SSH2简单实现分页效果

 

1、首先数据库部分：字段类型全字符串

2、部署spring、hibernate、struts2、导包建path，新建包，生成pojo及映射文件，目录如下

3、在tools包下编写分页工具bean类

package com.tools;

public class Paging {
	private int pageNow;//当前页
	private int pageSize;//每页显示数
	private int totalRecords;//总记录数
	private int totalPages;//总页数
	
	private boolean hasFirst;//是否有首页
	private boolean hasLast;//是否有尾页
	private boolean hasPre;//是否有前一页
	private boolean hasNext;//是否有后一页
	
	public Paging(){}
	
	public Paging(int pageNow,int pageSize,int totalRecords){
		this.pageNow=pageNow;
		this.pageSize=pageSize;
		this.totalRecords=totalRecords;	//构造器为变量赋值
	}
	
	public int getPageNow() {
		return pageNow;
	}
	public void setPageNow(int pageNow) {
		this.pageNow = pageNow;
	}
	public int getPageSize() {
		return pageSize;	
	}
	public void setPageSize(int pageSize) {
		this.pageSize = pageSize;
	}
	public int getTotalRecords() {
		return totalRecords;
	}
	public void setTotalRecords(int totalRecords) {
		this.totalRecords = totalRecords;
	}
	public int getTotalPages() {
		if(totalRecords%pageSize!=0)
			return totalRecords/pageSize+1;
		else
			return totalRecords/pageSize;
		//return (pageSize+totalRecords-1)/pageSize;//总页数计算
	}
	public void setTotalPages(int totalPages) {
		this.totalPages = totalPages;
	}
	public boolean isHasFirst() {
		if(pageNow==1)			//如果当前页是1，则没有首页
			return false;
		else
			return true;
	}
	public void setHasFirst(boolean hasFirst) {
		this.hasFirst = hasFirst;
	}
	public boolean isHasLast() {
		if(pageNow==this.getTotalPages())	//如果当前页是总页数，则没有尾页
			return false;
		else
			return true;
	}
	public void setHasLast(boolean hasLast) {
		this.hasLast = hasLast;
	}
	public boolean isHasPre() {
		if(pageNow==1)			//如果当前页是1，则没有前一页
			return false;
		else
			return true;
	}
	public void setHasPre(boolean hasPre) {
		this.hasPre = hasPre;
	}
	public boolean isHasNext() {
		if(pageNow==this.getTotalPages())	//如果当前页是总页数，则没有后一页
			return false;
		else
			return true;
	}
	public void setHasNext(boolean hasNext) {
		this.hasNext = hasNext;
	}

	@Override
	public String toString() {
		return "Paging [pageNow=" + pageNow + ", pageSize=" + pageSize + ", totalRecords=" + totalRecords
				+ ", totalPages=" + totalPages + ", hasFirst=" + hasFirst + ", hasLast=" + hasLast + ", hasPre="
				+ hasPre + ", hasNext=" + hasNext + "]";
	}
}

4、在service包下编写业务方法

package com.service;

import java.util.List;

import com.model.Studentsinfo;

public interface InterPagingService {

	public int findTotalRecords();	//查找总记录条数业务方法
	
	public List<Studentsinfo> findShowRecords(int pageNow,int pageSize);	//查找需要显示的记录业务方法
}

package com.service;

import java.util.List;

import com.dao.InterPagingDao;
import com.model.Studentsinfo;

public class PagingServiceImpl implements InterPagingService {

	private InterPagingDao pagingDaoImpl;
	
	public InterPagingDao getPagingDaoImpl() {
		return pagingDaoImpl;
	}
	public void setPagingDaoImpl(InterPagingDao pagingDaoImpl) {
		this.pagingDaoImpl = pagingDaoImpl;
	}
	
	@Override
	public int findTotalRecords() {		
		return pagingDaoImpl.findTotalRecordsDao();
	}
	
	public List<Studentsinfo> findShowRecords(int pageNow,int pageSize){
		int skipRecords=(pageNow-1)*pageSize;	//数据库查询跳过的记录数
		return pagingDaoImpl.findShowRecordsDao(skipRecords,pageSize);
	}

}

5、dao包下编写数据库的操作

package com.dao;

import org.hibernate.Session;
import org.hibernate.SessionFactory;

public class BaseDao {
	
	private SessionFactory sessionFactory;
	private Session session;
	
	public SessionFactory getSessionFactory() {
		return sessionFactory;
	}
	public void setSessionFactory(SessionFactory sessionFactory) {
		this.sessionFactory = sessionFactory;
	}
	public Session getSession(){
		return sessionFactory.openSession();
	}
}

package com.dao;

import java.util.List;

import com.model.Studentsinfo;

public interface InterPagingDao {
	
	public int findTotalRecordsDao();
	
	public List<Studentsinfo> findShowRecordsDao(int skipRecords,int pageSize);
}

package com.dao;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import com.model.Studentsinfo;

public class PagingDaoImpl extends BaseDao implements InterPagingDao {

	@Override
	public int findTotalRecordsDao() {
		
		try{
			Session session=getSession();	//继承中获取session
			Transaction ts=session.beginTransaction();//开始事务
			return session.createQuery("from Studentsinfo").list().size();//返回记录条数
		}catch(Exception e){
			e.printStackTrace();
			return 0;
		}
	}

