-- 作者：hongjunli
-- 发布时间：11/30/2007 9:11:00 AM
-- 史上最简单的EJB3示例教程[转帖]
虽然不是很完善，但是可以用来了解下EJB3的大致结构以及同EJB2的不同之处。 http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial I. Stateless Bean 部署在服务器端的Bean
KennyBean.java
[URL=http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial#]Toggle line numbers[/URL]
1 package test.ejb;
2 import javax.ejb.Stateless;
3 @Stateless
4 public class KennyBean implements Kenny {
5 public String say() {
6 return "Hello";
7 }
8 } Kenny.java
[URL=http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial#]Toggle line numbers[/URL]
1 package test.ejb;
2 import javax.ejb.Remote;
3 @Remote
4 public interface Kenny {
5 String say();
6
7 }
客户端 [URL=http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial#]Toggle line numbers[/URL]
1 package test.ejb;
2 import javax.naming.InitialContext;
3 import javax.naming.Context;
4 import java.util.Properties;
5 public class Main {
6 public static void main(String[] args) {
7 try {
8 Properties props = new Properties();
9 props.put("org.omg.CORBA.ORBInitialHost", "localhost");
10 props.put("org.omg.CORBA.ORBInitialPort", "37000");
11
12 InitialContext context = new InitialContext(props);
13 Kenny kenny = (Kenny)context.lookup(Kenny.class.getName());
14 System.out.println("Say something Kenny.");
15 System.out.println("Kenny: ".concat(kenny.say()));
16 }catch(Exception e) {
17 System.err.println("Error: ".concat(e.getMessage()));
18 }
19 }
20 }
运行结果 Say something Kenny.
Kenny: Hello II. Stateful Bean
将上面的例子稍加改动
部署在服务器端的Bean
KennyBean.java
[URL=http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial#]Toggle line numbers[/URL]
1
2 package test.ejb;
3
4 import javax.ejb.Stateful;
5 import javax.ejb.Init;
6 import javax.ejb.Remove;
7
8 @Stateful
9 public class KennyBean implements Kenny {
10
11 public String say() {
12 return "Hello";
13 }
14
15 @Init
16 public void create() {
17 System.out.println("Kenny comes.");
18 }
19
20 @Remove
21 public void remove() {
22 System.out.println("Kenny leaves.");
23 }
24
25 }
26
27 Kenny.java
[URL=http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial#]Toggle line numbers[/URL]
1
2 package test.ejb;
3
4 import javax.ejb.Remote;
5
6 @Remote
7 public interface Kenny {
8
9 String say();
10
11 void create();
12
13 void remove();
14
15 }
16
17
客户端 [URL=http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial#]Toggle line numbers[/URL]
1
2 package test.ejb;
3
4 import javax.naming.InitialContext;
5 import javax.naming.Context;
6 import java.util.Properties;
7
8 public class Main {
9
10 public static void main(String[] args) {
11
12 try {
13 Properties props = new Properties();
14
15 props.put("org.omg.CORBA.ORBInitialHost", "localhost");
16 props.put("org.omg.CORBA.ORBInitialPort", "3700");
17
18 InitialContext context = new InitialContext(props);
19 Kenny kenny = (Kenny)context.lookup(Kenny.class.getName());
20 kenny.create();
21 System.out.println("Say something Kenny.");
22 System.out.println("Kenny: ".concat(kenny.say()));
23 kenny.remove();
24 }catch(Exception e) {
25 System.err.println("Error: ".concat(e.getMessage()));
26 }
27 }
28
29 }
30
31
运行结果
客户端处显示
Say something Kenny.
Kenny: Hello
服务器端显示
Kenny comes.
Kenny leaves. III. Message Driven Bean 部署在服务器端的Bean
KennyInBox.java [URL=http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial#]Toggle line numbers[/URL]
1
2 package test.message.ejb;
3
4 import javax.ejb.MessageDriven;
5 import javax.jms.Message;
6 import javax.jms.MessageListener;
7 import javax.annotation.Resource;
8 import javax.ejb.MessageDrivenContext;
9
10 @MessageDriven(mappedName = "jms/Queue")
11 public class KennyInBox implements MessageListener {
12
13 @Resource
14 MessageDrivenContext mdc;
15
16 public KennyInBox() {
17 }
18
19 public void onMessage(Message message) {
20 System.out.println("Kenny received your message.");
21 }
22
23 }
24
客户端 [URL=http://linuxfire.com.cn/firewiki/SimplestEJB3Tutorial#]Toggle line numbers[/URL]
1
2 package test.message.ejb.client;
3
4 import javax.jms.Connection;
5 import javax.jms.QueueConnectionFactory;
6 import javax.jms.MessageProducer;
7 import javax.jms.Session;
8 import javax.jms.Queue;
9 import javax.jms.TextMessage;
10 import javax.naming.InitialContext;
11 import java.util.Properties;
12
13 public class Main {
14
15 public static void main(String[] args) {
16
17 Connection connection = null;
18 Session session = null;
19 MessageProducer messageProducer = null;
20 TextMessage message = null;
21
22 try {
23 Properties props = new Properties();
24
25 props.put("org.omg.CORBA.ORBInitialHost", "localhost");
26 props.put("org.omg.CORBA.ORBInitialPort", "3700");
27
28 InitialContext context = new InitialContext(props);
29 QueueConnectionFactory connectionFactory = (QueueConnectionFactory)context.lookup("jms/QueueFactory");
30 Queue queue = (Queue)context.lookup("jms/Queue");
31
32 connection = connectionFactory.createConnection();
33 session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
34 messageProducer = session.createProducer(queue);
35 message = session.createTextMessage();
36 message.setText("Hello");
37 messageProducer.send(message);
38 System.out.println("Message sent.");
39 }catch(Exception e) {
40 System.err.println("Error: ".concat(e.getMessage()));
41 }finally {
42 try {
43 connection.close();
44 }catch (Exception e0) {
45 System.out.println("Error: ".concat(e0.getMessage()));
46 }
47 System.exit(0);
48 }
49 }
50 }
51
52 客户端处显示
Message sent.
服务器端显示
Kenny received your message.
(待续...) --------------------------------------------------------------------------------
注： 笔者使用的工作环境 JDK 1.6.0
GlassFish 9.1 Netbeans 6.0 Beta 2
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