自定义分页标签详解

关于自定义分页标签的使用，我想大家都见过许多人写过，我今天也来凑个热闹写下我见到的自定义标签的使用步骤

既然是自定义标签那么肯定少不了类和tld文件这两大因素，因为这两个才能构成标签

首先奉献上最核心的自定义分页标签类的写法PagerTag.java,前提是要继承自TagSupport类

package com.javacrazyer.web.tag;

import java.io.IOException;
import java.util.Enumeration;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;


/**
 * 分页标签处理类
 */
public class PagerTag extends TagSupport {
	private static final long serialVersionUID = 5729832874890369508L;
	private String url;         //请求URI
	private int pageSize = 10;  //每页要显示的记录数
	private int pageNo = 1;     //当前页号
	private int recordCount;    //总记录数

	@SuppressWarnings("unchecked")
	public int doStartTag() throws JspException {
		int pageCount = (recordCount + pageSize - 1) / pageSize;  //计算总页数
		
		//拼写要输出到页面的HTML文本
		StringBuilder sb = new StringBuilder();
		
		
		sb.append("<style type=\"text/css\">");
		sb.append(".pagination {padding: 5px;float:right;font-size:12px;}");
		sb.append(".pagination a, .pagination a:link, .pagination a:visited {padding:2px 5px;margin:2px;border:1px solid #aaaadd;text-decoration:none;color:#006699;}");
		sb.append(".pagination a:hover, .pagination a:active {border: 1px solid #ff0000;color: #000;text-decoration: none;}");
		sb.append(".pagination span.current {padding: 2px 5px;margin: 2px;border: 1px solid #ff0000;font-weight: bold;background-color: #ff0000;color: #FFF;}");
		sb.append(".pagination span.disabled {padding: 2px 5px;margin: 2px;border: 1px solid #eee; color: #ddd;}");
		sb.append("</style>\r\n");
		sb.append("<div class=\"pagination\">\r\n");
		if(recordCount == 0){
			sb.append("<strong>没有可显示的项目</strong>\r\n");
		}else{
			//页号越界处理
			if(pageNo > pageCount){		pageNo = pageCount;	}
			if(pageNo < 1){		pageNo = 1;	}
			
			sb.append("<form method=\"post\" action=\"").append(this.url)
				.append("\" name=\"qPagerForm\">\r\n");
			
			//获取请求中的所有参数
			HttpServletRequest request = (HttpServletRequest) pageContext
					.getRequest();
			Enumeration<String> enumeration = request.getParameterNames();
			String name = null;  //参数名
			String value = null; //参数值
			//把请求中的所有参数当作隐藏表单域
			while (enumeration.hasMoreElements()) {
				name =  enumeration.nextElement();
				value = request.getParameter(name);
				// 去除页号
				if (name.equals("pageNo")) {
					if (null != value && !"".equals(value)) {
						pageNo = Integer.parseInt(value);
					}
					continue;
				}
				sb.append("<input type=\"hidden\" name=\"")
				  .append(name)
				  .append("\" value=\"")
				  .append(value)
				  .append("\"/>\r\n");
			}
	
			// 把当前页号设置成请求参数
			sb.append("<input type=\"hidden\" name=\"").append("pageNo")
				.append("\" value=\"").append(pageNo).append("\"/>\r\n");
			
			// 输出统计数据
			sb.append("&nbsp;共<strong>").append(recordCount)
				.append("</strong>项")
				.append(",<strong>")
				.append(pageCount)
				.append("</strong>页:&nbsp;\r\n");
			
			//上一页处理
			if (pageNo == 1) {
				sb.append("<span class=\"disabled\">&laquo;&nbsp;上一页")
					.append("</span>\r\n");
			} else {
				sb.append("<a href=\"javascript:turnOverPage(")
				  .append((pageNo - 1))
				  .append(")\">&laquo;&nbsp;上一页</a>\r\n");
			}
			
