Spring+Hibernate+Struts實現(xiàn)分頁
Spring集成Hibernate,使得SessionFactory的管理更加方便,可以方便地獲取到一個HibernateTempalte的模板實例,對數(shù)據(jù)庫的操作非常方便。
Spring集成Struts,先把Struts的Action用Spring的ActionSupport抽象出來,比如定義一個名稱為SpringAction的的ActionSupport的子類,其中SpringAction中啟動IoC容器,通過ApplicationContext獲取業(yè)務bean。這需要使用一個Struts插件來初始化IoC容器,從而獲取到一個ApplicationContext。可以通過讓每個具體的Action(每個具體的Action意思是實現(xiàn)Struts的Action的子類)都繼承自上面定義的SpringAction,實現(xiàn)對模型的調(diào)用,以及派發(fā)視圖。
下面通過實現(xiàn)分頁來說明。
實現(xiàn)思路
Spring集成Hibernate,直接使用Hibernatede配置文件hibernate.cfg.xml,注入一個SessionFactory,從而在DAO中獲取到一個HibernateTemplate。
(注意,下面工程結構中,實際上包org.shirdrn.spring.dao及其包org.shirdrn.spring.daoImpl中的接口和類并沒有使用到。)
org.shirdrn.spring.util.Page類是一個頁面的實體類,沒有加入任何分頁邏輯,而實現(xiàn)分頁邏輯的抽象是在org.shirdrn.spring.util.PageUtil類中,該類是對所有需要實現(xiàn)分頁的業(yè)務對象分頁邏輯的抽象,而且PageUtil類繼承自HibernateDaoSupport類,它是一個具有特殊業(yè)務需(分頁)要的DAO,只是為獲取分頁結果而定義的,只要注入一個SessionFactory就可以方便地檢索數(shù)據(jù)庫了。所有的具體的業(yè)務對象如果需要分頁顯示的數(shù)據(jù)庫記錄,都可以從繼承PageUtil類。
包org.shirdrn.spring.pages中有一個MyUserPage類,該類繼承自PageUtil類,是一個具體實現(xiàn)分頁邏輯的類,只對MyUser實體(對應數(shù)據(jù)庫中myUser表)的分頁進行處理。
開發(fā)環(huán)境
Windows 2003 SP2 + SQL Server 2000 + Eclipse 3.2 + JDK 1.5 + MyEclipse 5.0 + Tomcat 5.5.9 + Spring 2.0 + Hibernate 3.0 + Struts 1.2
工程結構
SpringHibernateStrutsPage
│ .classpath
│ .myhibernatedata
│ .mymetadata
│ .mystrutsdata
│ .project
│ .springBeans
│
├─.myeclipse
├─src
│ │ hibernate.cfg.xml
│ │
│ └─org
│ └─shirdrn
│ ├─spring
│ │ ├─action
│ │ │ SpringAction.java
│ │ │
│ │ ├─dao
│ │ │ │ MyUserDAO.java
│ │ │ │
│ │ │ └─impl
│ │ │ MyUserDAOImpl.java
│ │ │
│ │ ├─entity
│ │ │ MyUser.hbm.xml
│ │ │ MyUser.java
│ │ │
│ │ ├─pages
│ │ │ MyUserPage.java
│ │ │
│ │ └─util
│ │ Page.java
│ │ PageUtil.java
│ │
│ └─struts
│ │ ApplicationResources.properties
│ │
│ └─action
│ ListMyUsersAction.java
│
└─WebRoot
│ listmyusers.jsp
│
├─META-INF
│ MANIFEST.MF
│
└─WEB-INF
│ .struts-config.mex
│ action-servlet.xml
│ struts-bean.tld
│ struts-config.xml
│ struts-html.tld
│ struts-logic.tld
│ validator-rules.xml
│ web.xml
│
├─classes
│ │ hibernate.cfg.xml
│ │
│ └─org
│ └─shirdrn
│ ├─spring
│ │ ├─action
│ │ │ SpringAction.class
│ │ │
│ │ ├─dao
│ │ │ │ MyUserDAO.class
│ │ │ │
│ │ │ └─impl
│ │ │ MyUserDAOImpl.class
│ │ │
│ │ ├─entity
│ │ │ MyUser.class
│ │ │ MyUser.hbm.xml
│ │ │
│ │ ├─pages
│ │ │ MyUserPage$1.class
│ │ │ MyUserPage.class
│ │ │
│ │ └─util
│ │ Page.class
│ │ PageUtil.class
│ │
│ └─struts
│ │ ApplicationResources.properties
│ │
│ └─action
│ ListMyUsersAction.class
│
└─lib
開發(fā)過程
(1) Hibernate準備
編寫Hibernate配置文件hibernate.cfg.xml:
<?xml version='1.0' encoding='UTF-8'?> <!-- Generated by MyEclipse Hibernate Tools. --> <session-factory> </session-factory> </hibernate-configuration> 實現(xiàn)Hibernate映射文件MyUser.hbm.xml,及其對應的POJO: 這個非常容易,就省略了。 (2) Spring集成Hibernate 在/WEB-INF/目錄下面,新建一個action-servlet.xml的Spring配置文件,因為后面要和Struts集成,所以根據(jù)格式<SERVLETNAME>-servlet.xml,應該使用Struts的Servlet映射名稱。 Spring集成Hibernate,在action-servlet.xml中配置如下: <bean id="mySessionFactory" (3) 頁面實體及分頁邏輯實現(xiàn) Page是一個頁面實體類,如下: package org.shirdrn.spring.util; import java.util.List; public class Page { public int getCurrentPage() { public void setCurrentPage(int currentPage) { public List getList() { public void setList(List list) { public int getNextPage() { public void setNextPage(int nextPage) { public int getPageSize() { public void setPageSize(int pageSize) { public int getPrePage() { public void setPrePage(int prePage) { public int getRowCount() { public