jpa之hibernate4.2.4之tomcat6.0测试

来源：互联网发布：美工网编辑：程序博客网时间：2024/04/26 15:56

这里有jpa的很多例子 http://www.objectdb.com/java/jpa/persistence/store 是很好的学习资料

开发环境:myeclipse 10.0

服务器:tomcat 6.0

oracle:11g

hibernate版本:4.2.4

1.新建名为JpaWeb的web工程添加依赖的jar包添加配置文件详细步骤前面博客已有提到这里就不说了

persistence.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence"        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"        xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"        version="2.0">    <persistence-unit name="under">        <properties>        <property name="hibernate.connection.driver_class" value="oracle.jdbc.driver.OracleDriver"/>        <property name="hibernate.connection.username" value="under_test" />         <property name="hibernate.connection.password" value="under_test" />         <property name="hibernate.connection.url" value="jdbc:oracle:thin:@localhost:1521:ganew" />         <property name="hibernate.hbm2ddl.auto" value="update" />         <property name="hibernate.show_sql" value="true" />        <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle10gDialect" />        </properties>    </persistence-unit></persistence>

2.修改index.jsp文件如下:

<%@page import="com.bean.Vistor"%><%@ page language="java" import="java.util.*" pageEncoding="gbk"%><%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">--><script type="text/javascript">function check(){if(document.getElementById("nameid").value=="") { alert('姓名不能为空'); return false;}if(document.getElementById("hobbyid").value=="") { alert('爱好不能为空'); return false;}document.getElementById("vis").submit();}</script>  </head>    <body>     <form method="post" action="<%=request.getContextPath() %>/DealCommit" id="vis">      姓名:<input type="text" name="name" id="nameid"> <br/>     爱好:<input type="text" name="hobby" id="hobbyid"><br/>     <input type="button" value="提交" onclick="check();">     </form>     <hr/>     <ol>     <%     List<Vistor> list=(List<Vistor>)request.getAttribute("list");     if(list!=null) {     for(Vistor vistor:list) { %>       <li><%=vistor %></li>      <%}       }%>      </ol>  </body></html>

上面页面有一个表单用户可以输入姓名和爱好提交到servlet之后会将系统中所有登陆的记录全部显示在界面上

DealCommit的servlet实现

packagecom.undergrowth;

importjava.io.IOException;

importjava.io.PrintWriter;

importjava.util.List;

importjavax.persistence.EntityManager;

importjavax.persistence.EntityManagerFactory;

importjavax.persistence.Query;

importjavax.servlet.ServletException;

importjavax.servlet.http.HttpServlet;

importjavax.servlet.http.HttpServletRequest;

importjavax.servlet.http.HttpServletResponse;

importcom.bean.Vistor;

public classDealCommit extends HttpServlet {

/**

* Constructor of theobject.

public DealCommit() {

super();

}

/**

* Destruction of theservlet. <br>

public void destroy(){

super.destroy(); //Just puts "destroy" string in log

// Put your code here

}

/**

* The doGet method ofthe servlet. <br>

* This method iscalled when a form has its tag value method equals to get.

* @param request therequest send by the client to the server

* @param response theresponse send by the server to the client

* @throwsServletException if an error occurred

* @throws IOExceptionif an error occurred

public voiddoGet(HttpServletRequest request, HttpServletResponse response)

throwsServletException, IOException {

request.setCharacterEncoding("gbk");

EntityManagerFactoryfactory=(EntityManagerFactory)getServletContext().getAttribute("factory");

EntityManagermanager=factory.createEntityManager();

try {

Stringname=request.getParameter("name");

Stringhobby=request.getParameter("hobby");

manager.getTransaction().begin();

manager.persist(newVistor(name, hobby));

manager.getTransaction().commit();

//获取所有记录

Queryquery=manager.createQuery("select v from Vistor v");

List<Vistor>list=query.getResultList();

request.setAttribute("list",list);

request.getRequestDispatcher("/index.jsp").forward(request,response);

} catch (Exception e){

e.printStackTrace();

}finally{

manager.close();

}

/**

* The doPost methodof the servlet. <br>

* This method iscalled when a form has its tag value method equals to post.

* @param request therequest send by the client to the server

* @param response theresponse send by the server to the client

* @throwsServletException if an error occurred

* @throws IOExceptionif an error occurred

public voiddoPost(HttpServletRequest request, HttpServletResponse response)

throwsServletException, IOException {

this.doGet(request,response);

}

/**

* Initialization ofthe servlet. <br>

* @throwsServletException if an error occurs

public void init()throws ServletException {

// Put your code here

}

在上面的servlet中从应用程序级别获取了factory对象因为在应用web启动的时候注册了一个servletcontextlistener的实现类这个实现类就是在应用启动时初始化了一个factory的实例存入了应用程序的属性中

并且将用户提交的姓名还有爱好存入的数据库中并且将数据库中已有的对象全部查询出来返回给index.jsp页面显示

JpaListener的监听器代码如下:

应用启动的时候获取EntityManagerFactory实例存入application的属性中应用关闭的时候关闭EntityManagerFactory的实例

packagecom.undergrowth;

importjavax.persistence.EntityManagerFactory;

importjavax.persistence.Persistence;

importjavax.servlet.ServletContextEvent;

importjavax.servlet.ServletContextListener;

public classJpaListener implements ServletContextListener {

@Override

public voidcontextDestroyed(ServletContextEvent arg0) {

// TODOAuto-generated method stub

EntityManagerFactoryfactory=(EntityManagerFactory)arg0.getServletContext().getAttribute("factory");

factory.close();

}

@Override

public voidcontextInitialized(ServletContextEvent arg0) {

// TODO Auto-generatedmethod stub

EntityManagerFactoryfactory=Persistence.createEntityManagerFactory("under");

arg0.getServletContext().setAttribute("factory",factory);

}

当然还需要在web.xml中加入监听器的配置项如下:

<listener-class>com.undergrowth.JpaListener</listener-class>

</listener>

再来看看这里的实体对象 Vistor的实现代码:

package com.bean;import java.util.Date;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.Lob;import javax.persistence.Temporal;import javax.persistence.TemporalType;@Entitypublic class Vistor {@Id @GeneratedValueprivate Integer id;@Column(length=12,nullable=false)private String name;@Lob private String hobby;@Temporal(TemporalType.TIMESTAMP)private Date loginTime=new Date(System.currentTimeMillis());public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getHobby() {return hobby;}public void setHobby(String hobby) {this.hobby = hobby;}public Date getLoginTime() {return loginTime;}public void setLoginTime(Date loginTime) {this.loginTime = loginTime;}public Vistor(){}public Vistor(String name, String hobby) {super();this.name = name;this.hobby = hobby;}@Overridepublic String toString() {return  name + "\t" + hobby+ "\t" + loginTime.toLocaleString();}}

index.jsp效果图: