07820170914jstl自定义标签：主要用于移除Jsp页面中的java代码1、编写一个类，继承SimpleTagSupport[类属性与配置在tld中的属性参数一致，添加set、get方法]2、重写doTage(标签的核心方法，输出标签的内容)3、编写一个tld文件(描述标签的属性[标签名、对应的类、对应的uri...])package com.tiger.tag;import java.io.IOException;import java.util.Map;import java.util.Set;import javax.servlet.jsp.JspException;import javax.servlet.jsp.tagext.SimpleTagSupport;/** * 遍历集合,nobody * @author tiger * @time 2017年9月13日 */public class MySelect extends SimpleTagSupport{	//设置参数,与.tld文件中attribute中的name一致	private Map        map;		private String path;	public String getPath() {		return path;	}	public void setPath(String path) {		this.path = path;	}	public Map          getMap() {		return map;	}	public void setMap(Map            map) {		this.map = map;	}		@Override	public void doTag() throws JspException, IOException  {		//内置一个pageContext对象，它里面是封装了9个隐式对象		StringBuffer htmlBuffer=new StringBuffer();		//遍历集合元素		htmlBuffer.append("      ");		Set set = map.keySet();		for (Object key : set) {			htmlBuffer.append(""); htmlBuffer.append(map.get(key)); htmlBuffer.append(" ");		}		htmlBuffer.append(" ");		getJspContext().getOut().println(htmlBuffer.toString());	}}package com.tiger.tag;import java.io.IOException;import java.util.ArrayList;import java.util.Collection;import java.util.HashMap;import java.util.Iterator;import java.util.Map;import java.util.Set;import javax.servlet.jsp.JspException;import javax.servlet.jsp.JspWriter;import javax.servlet.jsp.tagext.SimpleTagSupport;/** * 遍历集合,hasbody * @author tiger * @time 2017年9月13日 */public class MySelectBody extends SimpleTagSupport{	//设置参数,与.tld文件中attribute中的name一致	private Map              map;	private String path;		public String getPath() {		return path;	}	public void setPath(String path) {		this.path = path;	}	public Map                getMap() { return map; } public void setMap(Map                  map) { this.map = map; } @Override public void doTag() throws JspException, IOException { JspWriter out = getJspContext().getOut(); out.println("         "); Iterator it = map.keySet().iterator(); while (it.hasNext()) { getJspContext().setAttribute("map", map.get(it.next())); getJspBody().invoke(null); } out.println(""); } }                                JSTL 1.1 core library                                JSTL core                                1.1                                tiger                                http://www.tiger.com/tigertag                                                                    table                                               com.tiger.tag.MyTable                                               empty                                                 collection                                                   true                                                   true                                                                                             select                                               com.tiger.tag.MySelect                                               empty                                                 map                                                   true                                                   true                                                              path                                                   true                                                   true                                                                                             selectbody                                               com.tiger.tag.MySelectBody                                               scriptless                                                 map                                                   true                                                   true                                                              path                                                   true                                                   true                                             <%@page import="java.util.HashMap"%> <%@page import="java.util.Map"%> <%@page import="java.util.Collection"%> <%@page import="java.util.Collections"%> <%@page import="java.util.ArrayList"%> <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>           <%@ taglib prefix="my" uri="http://www.tiger.com/tigertag"%> <% Map                    map = new HashMap                     (); map.put("001", "tiger"); map.put("002", "hello"); map.put("003", "xixi"); pageContext.setAttribute("map", map); %>                         <%@page import="java.util.HashMap"%> <%@page import="java.util.Map"%> <%@page import="java.util.Collection"%> <%@page import="java.util.Collections"%> <%@page import="java.util.ArrayList"%> <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>              <%@ taglib prefix="my" uri="http://www.tiger.com/tigertag"%>             ----自定义标签库-hasbody----  <% Map                          map = new HashMap                           (); map.put("001", "body"); map.put("002", "呵呵"); map.put("003", "嘻嘻"); pageContext.setAttribute("map", map); %>                               ${map}