void setRowCount(int rowCount) { public int getTotalPage() { public void setTotalPage(int totalPage) { public boolean isHasNextPage() { public void setHasNextPage(boolean hasNextPage) { public boolean isHasPreviousPage() { public void setHasPreviousPage(boolean hasPreviousPage) { PageUtil類是一個分頁邏輯的抽象,需要分頁的話,只需要繼承自它便可以方便地實現(xiàn)分頁,可見,PageUtil可以重用,如下所示: package org.shirdrn.spring.util; import org.shirdrn.spring.pages.MyUserPage; public class PageUtil extends HibernateDaoSupport { (4) 具體的業(yè)務對象分頁實現(xiàn) 這里,MyUser類是一個POJO,查詢出結果需要分頁顯示。 MyUser的分頁實現(xiàn)類為MyUserPage類,它應該繼承PageUtil類。因為PageUtil類繼承了HibernateDaoSupport類,所以需要注入一個SessionFactory,在action-servlet.xml中配置如下所示: <bean id="myUserPage" abstract="false" 具體地,MyUserPage類實現(xiàn)如下所示: package org.shirdrn.spring.pages; import java.sql.SQLException; import org.hibernate.HibernateException; public class MyUserPage extends PageUtil { 上面實現(xiàn),使用了HQL檢索方式實現(xiàn)查詢數(shù)據(jù)庫記錄。 在MyUserPage中可以使用帶參數(shù)的構造方法實現(xiàn)頁面的初始化,但是在使用構造方法注入的時候,很容易出錯,而且不直觀,所以直接通過調(diào)用實現(xiàn)的一個init方法來初始化。 (6) Spring集成Struts 需要在Struts的配置文件struts-config.xml中配置一個插件,如下所示: <?xml version="1.0" encoding="UTF-8"?> <struts-config> 只要這樣配置好,Struts才能初始化Spring的IoC容器,否則Action無法工作。 (7) Action的實現(xiàn) SpringAction繼承了Spring的ActionSupport,我們將用它來替代所有繼承自Struts的Action類的Action。SpringAction的實現(xiàn)如下所示: package org.shirdrn.spring.action; import org.shirdrn.spring.pages.MyUserPage; public class SpringAction extends ActionSupport { 這里,SpringAction就實現(xiàn)了獲取一個MyUserPage的實例的功能,從而通過這個實例實現(xiàn)分頁。 然后,實現(xiàn)一個ListMyUsersAction類,它繼承自SpringAction,能夠啟動Spring的IoC容器,并且獲取一個MyUserPage的實例。ListMyUsersAction類的實現(xiàn)如下所示: package org.shirdrn.struts.action; import java.util.List; import javax.servlet.http.HttpServletRequest; import org.apache.struts.action.ActionForm; public class ListMyUsersAction extends SpringAction { public ActionForward execute(ActionMapping mapping, ActionForm form, (8) 視圖的實現(xiàn) JSP頁面,使用Struts標簽實現(xiàn)分頁頁面的顯示。 JSP頁面listmyusers.jsp如下所示: <%@ page contentType="text/html;charset=utf-8"%> (9) 部署Web應用 配置web.xml文件,如下所示: <?xml version="1.0" encoding="UTF-8"?> 就可以看到數(shù)據(jù)的分頁顯示,效果如圖所示: OK,就這么容易。
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"
<hibernate-configuration>
<property name="dialect">
org.hibernate.dialect.SQLServerDialect
</property>
<property name="connection.url">
jdbc:microsoft:sqlserver://localhost:1433;databasename=shirdrn
</property>
<property name="connection.username">sa</property>
<property name="connection.password">111111</property>
<property name="connection.driver_class">
com.microsoft.jdbc.sqlserver.SQLServerDriver
</property>
<property name="myeclipse.connection.profile">MSSQL</property>
<property name="show_sql">true</property>
<mapping resource="org/shirdrn/spring/entity/MyUser.hbm.xml" />
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="configLocation">
<value>classpath:hibernate.cfg.xml</value>
</property>
</bean>
private int pageSize;
private int totalPage;
private int rowCount;
private int currentPage;
private int prePage;
private int nextPage;
private boolean hasNextPage; // 是否有下一頁
private boolean hasPreviousPage; // 是否有前一頁
private List list;
public Page(){
this.pageSize = 10;
}
return currentPage;
}
this.currentPage = currentPage;
}
return list;
}
this.list = list;
}
return nextPage;
}
this.nextPage = nextPage;
}
return pageSize;
}
this.pageSize = pageSize;
}
return prePage;
}
this.prePage = prePage;
}
return rowCount;
