自定义标签库循环标签

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实现一个循环标签

首先实现一个类

package com.tagtest.test;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;

public class CircleTag extends TagSupport {

int time;

public int getTime() {
return time;
}

public void setTime(int time) {
this.time = time;
}

@Override
public int doStartTag() throws JspException {
return EVAL_BODY_INCLUDE;
}

@Override
public int doEndTag() throws JspException {
return EVAL_PAGE;
}

@Override
public int doAfterBody() throws JspException {

if(time<=1){
return SKIP_BODY;
}else{
time--;
return EVAL_BODY_AGAIN;
}
}

}

在.tld中配置

<?xml version="1.0" encoding="UTF-8" ?>

<taglib xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
version="2.0">
<description>A tag who can caculate time</description>
<tlib-version>1.0</tlib-version>
<short-name>util</short-name>
<uri>http://www.sonppengfei.com/util</uri>
<tag>
<description>caculate time</description>
<name>timer</name>
<tag-class>com.tagtest.test.TimerTag</tag-class>
<body-content>JSP</body-content>
</tag>

<tag>
<description>output time</description>
<name>outtime</name>
<tag-class>com.tagtest.test.DateTag</tag-class>
<body-content>empty</body-content>
<attribute>
<description>who can output time</description>
<name>date</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
</tag>
<tag>
<description>output time</description>
<name>circle</name>
<tag-class>com.tagtest.test.CircleTag</tag-class>
<body-content>JSP</body-content>
<attribute>
<description>circle</description>
<name>time</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
</tag>
</taglib>

在代码中调用

<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="song" uri="http://www.sonppengfei.com/util"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
</head>

<body>
This is my JSP page.
<br>
</body>
<song:circle time ="3">
<song:timer>
<%
for(int i = 0;i<100000000;i++){
}

%>

</song:timer>

<song:outtime date="<%=new Date(1988,10,27)%>" />
</song:circle>
</html>

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自定义标签库 循环标签

自定义标签库循环标签