jsp自定标簽（并且注入spring容器中的bean）

作用

在我們開發中，界面和程式代碼是分開做的美工做界面但是美工不懂得Java語言如果我們把Java代碼寫在jsp檔案中，會影響美工工作如果我們使用自定義标簽，到時再jsp中我們隻需要加入一段引用标簽代碼就好了不會影響美工工作此外jsp檔案簡單，友善我們以後修改

1建立類

package com.eyugame.common.tag;

import java.io.IOException;

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

import org.springframework.web.context.ContextLoader;
import org.springframework.web.context.WebApplicationContext;

import com.eyugame.common.service.hibernate.HibernateBaseService;
import com.eyugame.security.entity.SysUser;

public class MyTag extends TagSupport {

	private static HibernateBaseService hibernateBaseService;
	
	private String username;

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	@Override
	public int doStartTag() throws JspException {
		JspWriter writer = this.pageContext.getOut();
		/*擷取bean*/
		if(hibernateBaseService==null){
			WebApplicationContext webApplicationContext = ContextLoader.getCurrentWebApplicationContext();
			hibernateBaseService = (HibernateBaseService) webApplicationContext.getBean("hibernateBaseService");
		}
		/*查詢資料庫*/
		SysUser user = hibernateBaseService.findUniqueByHql(SysUser.class, "from SysUser as u where u.username='" + username + "'");
		try {
			writer.print(user.getNickname());
		} catch (IOException e) {
			e.printStackTrace();
		}
		return SKIP_BODY;
	}

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

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

}
           

建立tld檔案

my.tld

<?xml version="1.0" encoding="UTF-8"?>
<taglib version="2.0" 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 web-jsptaglibrary_2_0.xsd">
	<tlib-version>1.0</tlib-version>
	<jsp-version>2.0</jsp-version>
	<short-name>cc</short-name>
	<uri>/mytaglib</uri>
	<tag>
		<name>myTag</name>
		<tag-class>com.eyugame.common.tag.MyTag</tag-class>
		<body-content>empty</body-content>
		<attribute>
			<name>username</name>
			<required>true</required>
			<rtexprvalue>true</rtexprvalue>
		</attribute>
	</tag>
</taglib>
           

3.web.xml加入以下配置

<jsp-config>
  <taglib>  
    <taglib-uri>/tagTest </taglib-uri>  
    <taglib-location>/tld/my.tld</taglib-location>  
  </taglib>
  </jsp-config>
           

4.jsp頁面加入以下内容

<!--jsp頂部加入， uri是在web項目的上下文路徑 -->
<%@taglib prefix="cc" uri="/tld/my.tld" %>

   <!-- 在body内加入 -->
   <cc:myTag username="admin" />
           

先看我資料庫有條記錄

jsp展示後

結果正确