			//如果前面页数过多,显示"..."
			int start = 1; 
			if(this.pageNo > 4){
				start = this.pageNo - 1;
				sb.append("<a href=\"javascript:turnOverPage(1)\">1</a>\r\n");
				sb.append("<a href=\"javascript:turnOverPage(2)\">2</a>\r\n");
				sb.append("&hellip;\r\n");
			}
			//显示当前页附近的页
			int end = this.pageNo + 1;
			if(end > pageCount){
				end = pageCount;
			}
			for(int i = start; i <= end; i++){
				if(pageNo == i){   //当前页号不需要超链接
					sb.append("<span class=\"current\">")
						.append(i)
						.append("</span>\r\n");
				}else{
					sb.append("<a href=\"javascript:turnOverPage(")
						.append(i)
						.append(")\">")
						.append(i)
						.append("</a>\r\n");
				}
			}
			//如果后面页数过多,显示"..."
			if(end < pageCount - 2){
				sb.append("&hellip;\r\n");
			}
			if(end < pageCount - 1){
				sb.append("<a href=\"javascript:turnOverPage(")
				.append(pageCount - 1)
				.append(")\">")
				.append(pageCount - 1)
				.append("</a>\r\n");
			}
			if(end < pageCount){
				sb.append("<a href=\"javascript:turnOverPage(")
				.append(pageCount)
				.append(")\">")
				.append(pageCount)
				.append("</a>\r\n"); 
			}
			
			//下一页处理
			if (pageNo == pageCount) {
				sb.append("<span class=\"disabled\">下一页&nbsp;&raquo;")
					.append("</span>\r\n");
			} else {
				sb.append("<a href=\"javascript:turnOverPage(")
					.append((pageNo + 1))
					.append(")\">下一页&nbsp;&raquo;</a>\r\n");
			}
			sb.append("</form>\r\n");
	
			// 生成提交表单的JS
			sb.append("<script language=\"javascript\">\r\n");
			sb.append("  function turnOverPage(no){\r\n");
			sb.append("    if(no>").append(pageCount).append("){");
			sb.append("      no=").append(pageCount).append(";}\r\n");
			sb.append("    if(no<1){no=1;}\r\n");
			sb.append("    document.qPagerForm.pageNo.value=no;\r\n");
			sb.append("    document.qPagerForm.submit();\r\n");
			sb.append("  }\r\n");
			sb.append("</script>\r\n");
		}
		sb.append("</div>\r\n");
		
		//把生成的HTML输出到响应中
		try {
			pageContext.getOut().println(sb.toString());
		} catch (IOException e) {
			throw new JspException(e);
		}
		return SKIP_BODY;  //本标签主体为空,所以直接跳过主体
	}

	public void setUrl(String url) {
		this.url = url;
	}
	public void setPageSize(int pageSize) {
		this.pageSize = pageSize;
	}
	public void setPageNo(int pageNo) {
		this.pageNo = pageNo;
	}
	public void setRecordCount(int recordCount) {
		this.recordCount = recordCount;
	}
}

 WEB-INF/pager.tld的写法

<?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>0.9</tlib-version>
   <!--标签头-->
	<short-name>w</short-name>
    <!--将来在页面用taglib引用时的uri属性,这部分的名字可以随便写，只要是符合HTTP网址形式的	-->
	<uri>http://javacrazyer.iteye.com/tags/pager</uri>
	
	<!-- 自定义标签的描述信息 -->
	<tag>
		<!-- 标签名 -->
		<name>pager</name>
		<!-- 对应的标签处理类全限定名 -->
		<tag-class>com.javacrazyer.web.tag.PagerTag</tag-class>
		<!-- 标签主体的类型 -->
		<body-content>empty</body-content>
		<!-- 当前页号属性的描述信息 -->
		<attribute>
			<!-- 属性名 -->
			<name>pageNo</name>
			<!-- 该属性是否为必要的 -->
			<required>true</required>
			<!-- 属性值是否可以在JSP运行时期动态产生 -->
			<rtexprvalue>true</rtexprvalue>
			<!-- 属性的数据类型 -->
			<type>int</type>
		</attribute>
		<!-- 总记录数属性的描述信息 -->
		<attribute>
			<name>recordCount</name>
			<required>true</required>
			<rtexprvalue>true</rtexprvalue>
			<type>int</type>
		</attribute>
		<!-- 总页数属性的描述信息 -->
		<attribute>
			<name>pageSize</name>
			<required>true</required>
			<rtexprvalue>true</rtexprvalue>
			<type>int</type>
		</attribute>
		<!-- 分页标签要跳转的URI属性的描述信息 -->
		<attribute>
			<name>url</name>
			<required>true</required>
			<rtexprvalue>true</rtexprvalue>
			<type>java.lang.String</type>
		</attribute>
	</tag>
</taglib>

 

