EJB3.0高速入门项目开发步骤

EJB3.0开发步骤

1.   开发环境

IDE开发工具：Eclipse Java EE IDE for Web Developers

EJB容器：jboss-4.2.3.GA

后台数据库：MysQL5.1

2.   开发步骤

2.1   在Eclipse中配置jboss-4.2.3.GA

1.  点击小三角，选中New server

2.  选中JBOSS AS4.2

3.  点击ADD。进行JBOSS配置

4.  在Home Directory中。点击Browser选择JBOSS4.2的安装文件夹，在JRE中配置JRE的安装文件夹，点击finish

在finish。就可以完毕对ＪＢＯＳＳ在Ｅｃｌｉｐｓｅ中的配置。

2.2   新建EJB3.0projecttitan

1.        右键－>Ｎｅｗ->Project

2.        选择EJB Project->next

3.        Project  name为“titan”，Targetruntime选择配置好的JBOSS4.2，EJB module version选择3.0，然后finish。新的EJB3.0project创建成功。

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2.3   项目开发

2.3.1 开发Cabin实体Bean

package com.titan.domain;

import javax.persistence.Column;

import javax.persistence.Entity;

import javax.persistence.Id;

import javax.persistence.Table;

@Entity//告知persistence provider这是一个映射到数据的实体类，而且能够受管于EntityManager服务。

@Table(name="CABIN")//告知EJB容器。beanclass 应该被映射到哪一张数据库表。

public
classCabin implementsjava.io.Serializable{

/**

*

*/

private
staticfinal
longserialVersionUID = 1L;

/**

*

*/

private
intid;

private String
name;

private
intdeckLevel;

private
intshipId;

private
intbedCount;

@Id//表示CAbin实体的主键，主键标志是必须的

@Column(name="ID")//定义怎样将成员属性映射到数据库表CABIN中的字段。并不是是必须的

public
intgetId() {

return
id;

}

public
voidsetId(int id) {

this.id =id;

}

@Column(name="NAME")

public String getName() {

return
name;

}

public
voidsetName(String name) {

this.name =name;

}

@Column(name="DECK_LEVEL")

public
intgetDeckLevel() {

return
deckLevel;

}

public
voidsetDeckLevel(int deckLevel) {

this.deckLevel= deckLevel;

}

@Column(name="SHIP_ID")

public
intgetShipId() {

returnshipId;

}

public
voidsetShipId(int shipId) {

this.shipId= shipId;

}

@Column(name="BED_COUNT")

public
intgetBedCount() {

return
bedCount;

}

public
voidsetBedCount(int bedCount) {

this.bedCount= bedCount;

}

}

2.3.2开发远程接口TravelAgentRemote

package com.titan.travelagent;

import javax.ejb.Remote;

import com.titan.domain.Cabin;

@Remote//表示这是一个远程接口

public
interfaceTravelAgentRemote {

public
voidcreateCabin(Cabin cabin);

public Cabin findCabin(int id);

}

2.3.3开发远程接口的实现Bean类TravelAgentBean（StatelessBean）

package com.titan.travelagent;

import javax.ejb.Stateless;

import javax.persistence.EntityManager;

import javax.persistence.PersistenceContext;

import com.titan.domain.Cabin;

@Stateless//表示这是一个无状态sessionbean

public
classTravelAgentBean implementsTravelAgentRemote {

//@PersistenceContext告知EJB容器，必须用一个EntityManager实例来设置manager数据成员。

@PersistenceContext(unitName="titan")
privateEntityManager
manager;

public
voidcreateCabin(Cabin cabin) {

// TODO Auto-generated method stub

manager.persist(cabin);

}

public Cabin findCabin(int id) {

// TODO Auto-generated method stub

return
manager.find(Cabin.class, id);

}

}

2.3.4在META-INF下创建文件persistence.xml文件

配置例如以下：

<?xml
version="1.0"encoding="UTF-8"
?>

<persistence
version="1.0"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/persistencehttp://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">

<persistence-unit
name="titan">

<jta-data-source>java:/titan</jta-data-source>

<properties>

<property
name="hibernate.hbm2ddl.auto"value="create-drop"/>

</properties>

</persistence-unit>

</persistence>

2.3.5在com.titan.clients包下开发客户端程序

packagecom.titan.clients;

importjavax.naming.InitialContext;

importjavax.naming.Context;

importjavax.naming.NamingException;

importjavax.rmi.PortableRemoteObject;

importcom.titan.domain.Cabin;

importcom.titan.travelagent.TravelAgentRemote;

importjava.util.Properties;

importjavax.rmi.PortableRemoteObject;

public classClient {

public static void main(String[]args){

try {

Context jndiContext=getInitialContext();

Objectref=jndiContext.lookup("TravelAgentBean/remote");

TravelAgentRemotedao=(TravelAgentRemote)

PortableRemoteObject.narrow(ref, TravelAgentRemote.class);

Cabin cabin_1=new Cabin();

cabin_1.setId(1);

cabin_1.setName("MasterSuite");

cabin_1.setDeckLevel(1);

cabin_1.setShipId(1);

cabin_1.setBedCount(3);

dao.createCabin(cabin_1);

Cabin cabin_2=dao.findCabin(1);

System.out.println(cabin_2.getId());

System.out.println(cabin_2.getName());

System.out.println(cabin_2.getShipId());

System.out.println(cabin_2.getDeckLevel());

System.out.println(cabin_2.getBedCount());

} catch (ClassCastException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (NamingException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

private static Context getInitialContext()throws NamingException {

// TODO Auto-generated method stub

Properties p=new Properties();

//...制定专有ＥＪＢ厂商的ＪＮＤＩ属性

p.put(Context.INITIAL_CONTEXT_FACTORY,"org.jnp.interfaces.NamingContextFactory");

p.put(Context.PROVIDER_URL, "://localhost:1099");

return newjavax.naming.InitialContext(p);

}

}

至此项目的client开发完毕。

2.4   配置MySql的datasource

1.  将mysql-connector-java-5.1.16.jar包放置到JBOSS_HOME\server\default\lib文件夹下.

2.  将配置好的mysql-ds.xml放到JBOSS_HOME\server\default\deploy文件夹下。配置例如以下：

<?

xmlversion="1.0" encoding="UTF-8"?>

<datasources>

<local-tx-datasource>

<jndi-name>titan</jndi-name>

<connection-url>jdbc:mysql://192.168.9.85:3306/titan</connection-url>

<driver-class>com.mysql.jdbc.Driver</driver-class>

<user-name>root</user-name>

<password>root</password>

<exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLExceptionSorter</exception-sorter-class-name>

<metadata>

<type-mapping>mySQL</type-mapping>

</metadata>

</local-tx-datasource>

</datasources>

2.4.1创建数据库

1、创建数据库titan

2、创建数据表cabin

DROP TABLE IFEXISTS `cabin`;

CREATE TABLEcabin (

ID int(11) NOT NULL,

NAME varchar(255) DEFAULT NULL,

DECK_LEVEL int(11) DEFAULT NULL,

SHIP_ID int(11) DEFAULT NULL,

BED_COUNT int(11) DEFAULT NULL,

PRIMARY KEY (`ID`)

)

3.   执行

1.  将titanproject公布到JBOSS。启动JBOSS

2.  打开client程序。右键->Run As->Java Application

3.  在数据库里能够查询到对应的数据记录，在控制台中能够看到对应的查询结果。