}
this.rowCount = rowCount;
}
return totalPage;
}
this.totalPage = totalPage;
}
return hasNextPage;
}
this.hasNextPage = hasNextPage;
}
return hasPreviousPage;
}
this.hasPreviousPage = hasPreviousPage;
}
}
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
public Page page;
public int start;
public PageUtil(){
}
public void setPreOrNextBoolean(){
if(page.getCurrentPage()<=1){
page.setHasPreviousPage(false);
}
else{
page.setHasPreviousPage(true);
}
if(page.getCurrentPage()>=page.getTotalPage()){
page.setHasNextPage(false);
}
else{
page.setHasNextPage(true);
}
}
public void setCurrentPage(){
if(start<1){
page.setCurrentPage(1);
}
if(start>page.getTotalPage()){
page.setCurrentPage(page.getTotalPage());
}
page.setCurrentPage(start);
}
public void setPrePage(){
page.setPrePage(page.getCurrentPage()-1);
}
public void setNextPage(){
page.setNextPage(page.getCurrentPage()+1);
}
public void setTotalPage(){
int rowCount = getRowCount();
int pageSize = page.getPageSize();
if(rowCount>pageSize){
if(rowCount%pageSize == 0){
page.setTotalPage(rowCount/pageSize);
}
else{
page.setTotalPage(1+(rowCount/pageSize));
}
}
else{
page.setTotalPage(1);
}
}
public void setRowCount(){
page.setRowCount(getRowCount());
}
public int getRowCount(){
return 0;
}
public int getStartIndex(){
int startIndex = 0;
if(start<0){
startIndex = 0;
}
else{
if(start>page.getTotalPage()){
startIndex = page.getPageSize()*(page.getTotalPage()-1);
}
else{
startIndex = page.getPageSize()*(start-1);
}
}
return startIndex;
}
public Page getPage(){
return page;
}
}
class="org.shirdrn.spring.pages.MyUserPage"
lazy-init="default" autowire="default" dependency-check="default">
<property name="sessionFactory">
<ref bean="mySessionFactory"/>
</property>
</bean>
</beans>
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.shirdrn.spring.util.Page;
import org.shirdrn.spring.util.PageUtil;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.orm.hibernate3.HibernateCallback;
private String hql;
public void init(int start,String hql){ // 通過init方法實現(xiàn)一個頁面的初始化
page = new Page();
this.hql = hql;
this.start = start;
setRowCount();
setTotalPage();
setCurrentPage();
setPrePage();
setNextPage();
setPreOrNextBoolean();
}
@Override
public int getRowCount(){
List list = getHibernateTemplate().find(hql);
if(list.isEmpty()){
return 0;
}
return list.size();
}
@Override
public Page getPage(){
List list = (List)getHibernateTemplate().execute(new HibernateCallback(){
public Object doInHibernate(Session session) throws HibernateException, SQLException {
Query query = session.createQuery(hql);
query.setFirstResult(getStartIndex());
query.setMaxResults(page.getPageSize());
return query.list();
}
});
page.setList(list);
return page;
}
}
<!DOCTYPE struts-config PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 1.2//EN" "
<data-sources />
<form-beans />
<global-exceptions />
<global-forwards />
<action-mappings >
<action path="/listMyUsers" type="org.shirdrn.struts.action.ListMyUsersAction">
<forward
name="listmyusers"
path="/listmyusers.jsp"
redirect="true" />
</action>
</action-mappings>
<message-resources parameter="org.shirdrn.struts.ApplicationResources" />
<plug-in className="org.springframework.web.struts.ContextLoaderPlugIn">
<set-property property="contextConfigLocation"
value="/WEB-INF/action-servlet.xml"/>
</plug-in>
</struts-config>
import org.springframework.web.struts.ActionSupport;
public MyUserPage getMyUserPage(){
