Java自定义标签库实现及使用示例-优快云博客

本文链接：https://blog.youkuaiyun.com/iteye_18341/article/details/82584218

1.先写java代码
package com.cgm.tldtest;

import java.io.IOException;

import javax.servlet.jsp.JspContext;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.JspFragment;
import javax.servlet.jsp.tagext.JspTag;
import javax.servlet.jsp.tagext.SimpleTag;
//还有一个tag
public class MyTldDate implements SimpleTag {

public void doTag() throws JspException, IOException {
System.out.println("doTag()");

}

public JspTag getParent() {
System.out.println("getParent()");
// TODO Auto-generated method stub
return null;
}

public void setJspBody(JspFragment jspBody) {
System.out.println("setJspBody()");
// TODO Auto-generated method stub

}

public void setJspContext(JspContext pc) {
System.out.println("setJspContext()");
// TODO Auto-generated method stub

}

public void setParent(JspTag parent) {
System.out.println("setParent()");
// TODO Auto-generated method stub

}

}

2.编写tld文件（在web-inf下面tld文件夹写）
<?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">
<tlib-version>1.0</tlib-version>


<short-name>my</short-name>
<uri>http://www.cgmcc.com/jsp/mytag</uri>



<tag>
<name>date</name>

<tag-class>com.cgm.tldtest.MyTldDate</tag-class>


<body-content>empty</body-content>
</tag>

</taglib>

3.jsp 测试

<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%>
<%@ taglib uri="http://www.cgmcc.com/jsp/mytag" prefix="my" %>
<%
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 'mytag.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">


</head>

<body>
<my:date/>

This is my JSP page. <br>
</body>
</html>

运行一下输出。。。。。执行
setJspContext()
doTag()

jstl自定义标签库入门