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自定义分页标签详解
小編覺得挺不錯的,現(xiàn)在分享給大家,幫大家做個參考.
關(guān)于自定義分頁標(biāo)簽的使用，我想大家都見過許多人寫過，我今天也來湊個熱鬧寫下我見到的自定義標(biāo)簽的使用步驟
既然是自定義標(biāo)簽?zāi)敲纯隙ㄉ俨涣祟惡蛅ld文件這兩大因素，因為這兩個才能構(gòu)成標(biāo)簽
首先奉獻(xiàn)上最核心的自定義分頁標(biāo)簽類的寫法PagerTag.java,前提是要繼承自TagSupport類
Java代碼??
<span?style="font-size:?medium;">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;??????public?class?PagerTag?extends?TagSupport?{??????private?static?final?long?serialVersionUID?=?5729832874890369508L;??????private?String?url;?????????????private?int?pageSize?=?10;??????private?int?pageNo?=?1;?????????private?int?recordCount;??????????@SuppressWarnings("unchecked")??????public?int?doStartTag()?throws?JspException?{??????????int?pageCount?=?(recordCount?+?pageSize?-?1)?/?pageSize;????????????????????????????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;#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>沒有可顯示的項目</strong>\r\n");??????????}else{??????????????????????????if(pageNo?>?pageCount){??????pageNo?=?pageCount;?}??????????????if(pageNo?<?1){??????pageNo?=?1;?}????????????????????????????sb.append("<form?method=\"post\"?action=\"").append(this.url)??????????????????.append("\"?name=\"qPagerForm\">\r\n");????????????????????????????????????????HttpServletRequest?request?=?(HttpServletRequest)?pageContext??????????????????????.getRequest();??????????????Enumeration<String>?enumeration?=?request.getParameterNames();??????????????String?name?=?null;??????????????String?value?=?null;?????????????????????????while?(enumeration.hasMoreElements())?{??????????????????name?=??enumeration.nextElement();??????????????????value?=?request.getParameter(name);??????????????????????????????????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");??????????????}????????????????????????????????sb.append("<input?type=\"hidden\"?name=\"").append("pageNo")??????????????????.append("\"?value=\"").append(pageNo).append("\"/>\r\n");????????????????????????????????????????sb.append(" 共<strong>").append(recordCount)??????????????????.append("</strong>項")??????????????????.append(",<strong>")??????????????????.append(pageCount)??????????????????.append("</strong>頁: \r\n");????????????????????????????????????????if?(pageNo?==?1)?{??????????????????sb.append("<span?class=\"disabled\">« 上一頁")??????????????????????.append("</span>\r\n");??????????????}?else?{??????????????????sb.append("<a?href=\"javascript:turnOverPage(")????????????????????.append((pageNo?-?1))????????????????????.append(")\">« 上一頁</a>\r\n");??????????????}????????????????????????????????????????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("…\r\n");??????????????}??????????????????????????int?end?=?this.pageNo?+?1;??????????????if(end?>?pageCount){??????????????????end?=?pageCount;??????????????}??????????????for(int?i?=?start;?i?<=?end;?i++){??????????????????if(pageNo?==?i){???????????????????????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");??????????????????}??????????????}??????????????????????????if(end?<?pageCount?-?2){??????????????????sb.append("…\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");???????????????}????????????????????????????????????????if?(pageNo?==?pageCount)?{??????????????????sb.append("<span?class=\"disabled\">下一頁 »")??????????????????????.append("</span>\r\n");??????????????}?else?{??????????????????sb.append("<a?href=\"javascript:turnOverPage(")??????????????????????.append((pageNo?+?1))??????????????????????.append(")\">下一頁 »</a>\r\n");??????????????}??????????????sb.append("</form>\r\n");????????????????????????????????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");????????????????????????????try?{??????????????pageContext.getOut().println(sb.toString());??????????}?catch?(IOException?e)?{??????????????throw?new?JspException(e);??????????}??????????return?SKIP_BODY;??????}????????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;??????}??}</span>?? ?WEB-INF/pager.tld的寫法
Xml代碼??
