'page范围的值'" scope="page"></s:set>
<s:set var="r" value="'request范围的值'" scope="request"></s:set>
<s:set var="s" value="'session范围的值'" scope="session"></s:set>
<s:set var="app" value="'application范围的值'" scope="application"></s:set>
<s:property value="#a" /><br/><!-- action范围相当于值栈里面 -->
<s:property value="#attr.p"/><br/>
<s:property value="#request.r"/><br/>
<s:property value="#session.s"/><br/>
<s:property value="#application.app"/><br/>
</body>
</html>
bean.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<s:bean name="com.cy.model.Student" var="student">
<s:param name="name" value="'张三'"></s:param>
<s:param name="age" value="10"></s:param>
</s:bean>
<s:property value="#student.name"/>
<s:property value="#student.age"/>
</body>
</html>
data.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="java.util.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
request.setAttribute("date",new Date());
%>
</head>
<body>
${date }<br/>
<!-- 这种格式化时间的jstl也是有的 -->
当前日期：<s:date name="#request.date" format="yyyy-MM-dd"/><br>
当前日期：<s:date name="#request.date" format="yyyy/MM/dd"/>
</body>
</html>
debug.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<!-- 相当于值栈debug 可以看到valueStack中的值
可以看到attr，request，session，application等...中的值
-->
<s:debug></s:debug>
</body>
</html>
url_a.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<!-- s:url相当于定义一个url变量 -->
<s:url action="hello" namespace="/foreground" id="h">
<s:param name="name" value="'struts2'"></s:param>
</s:url>
<s:a href="%{h}">超链接</s:a> <!-- 相当于上面的写法 -->
<s:a action="hello" namespace="/foreground">
<s:param name="name" value="'struts2'"></s:param>
超链接2
</s:a>
</body>
</html>
include.jsp:和head.html:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<!-- 相当于jsp:include -->
<s:include value="head.html"></s:include>
</body>
</html>
<body>
头部
</body>
测试结果：
property标签结果：
set标签结果：
bean标签结果：
date标签结果：
debug标签结果：
url_a标签结果：
include标签结果：
三、struts2控制标签：
merge标签和append标签是有区别的;
可以看结果显示出来的区别；
append是将list1和list2合并到一起；
merge是组合，有点像取list1中的一个元素，再取list2中的一个元素，....最后将这两个list中的元素合并到一个list里面；
subset：count="2" start="2" 索引从2开始，取两条数据；
com.cy.comparator.MyComparator.java:
package com.cy.comparator;
import java.util.Comparator;
import com.cy.model.Student;
public class MyComparator implements Comparator<Student>{
public int compare(Student s1, Student s2) {
if(s1.getAge()>s2.getAge()){
return 1;
}else if(s1.getAge()<s2.getAge()){
return -1;
}
return 0;
}
}
controlTag.jsp：
<body>
<h>控制标签</h>
<hr/>
<a href="control/ifelse.jsp" target="_blank">ifelse标签</a><br/>
<a href="control/iterator.jsp" target="_blank">iterator标签</a><br/>
<a href="control/append.jsp" target="_blank">append标签</a><br/>
<a href="control/generator.jsp" target="_blank">generator标签</a><br/>
<a href="control/merge.jsp" target="_blank">merge标签</a><br/>
<a href="control/sort.jsp" target="_blank">sort标签</a><br/>
<a href="control/subset.jsp" target="_blank">subset标签</a><br/>
</body>
ifelse.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
int age=11;
request.setAttribute("age",age);
%>
</head>
<body>
<s:if test="#request.age<20">
年龄小于20岁
</s:if>
<s:elseif test="#request.age==20">
年龄等于20岁
</s:elseif>
<s:else>
年龄大于20岁
</s:else>
</body>
</html>
iterator.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="com.cy.model.Student" %>
<%@ page import="java.util.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
List<Student> studentList=new ArrayList<Student>();
studentList.add(new Student(1,"张三",10));
studentList.add(new Student(3,"李四",20));
studentList.add(new Student(5,"王五",30));
request.setAttribute("studentList",studentList);
%>
</head>
<body>
<table>
<tr>
<th>序号</th>
<th>编号</th>
<th>姓名</th>
<th>年龄</th>
</tr>
<s:iterator value="#request.studentList" status="status">
<tr>
<td><s:property value="#status.index+1"/></td>
<td><s:property value="id"/></td>
<td><s:property value="name"/></td>
<td><s:property value="age"/></td>
</tr>
</s:iterator>
</table>
</body>
</html>
