这里不会讨论EJB的概念，只讨论如何编写一个简单EJB，部署EJB，Weblogic与JBuilder的整合，本文先把介绍仅用文本编辑器编写一个最简单的EJB所需要的一切，以让大家一览EJB的概貌，然后才介绍如何把Weblogic与JBuilder整合起来，使用JBuilder开发Weblogic的EJB，我相信这样会得到很好的学习效果，因为这是我学习的路径，当然我会把我遇到的问题告诉大家，以免大家走弯路。
下面是一个最简单的EJB所需要的代码及XML说明，手工制作EJB的JAR包比较麻烦，在WIN2000下，我仿照例子制作了一个 build.cmd 批处理文件
weblogic-ejb-jar.xml
< xml version="1.0" >
< !DOCTYPE weblogic-ejb-jar PUBLIC -//BEA Systems, Inc.//DTD WebLogic 5.1.0 EJB//EN http://www.bea.com/servers/wls510/dtd/weblogic-ejb-jar.dtd >
< weblogic-ejb-jar >
< weblogic-enterprise-bean >
< ejb-name >HelloWorldBean< /ejb-name >
< caching-descriptor >
< max-beans-in-free-pool >100< /max-beans-in-free-pool >
< /caching-descriptor >
< jndi-name >hello.HelloWorld< /jndi-name >
< /weblogic-enterprise-bean >
< /weblogic-ejb-jar
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ejb-jar.xml
< xml version="1.0" encoding="GBK" >
< !DOCTYPE ejb-jar PUBLIC -//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 1.1//EN http://java.sun.com/j2ee/dtds/ejb-jar_1_1.dtd >
< ejb-jar >
< enterprise-beans >
< session >
< ejb-name >HelloWorldBean< /ejb-name >
< home >hello.HelloWorldHome< /home >
< remote >hello.HelloWorld< /remote >
< ejb-class >hello.HelloWorldBean< /ejb-class >
< session-type >Stateless< /session-type >
< transaction-type >Container< /transaction-type >
< /session >
< /enterprise-beans >
< assembly-descriptor >
< container-transaction >
< method >
< ejb-name >HelloWorldBean< /ejb-name >
< method-name >*< /method-name >
< /method >
< trans-attribute >Required< /trans-attribute >
< /container-transaction >
< /assembly-descriptor >
< /ejb-jar >
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package hello;
import java.rmi.*;
import javax.ejb.*;
public class HelloWorldBean implements SessionBean {
private SessionContext sessionContext;
public void ejbCreate() {
}
public void ejbRemove() {
}
public void ejbActivate() {
}
public void ejbPassivate() {
}
public void setSessionContext(SessionContext context) {
sessionContext = context;
}
public String getHelloWorld(){
return "Hello World!";
}
}
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HelloWorld.java
package hello;
import java.rmi.*;
import javax.ejb.*;
public interface HelloWorld extends EJBObject {
public java.lang.String getHelloWorld() throws RemoteException;
}
--------------------------------------------------------------------------------
HelloWorldHome.java
package hello;
import java.rmi.*;
import javax.ejb.*;
public interface HelloWorldHome extends EJBHome {
public HelloWorld create() throws RemoteException, CreateException;
}
--------------------------------------------------------------------------------
HelloWorldBean.java
package hello;
import java.rmi.*;
import javax.ejb.*;
public class HelloWorldBean implements SessionBean {
private SessionContext sessionContext;
public void ejbCreate() {
}
public void ejbRemove() {
}
public void ejbActivate() {
}
public void ejbPassivate() {
}
public void setSessionContext(SessionContext context) {
sessionContext = context;
}
pub