標籤:jsp tag 自訂標籤
作用
在我們開發中,介面和程式碼是分開做的美工做介面但是美工不懂得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訂標籤,到時再jsp中我們只需要加入一段引用標籤代碼就好了不會影響美工工作此外jsp檔案簡單,方便我們以後修改
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;@Overridepublic 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;}@Overridepublic 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頁面加入以下內容
<!--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內加入 --> <cc:myTag username="admin" />
先看我資料庫有條記錄
jsp展示後
結果正確
jsp自定標籤(並且注入spring容器中的bean)