append.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="com.cy.model.Student" %>
<%@ page import="java.util.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
List<Student> studentList1=new ArrayList<Student>();
List<Student> studentList2=new ArrayList<Student>();
studentList1.add(new Student(1,"张三",10));
studentList1.add(new Student(3,"李四",20));
studentList2.add(new Student(5,"王五",30));
studentList2.add(new Student(7,"赵六",40));
request.setAttribute("studentList1",studentList1);
request.setAttribute("studentList2",studentList2);
%>
</head>
<body>
<s:append var="studentList3">
<s:param value="#request.studentList1"></s:param>
<s:param value="#request.studentList2"></s:param>
</s:append>
<table>
<tr>
<th>序号</th>
<th>编号</th>
<th>姓名</th>
<th>年龄</th>
</tr>
<s:iterator value="studentList3" status="status">
<tr>
<td><s:property value="#status.index+1"/></td>
<td><s:property value="id"/></td>
<td><s:property value="name"/></td>
<td><s:property value="age"/></td>
</tr>
</s:iterator>
</table>
</body>
</html>
generator.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<s:generator separator="," val="'张三,李四,王五'" var="nameList"></s:generator> <s:iterator value="#nameList">
<s:property/>
</s:iterator>
</body>
</html>
merge.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="com.cy.model.Student" %>
<%@ page import="java.util.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
List<Student> studentList1=new ArrayList<Student>();
List<Student> studentList2=new ArrayList<Student>();
studentList1.add(new Student(1,"张三",10));
studentList1.add(new Student(3,"李四",20));
studentList2.add(new Student(5,"王五",30));
studentList2.add(new Student(7,"赵六",40));
request.setAttribute("studentList1",studentList1);
request.setAttribute("studentList2",studentList2);
%>
</head>
<body>
<s:merge var="studentList3">
<s:param value="#request.studentList1"></s:param>
<s:param value="#request.studentList2"></s:param>
</s:merge>
<table>
<tr>
<th>序号</th>
<th>编号</th>
<th>姓名</th>
<th>年龄</th>
</tr>
<s:iterator value="studentList3" status="status">
<tr>
<td><s:property value="#status.index+1"/></td>
<td><s:property value="id"/></td>
<td><s:property value="name"/></td>
<td><s:property value="age"/></td>
</tr>
</s:iterator>
</table>
</body>
</html>
sort.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="com.cy.model.Student" %>
<%@ page import="java.util.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
List<Student> studentList1=new ArrayList<Student>();
studentList1.add(new Student(1,"张三",20));
studentList1.add(new Student(3,"李四",10));
studentList1.add(new Student(5,"王五",40));
studentList1.add(new Student(7,"赵六",30));
request.setAttribute("studentList1",studentList1);
%>
</head>
<body>
<s:bean id="myComparator" name="com.cy.comparator.MyComparator"></s:bean> <table>
<tr>
<th>序号</th>
<th>编号</th>
<th>姓名</th>
<th>年龄</th>
</tr>
<s:sort comparator="#myComparator" source="#request.studentList1" >
<s:iterator status="status">
<tr>
<td><s:property value="#status.index+1"/></td>
<td><s:property value="id"/></td>
<td><s:property value="name"/></td>
<td><s:property value="age"/></td>
</tr>
</s:iterator>
</s:sort>
</table>
</body>
</html>
subset.jsp:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="com.cy.model.Student" %>
<%@ page import="java.util.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
List<Student> studentList1=new ArrayList<Student>();
studentList1.add(new Student(1,"张三",20));
studentList1.add(new Student(3,"李四",10));
studentList1.add(new Student(5,"王五",40));
studentList1.add(new Student(7,"赵六",30));
request.setAttribute("studentList1",studentList1);
%>
</head>
<body> <table>
<tr>
<th>序号</th>
<th>编号</th>
<th>姓名</th>
<th>年龄</th>
</tr>
<s:subset source="#request.studentList1" count="2" start="2">
<s:iterator status="status">
<tr>
<td><s:property value="#status.index+1"/></td>
<td><s:property value="id"/></td>
<td><s:property value="name"/></td>
<td><s:property value="age"/></td>
</tr>
</s:iterator>
</s:subset>
</table>
</body>
</html>
--------------