<span?style="font-size:?medium;"><?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>?????????<short-name>w</short-name>??????????<uri>http://javacrazyer.iteye.com/tags/pager</uri>????????????????<tag>??????????????????<name>pager</name>??????????????????<tag-class>com.javacrazyer.web.tag.PagerTag</tag-class>??????????????????<body-content>empty</body-content>??????????????????<attribute>??????????????????????????<name>pageNo</name>??????????????????????????<required>true</required>??????????????????????????<rtexprvalue>true</rtexprvalue>??????????????????????????<type>int</type>??????????</attribute>??????????????????<attribute>??????????????<name>recordCount</name>??????????????<required>true</required>??????????????<rtexprvalue>true</rtexprvalue>??????????????<type>int</type>??????????</attribute>??????????????????<attribute>??????????????<name>pageSize</name>??????????????<required>true</required>??????????????<rtexprvalue>true</rtexprvalue>??????????????<type>int</type>??????????</attribute>??????????????????<attribute>??????????????<name>url</name>??????????????<required>true</required>??????????????<rtexprvalue>true</rtexprvalue>??????????????<type>java.lang.String</type>??????????</attribute>??????</tag>??</taglib></span>?? 好了，就上面的兩個基本要素就已經(jīng)構(gòu)成了完整的分頁標(biāo)簽，下面就差在頁面的使用方式了
一般的使用步驟為在JSP頁面中：
先倒入標(biāo)簽庫：<%@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}"/>
具體使用示例，上面兩個類保持不變
這個例子可以說非常好的純servlet項目的例子，大家今后編程如果沒有用到任何框架的話，我希望這個例子能給你帶來點(diǎn)啟示
前提是導(dǎo)入所有需要的jar包：包括common-dbcp.jar(數(shù)據(jù)源需要用到)，common-dbutils-1.2.jar(數(shù)據(jù)庫CURD操作需要用到，可取代最原始的JDBC操作),junit.jar(測試用到)以及數(shù)據(jù)庫驅(qū)動包
關(guān)于上面的common-dbutils非常有用，尤其是在非框架項目中，后面我提供下載
首先數(shù)據(jù)庫，這個數(shù)據(jù)庫腳本是我用navicat導(dǎo)出來的
Sql代碼??
<span?style="font-size:?medium;">/*??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;??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;??</span>?? 實體類News.java
Java代碼??
<span?style="font-size:?medium;">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?+?"]";??????}??????????}</span>?? ?NewsDao.java
Java代碼??
<span?style="font-size:?medium;">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();??????????}</span>?? NewsImplDao.java
Java代碼??
<span?style="font-size:?medium;">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("新增新聞信息時出現(xiàn)異常",?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("分頁查詢出錯",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("刪除新聞信息時出現(xiàn)異常",?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("根據(jù)ID查詢新聞信息時出現(xiàn)異常",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("更新新聞信息出錯",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("查詢記錄總數(shù)出錯",e);??????????}finally{??????????????DbUtils.closeQuietly(conn);??????????}??????????return?count;??????}????}</span>?? ?PageModel.java
Java代碼??
<span?style="font-size:?medium;">package?com.javacrazyer.common;????import?java.util.List;????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;????????}????}??</span>?? ?數(shù)據(jù)庫連接工具類
Java代碼??
<span?style="font-size:?medium;">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;????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();??????}????}</span>?? ? 上面代碼用到的config.properties
Xml代碼??
<span?style="font-size:?medium;">#mysql??driver_name=com.mysql.jdbc.Driver??url=jdbc:mysql:///jstl??username=root??password=root</span>?? DAO實例工具類，類似于Spring的BeanFactory
Java代碼??
<span?style="font-size:?medium;">package?com.javacrazyer.common;????import?java.io.IOException;??import?java.util.Properties;????public?class?DAOFactory?{??????public?static?Properties?pr?=?new?Properties();??????static?{??????????try?{??????????????pr.load(Thread.currentThread().getContextClassLoader()??????????????????????.getResourceAsStream("daoname.properties"));??????????}?catch?(IOException?e)?{??????????????????????????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)?{??????????????????????????????????e.printStackTrace();??????????????}?catch?(IllegalAccessException?e)?{??????????????????????????????????e.printStackTrace();??????????????}?catch?(ClassNotFoundException?e)?{??????????????????????????????????e.printStackTrace();??????????????}??????????}else{??????????????throw?new?RuntimeException("指定名稱的DAO類未找到");??????????}??????????return?obj;??????}??}</span>?? ? 上面代碼用到的配置daoname.properties
Xml代碼??
