自定义标签

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//标签处理程序

package com.sxy008;

import javax.servlet.jsp.JspWriter;

import javax.servlet.jsp.tagext.BodyContent;

import javax.servlet.jsp.tagext.BodyTagSupport;

public class mytag extends BodyTagSupport {

private String name;

public void setName(String name) {

this.name = name;

}

public int doEndTag() {

try {

BodyContent body = this.getBodyContent();//获得主体

String str = body.getString();//获得主体文本内容

JspWriter out =body.getEnclosingWriter();//获得输出对象

out.print(name+str.toUpperCase());//处理

} catch (Exception e) {

System.out.println(e);

}

return 0;

}

<WEB-INF/lib/下创建标签描述文件mytld.tld

<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>JSTL 1.1 core library</description>

<display-name>JSTL core</display-name>

<tlib-version>1.1</tlib-version>

<short-name>xyz</short-name>

<name>mytag</name>

<tag-class>com.sxy008.mytag</tag-class>

<body-content>JSP</body-content>

<description>这是一个变量...</description>

<rtexprvalue>false</rtexprvalue> <!-是否动态获得值,false静态赋值>

<type>java.lang.String</type>

</attribute>

</tag>

<tag>

......

</tag>

</taglib>

自定义标签文件的使用index.jsp

<%@ page language="java" pageEncoding="utf-8"%>

<%@ taglib prefix="my" uri="WEB-INF/lib/mytld.tld" %>

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

<html>

<body>

<my:mytag name="转为大写:">abcdef</my:mytag>

</body>

</html>

空标签处理程序（标签描述文件和上面基本一样，须把 <body-content>里改为empty）

package com.sxy008;

import java.io.IOException;

import javax.servlet.jsp.JspWriter;

import javax.servlet.jsp.tagext.SimpleTagSupport;

public class mytag extends SimpleTagSupport {

private String name;

public void setName(String name) {

this.name = name;

}

public void doTag(){

JspWriter out=this.getJspContext().getOut();

try {

out.print("<font color='red'>"+name+"</font>");

} catch (IOException e) {

e.printStackTrace();

}

使用标签index.jsp