return (MyUserPage)getWebApplicationContext().getBean("myUserPage");
}
}
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.shirdrn.spring.action.SpringAction;
import org.shirdrn.spring.pages.MyUserPage;
import org.shirdrn.spring.util.Page;
HttpServletRequest request, HttpServletResponse response) {
int pno = (new Integer(request.getParameter("pno"))).intValue();
String hql = "from MyUser";
MyUserPage myUserPage = getMyUserPage();
myUserPage.init(pno, hql);
Page myUserOnePage = myUserPage.getPage();
List myUserList = myUserPage.getPage().getList();
HttpSession session = request.getSession();
session.setAttribute("myUserOnePage", myUserOnePage);
session.setAttribute("myUserList", myUserList);
return mapping.findForward("listmyusers");
}
}
<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html"%>
<%@ taglib uri="/WEB-INF/struts-bean.tld" prefix="bean"%>
<%@ taglib uri="/WEB-INF/struts-logic.tld" prefix="logic"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<html:html locale="true">
<head>
<base href="<%=basePath%>">
<title>查詢記錄列表</title>
<style type="text/css">
body{
background:#000000;
font-size:12px;
color:yellow;
}
a:link{
color:yellow;
text-decoration:none;
}
a:hover{
color:red;
text-decoration:none;
}
a:visited{
color:yellow;
text-decoration:none;
}
</style>
</head>
<body>
<table width="60%" align="center" bgcolor="green" border="1">
<tr>
<th colspan="10">MyUser查詢列表</th>
</tr>
<tr align="center">
<td width="20%"><b>ID</b></td>
<td width="20%"><b>姓名</b></td>
<td width="20%"><b>性別</b></td>
<td width="20%"><b>年齡</b></td>
<td width="20%"><b>住址</b></td>
</tr>
<logic:present name="myUserList">
<logic:iterate id="myUser" name="myUserList" type="org.shirdrn.spring.entity.MyUser">
<logic:present name="myUser">
<tr align="center">
<td width="20%" height="10"><bean:write name="myUser" property="id"/></td>
<td width="20%" height="10"><bean:write name="myUser" property="userName"/></td>
<td width="20%" height="10"><bean:write name="myUser" property="gender"/></td>
<td width="20%" height="10"><bean:write name="myUser" property="age"/></td>
<td width="20%" height="10"><bean:write name="myUser" property="addr"/></td>
</tr>
</logic:present>
</logic:iterate>
</logic:present>
</table>
<table align="center" width="60%" bgcolor="green" border="1">
<tr>
<td align="center" colspan="10">
<logic:present name="myUserOnePage">
<html:link page="/listMyUsers.do?pno=1">首頁</html:link>
<logic:equal name="myUserOnePage" property="hasPreviousPage" value="false">上一頁</logic:equal>
<logic:equal name="myUserOnePage" property="hasPreviousPage" value="true">
<a href="<%=path%>/listMyUsers.do?pno=<bean:write name="myUserOnePage" property="prePage"/>">上一頁</a>
</logic:equal>
每頁<bean:write name="myUserOnePage" property="pageSize"/>條記錄
共<bean:write name="myUserOnePage" property="rowCount"/>條記錄
當前第(<bean:write name="myUserOnePage" property="currentPage"/>/<bean:write name="myUserOnePage" property="totalPage"/>)頁
<logic:equal name="myUserOnePage" property="hasNextPage" value="false">下一頁</logic:equal>
<logic:equal name="myUserOnePage" property="hasNextPage" value="true">
<a href="<%=path%>/listMyUsers.do?pno=<bean:write name="myUserOnePage" property="nextPage"/>">下一頁</a>
</logic:equal>
<a href="<%=path%>/listMyUsers.do?pno=<bean:write name='myUserOnePage' property='totalPage'/>">末頁</a>
</logic:present>
</td>
</tr>
</table>
</body>
</html:html>
<web-app xmlns="http://localhost:8080/SpringHibernateStrutsPage/listMyUsers.do?pno=1