好了，就上面的两个基本要素就已经构成了完整的分页标签，下面就差在页面的使用方式了

一般的使用步骤为在JSP页面中：

先倒入标签库：<%@taglib uri="http://javacrazyer.iteye.com/tags/pager" prefix="w"%>

然后使用： <w:pager pageSize="${pageSize}" pageNo="${pageNo}" url="do.jsp" recordCount="${pm.recordCount}"/>

 

具体使用示例，上面两个类保持不变

这个例子可以说非常好的纯servlet项目的例子，大家今后编程如果没有用到任何框架的话，我希望这个例子能给你带来点启示

前提是导入所有需要的jar包：包括common-dbcp.jar(数据源需要用到)，common-dbutils-1.2.jar(数据库CURD操作需要用到，可取代最原始的JDBC操作),junit.jar(测试用到)以及数据库驱动包

关于上面的common-dbutils非常有用，尤其是在非框架项目中，后面我提供下载

 

 

首先数据库，这个数据库脚本是我用navicat导出来的

/*
Navicat MySQL Data Transfer
Source Host     : localhost:3306
Source Database : jstl
Target Host     : localhost:3306
Target Database : jstl
Date: 2010-11-18 14:30:30
*/

SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for news
-- ----------------------------
DROP TABLE IF EXISTS `news`;
CREATE TABLE `news` (
  `detail` varchar(255) DEFAULT NULL,
  `name` varchar(255) DEFAULT NULL,
  `id` int(11) NOT NULL AUTO_INCREMENT,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1253 DEFAULT CHARSET=utf8;

 

实体类News.java

package com.javacrazyer.domain;

public class News {
	private int id;
	private String name;
	private String detail;

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getDetail() {
		return detail;
	}

	public void setDetail(String detail) {
		this.detail = detail;
	}

	@Override
	public String toString() {
		return "News [detail=" + detail + ", id=" + id + ", name=" + name + "]";
	}
	

}

 NewsDao.java

package com.javacrazyer.dao;

import com.javacrazyer.common.PageModel;
import com.javacrazyer.domain.News;

public interface NewsDao {
	PageModel<News> findByPager(int pageNo, int pageSize);

	void createNews(News news);
	
	void update(News news);
	
	void delete(int id);
	
	News findbyId(int id);
	
	int findTotalSize();
	

}

NewsImplDao.java

package com.javacrazyer.daoimpl;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

import org.apache.commons.dbutils.DbUtils;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;

import com.javacrazyer.common.ConnectionFactory;
import com.javacrazyer.common.DAOException;
import com.javacrazyer.common.PageModel;
import com.javacrazyer.dao.NewsDao;
import com.javacrazyer.domain.News;

public class NewsDaoImpl implements NewsDao {
	private QueryRunner qr = new QueryRunner();
	public void createNews(News news) {
		
		Connection conn = null;
		String sql = "insert into news(name,detail) "
				+ " values(?,?)";
		Object[] param = { news.getName(),news.getDetail() };
		try {
			conn = ConnectionFactory.getConn();
			qr.update(conn, sql, param);
		} catch (SQLException e) {
			e.printStackTrace();
			throw new DAOException("新增新闻信息时出现异常", e);
		} finally {
			DbUtils.closeQuietly(conn);
		}

	}

	public PageModel<News> findByPager(int pageNo, int pageSize) {
		PageModel<News> pm=new PageModel<News>();
		Connection conn=null;
		String sql="select *from news limit ?,?";
		Object[] param={(pageNo-1)*pageSize,pageSize};
		List<News> cates=null;
		int count;
		try {
			conn=ConnectionFactory.getConn();
			cates=(List<News>)qr.query(conn, sql, new BeanListHandler(News.class), param);
			pm.setDatas(cates);
			pm.setRecordCount(findTotalSize());
		} catch (SQLException e) {			
			e.printStackTrace();
			throw new DAOException("分页查询出错",e);
		}finally{
			DbUtils.closeQuietly(conn);
		}
		return pm;
	}

	public void delete(int id) {
		Connection conn = null;
		String sql = "delete from news where id=?";
		Object[] param = { id };
		try {
			conn = ConnectionFactory.getConn();
			qr.update(conn, sql, param);
		} catch (SQLException e) {
			e.printStackTrace();
			throw new DAOException("删除新闻信息时出现异常", e);
		} finally {
			DbUtils.closeQuietly(conn);
		}
	}

	public News findbyId(int id) {
		News news=null;
		Connection conn=null;
		String sql="select * from news where id=?";
		Object[] param={id};
		try {
			conn=ConnectionFactory.getConn();
			news=(News)qr.query(conn,sql, new BeanHandler(News.class), param);
		} catch (SQLException e) {
			e.printStackTrace();
			throw new DAOException("根据ID查询新闻信息时出现异常",e);
		}finally{
			DbUtils.closeQuietly(conn);
		}
		return news;
	}

	public void update(News news) {
		Connection conn=null;
		String sql="update news set name=?,detail=? where id=?";
		Object[] param={news.getName(),news.getDetail(),news.getId()};
		try {
			conn=ConnectionFactory.getConn();
			qr.update(conn, sql, param);
			