	@Override
	public List<Studentsinfo> findShowRecordsDao(int skipRecords, int pageSize) {
		
		Session session=getSession();
		Transaction ts=session.beginTransaction();
		Query query=session.createQuery("from Studentsinfo");
		query.setFirstResult(skipRecords);//指定从哪一条记录开始查
		query.setMaxResults(pageSize);	 //设置要查找的记录数
		List<Studentsinfo> list=query.list();
		ts.commit();
		session.close();
		return list;
	}

}

7、在action包下编写流程控制的action类

package com.action;

import java.util.List;
import java.util.Map;

import com.model.Studentsinfo;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.service.InterPagingService;
import com.tools.Paging;

public class PagingAction extends ActionSupport{
	
	private int pageNow=1;	//初始化为当前页为1，通过请求可更改
	private int pageSize=4; //每页显示数为4，同上
	
	private InterPagingService pagingServiceImpl;
	
	public String execute()throws Exception{
		
		pageNow=getPageNow();	//获取要设置的当前页值
		pageSize=getPageSize(); //获取要设置的每页记录数
		int totalRecords=pagingServiceImpl.findTotalRecords();//获取查找到的总记录数
		
		//判断用户可能输入的当前页是否超出范围,超出重置为1
		if(pageNow<1 || pageNow>((pageSize+totalRecords-1)/pageSize))
			pageNow=1;
		
		Map request=(Map)ActionContext.getContext().get("request");
		Paging paging=new Paging(pageNow,pageSize,totalRecords);//获取分页对象

		List<Studentsinfo> list=pagingServiceImpl.findShowRecords(pageNow, pageSize);
		//System.out.println(list);
		//System.out.println(paging);
		request.put("list",list);
		request.put("paging", paging);
		return SUCCESS;
	}
	
	public InterPagingService getPagingServiceImpl() {
		return pagingServiceImpl;
	}

	public void setPagingServiceImpl(InterPagingService pagingServiceImpl) {
		this.pagingServiceImpl = pagingServiceImpl;
	}

	public int getPageNow() {
		return pageNow;
	}

	public void setPageNow(int pageNow) {
		this.pageNow = pageNow;
	}

	public int getPageSize() {
		return pageSize;
	}

	public void setPageSize(int pageSize) {
		this.pageSize = pageSize;
	}

}

6、配置文件web.xml、struts.xml、applicationContext.ml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
  
  <filter>
  	<filter-name>struts2</filter-name>
  	<filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
  </filter>
  <filter-mapping>
  	<filter-name>struts2</filter-name>
  	<url-pattern>/*</url-pattern>
  </filter-mapping>
  
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/classes/applicationContext.xml</param-value>
  </context-param>
</web-app>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
        "http://struts.apache.org/dtds/struts-2.0.dtd">
	<struts>
		<package name="default" extends="struts-default">
		
			<!-- 分页action -->
			<action name="paging" class="pagingAction">
				<result name="success">/paging.jsp</result>
			</action>
			
		</package>
		<!-- <constant name="struts.i18n.encoding" value="gb2312"></constant> -->
	</struts>
 

<?xml version="1.0" encoding="UTF-8"?>
<beans
	xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:p="http://www.springframework.org/schema/p"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd" xmlns:tx="http://www.springframework.org/schema/tx">


	<bean id="dataSource"
		class="org.apache.commons.dbcp.BasicDataSource">
		<property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
		<property name="url" value="jdbc:mysql://localhost:3306/"></property>
		<property name="username" value="root"></property>
		<property name="password" value="root123"></property>
	</bean>
	<bean id="sessionFactory"
		class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
		<property name="dataSource">
			<ref bean="dataSource" />
		</property>
		<property name="hibernateProperties">
			<props>
				<prop key="hibernate.dialect">
					org.hibernate.dialect.MySQLDialect
				</prop>
			</props>
		</property>
		<property name="mappingResources">
			<list>
				<value>com/model/Studentsinfo.hbm.xml</value></list>
		</property></bean>
	<bean id="transactionManager"
		class="org.springframework.orm.hibernate4.HibernateTransactionManager">
		<property name="sessionFactory" ref="sessionFactory" />
	</bean>
	<tx:annotation-driven transaction-manager="transactionManager" />
	