<span?style="font-size:?medium;">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</span>?? ?平時開發(fā)中常用到的常量存放類
Java代碼??
<span?style="font-size:?medium;">package?com.javacrazyer.common;????import?java.util.LinkedHashMap;??import?java.util.Map;????public?class?Constant?{??????????????????????public?static?final?int?STATUS_ACTIVE?=?1;??????????public?static?final?int?STATUS_INACTIVE?=?0;????????????public?static?final?int?COURSE_FULL_TIME?=?1;??????????public?static?final?int?COURSE_SPARE_TIME?=?2;??????????public?static?final?int?COURSE_FREE_TIME?=?3;????????????public?static?final?int?ACCOUNT_SUPER?=?100;??????????public?static?final?int?ACCOUNT_COMMON?=?50;????????????public?static?final?int?ACCOUNT_STATUS_ACTIVE?=?1;??????????public?static?final?int?ACCOUNT_STATUS_INACTIVE?=?0;??????????public?static?final?int?ACCOUNT_STATUS_LOCK?=?-1;????????????public?static?final?int?PAGE_SIZE?=10;????????private?static?Map<Integer,?String>?statusMap?=?new?LinkedHashMap<Integer,?String>();????????static?{??????????????????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;??????}????}</span>?? 開發(fā)中常用到的用來判斷空值，類型轉(zhuǎn)換，集合操作等等的自定義常用工具類
Java代碼??
<span?style="font-size:?medium;">package?com.javacrazyer.common;????import?java.text.ParseException;??import?java.text.SimpleDateFormat;??import?java.util.Collection;??import?java.util.Date;??import?java.util.Map;????public?class?DataOptUtil?{??????????????????????public?static?final?String?DATE_PATTERN_LONG?=?"yyyy-MM-dd?HH:mm:ss";??????????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("字符串為空，不能轉(zhuǎn)換成數(shù)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("字符串為空，不能轉(zhuǎn)換成日期");??????????}??????????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;??????}??}</span>?? 還有一個自定義非受檢異常類
Java代碼??
<span?style="font-size:?medium;">package?com.javacrazyer.common;????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);??????}????????}??</span>?? 頁面方面
index.html
Java代碼??
<span?style="font-size:?medium;"><html>??????<head>???????????<meta?http-equiv="Content-Type"?content="text/html;?charset=UTF-8"?/>???????????<meta?http-equiv="refresh"?content="0;?url=do.jsp"?/>??????</head>??</html></span>?? do.jsp
Java代碼??
<span?style="font-size:?medium;"><%@?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);??%></span>?? ?index.jsp
Java代碼??
<span?style="font-size:?medium;"><%@?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>新聞列表</h3><hr/>?????<table>?????<tr><td>新聞編號</td><td>新聞標(biāo)題</td><td>新聞內(nèi)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></span>?? ?實際運(yùn)行出來的效果
雖然自定義標(biāo)簽使用成功了，但總不可能每次開發(fā)項目都寫下這個類和加上TLD文件吧，比較簡潔的方式就是將編譯類編譯好的class文件和tld一起打成jar包，以后直接導(dǎo)入到項目lib中就可以使用了
具體步驟：將整個目錄com/javacrazyer/web/tag/PagerTag.class放到一個目錄中去，同時將META-INF拷貝到與com目錄相同的目錄下，最后將WEB-INF下的pager.tld拷貝到MET-INF下
META-INF中的文件
最后將com文件夾與META-INF文件選中右鍵添加到壓縮文件，選中ZIP壓縮格式
改名為jar后綴后確定，這樣在同一目錄就會多出一個jar來了
以后只要在需要的地方導(dǎo)入該分頁JAR包，并且在網(wǎng)頁上
<%@taglib?uri="http://javacrazyer.iteye.com/tags/pager" prefix="w"%>
?<w:pager pageSize="${pageSize}" pageNo="${pageNo}" url="do.jsp"?
- commons-dbutils-1.2.jar?(38.2 KB)
- 下載次數(shù): 217
- JavaCrazyerPager5.0_GA.jar?(4.4 KB)
- 下載次數(shù): 269
- JSTL_Pager.rar?(991.6 KB)
- 描述: 完整分頁標(biāo)簽項目
- 下載次數(shù): 542
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