		} catch (SQLException e) {
			e.printStackTrace();
			throw new DAOException("更新新闻信息出错",e);
		}finally{
			DbUtils.closeQuietly(conn);
		}		
	}

	public int findTotalSize() {
		Connection conn=null;
		String sql="select count(id) from news";
		int count=0;
		try {
			conn=ConnectionFactory.getConn();
			count=((Long)qr.query(conn,sql,new ScalarHandler())).intValue();
			
		} catch (SQLException e) {
			e.printStackTrace();
			throw new DAOException("查询记录总数出错",e);
		}finally{
			DbUtils.closeQuietly(conn);
		}
		return count;
	}

}

 PageModel.java

package com.javacrazyer.common;

import java.util.List;

/** 
 * 分页组件(包含当前页结果数据列表和总记录数) 
 * 注意，它不是持久化实体类 
 *  
 */  
public class PageModel<T> {  
    private int recordCount;  
    private List<T> datas;  
      
      
    public int getRecordCount() {  
        return recordCount;  
    }  
    public void setRecordCount(int recordCount) {  
        this.recordCount = recordCount;  
    }  
    public List<T> getDatas() {  
        return datas;  
    }  
    public void setDatas(List<T> datas) {  
        this.datas = datas;  
    }  
}  

 

 数据库连接工具类

package com.javacrazyer.common;

import java.io.IOException;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

import javax.sql.DataSource;

import org.apache.commons.dbcp.BasicDataSource;

/**
 * 
 * 数据库连接工厂类
 * 
 */
public class ConnectionFactory {
    private static DataSource dss=null;
	static{
		Properties pr=new Properties();
		try {
			pr.load(Thread.currentThread().getContextClassLoader().getResourceAsStream("config.properties"));
		} catch (IOException e) {
			e.printStackTrace();
		}
		BasicDataSource ds=new BasicDataSource();
		ds.setDriverClassName(pr.getProperty("driver_name"));
		ds.setUrl(pr.getProperty("url"));
		ds.setUsername(pr.getProperty("username"));
		ds.setPassword(pr.getProperty("password"));
		dss=ds;
	}
	private ConnectionFactory(){}
	public static Connection getConn() throws SQLException{
		return dss.getConnection();
	}

}

  上面代码用到的config.properties

#mysql
driver_name=com.mysql.jdbc.Driver
url=jdbc:mysql:///jstl
username=root
password=root

DAO实例工具类，类似于Spring的BeanFactory

package com.javacrazyer.common;

import java.io.IOException;
import java.util.Properties;

/**
 * 
 * 
 *  自定义简单工厂
 */
public class DAOFactory {
	public static Properties pr = new Properties();
	static {
		try {
			pr.load(Thread.currentThread().getContextClassLoader()
					.getResourceAsStream("daoname.properties"));
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public static Object newInstance(String name){
	    Object obj=null;
		String daoImplName = pr.getProperty(name);
		if(null!=daoImplName){
			try {
				obj=Class.forName(daoImplName).newInstance();
			} catch (InstantiationException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (IllegalAccessException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (ClassNotFoundException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}else{
			throw new RuntimeException("指定名称的DAO类未找到");
		}
		return obj;
	}
}

  上面代码用到的配置daoname.properties

newsdao=com.javacrazyer.daoimpl.NewsDaoImpl
coursedao=com.javacrazyer.web.tag.CourseDAOImpl
teacherdao=com.javacrazyer.web.tag.TeacherDAOImpl
catedao=com.javacrazyer.web.tag.CategoryDAOImpl
gradao=com.javacrazyer.web.tag.GraduateDAOImpl
accountdao=com.javacrazyer.web.tag.AccountDAOImpl

 平时开发中常用到的常量存放类

package com.javacrazyer.common;

import java.util.LinkedHashMap;
import java.util.Map;

/**
 * 系统常量类
 * 
 * @author tjitcast.com
 */
public class Constant {
	
	
	/** 状态：可用 */
	public static final int STATUS_ACTIVE = 1;
	/** 状态：不可用 */
	public static final int STATUS_INACTIVE = 0;