	<bean id="baseDao" class="com.dao.BaseDao">
		<property name="sessionFactory"><ref bean="sessionFactory"></ref></property>
	</bean>
	<bean id="pagingDaoImpl" class="com.dao.PagingDaoImpl" parent="baseDao"></bean>
	<bean id="pagingServiceImpl" class="com.service.PagingServiceImpl">
		<property name="pagingDaoImpl" ref="pagingDaoImpl"></property>
	</bean>
	<bean id="pagingAction" class="com.action.PagingAction">
		<property name="pagingServiceImpl" ref="pagingServiceImpl"></property>
	</bean>
	<bean id="paging" class="com.tools.Paging"></bean>
	
	
	</beans>

7、编写jsp页面输出

<%@ page language="java" import="java.util.*,com.tools.Paging" pageEncoding="utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>   
    <title>ssh2 paging</title>
  </head>
  <script src=js/jquery-3.0.0.min.js></script>

 	<script type="text/javascript">
			
			function pageSizeChange(){			
				var v_pageSize=$("#pageSizeButt").val()			
				document.location.href="paging.action?pageSize="+v_pageSize+"&pageNow=1";
			}
			
			$(function(){
				<%
				Paging pageInfo=(Paging)request.getAttribute("paging");
				int vPageSize=3;
				if(pageInfo!=null)
					vPageSize=pageInfo.getPageSize();
				%>
				$("#pageSizeButt").val("<%=vPageSize%>")
			})
			
	</script>
  <style>
		table{
			height: 100px;
			margin: 80px auto;
			margin-bottom:20px;
			text-align: center;
		}
		caption{
			margin: 30px;
		}
		thead th,td{
			width:100px;
		}
 		ul{
			position: fixed;
			left: 27%;
			top: auto;			
			text-decoration: none;
		} 
		li{
			margin:5px;
			list-style: none;
			display: inline;
		}
		#goButt{
			width:30px;
		}
 		#dropPages{
			width: 65px;
			height: 23px; 
		} 
		a{text-decoration:none;}
	</style>
  
  <body>
  	<s:form action="paging"  theme="simple">
  		<s:submit value="sumbit"/>
  	</s:form>
	<table style="border-bottom:gainsboro solid 1px;border-top:gainsboro solid 1px;">
			<caption>学生信息表</caption>
			<thead>
				<th>学号</th>
				<th>姓名</th>
				<th>籍贯</th>
				<th>专业</th>
				<th>电话</th>
			</thead>
			
			<s:iterator value="#request.list" id="stu">
		   	<tr>
		   		<td><s:property value="#stu.sno" /></td>
		   		<td><s:property value="#stu.name" /></td>
		   		<td><s:property value="#stu.residence" /></td>
		   		<td><s:property value="#stu.major" /></td>
		   		<td><s:property value="#stu.phone" /></td>
		   	</tr>
	   		</s:iterator>

		</table>
		<s:form action="paging" method="post" theme="simple">
		<ul>
			<s:set name="page" value="#request.paging"/><!-- 获取分页信息 -->
			<li>
				<s:if test="#page.hasFirst">
					<s:a href="paging.action?pageNow=1">
						<input type="button" value="首页" />
					</s:a>
				</s:if>
			</li>
			<li>
				<s:if test="#page.hasPre">
					<a href="paging.action?pageNow=<s:property value="#page.pageNow-1"/>">
						<input type="button" value="上一页" />
					</a>
				</s:if>
			</li>
			<li>
				共<s:property value="#page.pageNow"/>/<s:property value="#page.totalPages"/>页
				&nbsp;&nbsp;
				转到<s:textfield name="pageNow" size="1"/>页 
				<s:submit value="Go" id="goButt"/>
			</li>
			<li>每页
				<select name="pageSize" onchange="pageSizeChange()" id="pageSizeButt">
					<option value="3">3</option>
					<option value="4">4</option>
					<option value="5">5</option>
					<option value="10">10</option>
				</select>
				条记录
			</li>
			<li>
				<s:if test="#page.hasNext">
					<a href="paging.action?pageNow=<s:property value="#page.pageNow+1"/>">
						<input type="button" value="下一页" />
					</a>
				</s:if>
			</li>
			<li>
				<s:if test="#page.hasLast">
					<a href="paging.action?pageNow=<s:property value="#page.totalPages"/>">
						<input type="button" value="尾页" />
					</a>
				</s:if>
			</li>
		</ul>
		</s:form>   
  </body>
</html>

8、测试结果

起初访问jsp页面没有数据，后台也没有报错。调试发现action类没有执行。原因是jsp没有发送请求，可通过修改添加空表单，点击提交链接到action完成初始化（后来才想到其实可以直接访问action完成初始化）。

实现的跳转页功能也用了表单action属性。

实现设置每页最大显示数用了select标签的onchange()函数功能，select显示的值稍微多绕了些才知道可以通过嵌入Java代码获取page对象拿到pageSize属性值，完成当前记录数的显示。

跳转到第二页（其中Go是表单提交）

点击尾页

修改每页十条，当前页会设置为1

如果想下载代码查看，请戳这里