	/** 课程类型：全日制 */
	public static final int COURSE_FULL_TIME = 1;
	/** 课程类型：业务 */
	public static final int COURSE_SPARE_TIME = 2;
	/** 课程类型：免费 */
	public static final int COURSE_FREE_TIME = 3;

	/** 账号类型：超级管理员 */
	public static final int ACCOUNT_SUPER = 100;
	/** 账号类型：普通管理员 */
	public static final int ACCOUNT_COMMON = 50;

	/** 账号状态：激活 */
	public static final int ACCOUNT_STATUS_ACTIVE = 1;
	/** 账号状态：未激活 */
	public static final int ACCOUNT_STATUS_INACTIVE = 0;
	/** 账号状态：锁定 */
	public static final int ACCOUNT_STATUS_LOCK = -1;

	/** 每页要显示的记录数：10 */
	public static final int PAGE_SIZE =10;

	private static Map<Integer, String> statusMap = new LinkedHashMap<Integer, String>();

	static {
		// 对状态Map进行初始化
		statusMap.put(Integer.valueOf(STATUS_ACTIVE), "可用");
		statusMap.put(Integer.valueOf(STATUS_INACTIVE), "不可用");
	}

	public static Map<Integer, String> getStatusMap() {
		return statusMap;
	}

}

 

开发中常用到的用来判断空值，类型转换，集合操作等等的自定义常用工具类

/**
 *  ClassName: DataValidateUtil.java
 *  created on Jul 10, 2009
 *  Copyrights 2009 www.tjicast.com All rights reserved.
 *  site: http://www.tjitcast.com
 *  email: [e-mail]
 *  phone: [phone]
 */
package com.javacrazyer.common;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Collection;
import java.util.Date;
import java.util.Map;

/**
 * 对一些常用数据进行操作的工具类
 * 
 */
public class DataOptUtil {
	
	
	/** 日期长格式 */
	public static final String DATE_PATTERN_LONG = "yyyy-MM-dd HH:mm:ss";
	/** 日期格式 */
	public static final String DATE_PATTERN = "yyyy-MM-dd";
	
	public static boolean isNotNull(String str){
		if(null != str && !"".equals(str)){
			return true;
		}else{
			return false;
		}
	}
	
	public static int parseInt(String str){
		if(isNotNull(str)){
			return Integer.parseInt(str);
		}else{
			throw new RuntimeException("字符串为空，不能转换成数字");
		}
	}
	
	public static Date parseDate(String str, String pattern){
		SimpleDateFormat sdf = new SimpleDateFormat(pattern);
		Date date = null;
		if(isNotNull(str)){
			try {
				date = sdf.parse(str);
			} catch (ParseException e) {
				e.printStackTrace();
			}
		}else{
			throw new RuntimeException("字符串为空，不能转换成日期");
		}
		return date;
	}
	
	public static Date parseDate(String str){
		return parseDate(str, DataOptUtil.DATE_PATTERN);
	}
	
	public static Date parseLongDate(String str){
		return parseDate(str, DataOptUtil.DATE_PATTERN_LONG);
	}
	
	public static String date2String(Date date, String pattern){
		SimpleDateFormat sdf = new SimpleDateFormat(pattern);
		return sdf.format(date);
	}
	
	public static String Date2String(Date date){
		return date2String(date, DataOptUtil.DATE_PATTERN);
	}
	
	public static String Date2LongString(Date date){
		return date2String(date, DataOptUtil.DATE_PATTERN_LONG);
	}
	
	public static int getSize(Collection<?> coll){
		int size = coll == null ? 0 : coll.size();
		return size;
	}
	
	public static int getSize(Map<?,?> map){
		int size = map == null ? 0 : map.size();
		return size;
	}
	
	public static int getLength(Object[] obj){
		int length = 0;
		length = obj == null ? 0 : obj.length;
		return length;
	}
}

 

还有一个自定义非受检异常类

package com.javacrazyer.common;

/**
 *
 * 自定义的非受检异常
 * 
 */
public class DAOException extends RuntimeException {

	private static final long serialVersionUID = 1047748781772098415L;

	public DAOException() {
		super();
	}

	public DAOException(String message, Throwable cause) {
		super(message, cause);
	}

	public DAOException(String message) {
		super(message);
	}

	public DAOException(Throwable cause) {
		super(cause);
	}
	
}

 

页面方面

index.html

<html>
	<head>
		 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> 
		<meta http-equiv="refresh" content="0; url=do.jsp" />
	</head>
</html>

 

do.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@page import="com.javacrazyer.common.DAOFactory"%>
<%@page import="com.javacrazyer.dao.NewsDao"%>
<%@page import="com.javacrazyer.common.PageModel"%>
<%@page import="com.javacrazyer.common.DataOptUtil"%>
<%@page import="com.javacrazyer.common.Constant"%>
<%@page import="com.javacrazyer.domain.News"%>
<%
NewsDao dao=(NewsDao)DAOFactory.newInstance("newsdao");

int pageNo = 1;
String temp = request.getParameter("pageNo");
if (DataOptUtil.isNotNull(temp)) {
	pageNo = Integer.parseInt(temp);
}
int categoryid = 1;
String temp1 = request.getParameter("category_id");
if (DataOptUtil.isNotNull(temp1)) {
	categoryid = Integer.parseInt(temp1);
}
PageModel<News> pm=dao.findByPager(pageNo,Constant.PAGE_SIZE);
request.setAttribute("pm",pm);
request.setAttribute("pageNo", Integer.valueOf(pageNo));
request.setAttribute("pageSize", Constant.PAGE_SIZE);
request.getRequestDispatcher("/index.jsp").forward(request,response);
%>

 index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://javacrazyer.iteye.com/tags/pager" prefix="w"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%
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 'index.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">
	<!--
	<link rel="stylesheet" type="text/css" href="styles.css">
	-->
  </head>
  
  <body>
   <h3>新闻列表</h3><hr/>
   <table>
   <tr><td>新闻编号</td><td>新闻标题</td><td>新闻内容</td></tr> 
   <c:forEach items="${pm.datas}" var="news">
   <tr><td>${news.id}</td><td>${news.name }</td><td>${news.detail}</td></tr>
   </c:forEach>
   </table>
   <w:pager pageSize="${pageSize}" pageNo="${pageNo}" url="do.jsp" recordCount="${pm.recordCount}"/>
  </body>
</html>

 实际运行出来的效果

虽然自定义标签使用成功了，但总不可能每次开发项目都写下这个类和加上TLD文件吧，比较简洁的方式就是将编译类编译好的class文件和tld一起打成jar包，以后直接导入到项目lib中就可以使用了

 

具体步骤：将整个目录com/javacrazyer/web/tag/PagerTag.class放到一个目录中去，同时将META-INF拷贝到与com目录相同的目录下，最后将WEB-INF下的pager.tld拷贝到MET-INF下

META-INF中的文件
 

最后将com文件夹与META-INF文件选中右键添加到压缩文件，选中ZIP压缩格式

改名为jar后缀后确定，这样在同一目录就会多出一个jar来了

 

 

以后只要在需要的地方导入该分页JAR包，并且在网页上

<%@taglib uri="http://javacrazyer.iteye.com/tags/pager" prefix="w"%>

 <w:pager pageSize="${pageSize}" pageNo="${pageNo}" url="do.jsp"

 

 

 

 

 

 

评论

5 楼 sub12050223 2016-03-18  

4 楼 q280499693 2015-01-21  

主要这边少的jar包是，jstl.jar ,jsp-api.jar,commons-pool.jar如果有兴趣的朋友可以找到对应的jar包跑起来看看吧。

3 楼 q280499693 2015-01-21  

楼主，myeclipse项目，用eclipse跑起来各种缺jar包，还要我一个一个找。。。。。。不过总体来说还行，就是不知道以后能不能用上，如果有需要的朋友可以找我要吧，jar包什么我这都有，或者看看楼主能不能整理后再发一下。下边我是准备把这个tag移植到别的项目试试，嘿嘿！

2 楼 lbylbl23 2013-02-20  

少了一个dbcp.jar

1 楼 lbylbl23 2013-02-19  

试了，报错啊
org.apache.jasper.JasperException: An exception occurred processing JSP page /do.jsp at line 21

18: if (DataOptUtil.isNotNull(temp1)) {
19: categoryid = Integer.parseInt(temp1);
20: }
21: PageModel<News> pm=dao.findByPager(pageNo,Constant.PAGE_SIZE);
22: request.setAttribute("pm",pm);
23: request.setAttribute("pageNo", Integer.valueOf(pageNo));
24: request.setAttribute("pageSize", Constant.PAGE_SIZE);


Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:519)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:410)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)