Calling EJB3 deployed in Websphere AS7 from Standalone Java client _JAVA_编程开发_程序员俱乐部

1、先编写EJB3：

业务接口FirstEJBService

package com.first;

public interface FirstEJBService {
 void print(String msg);
}

EJB Local接口FirstEJBServiceBeanLocal

package com.first;

import javax.ejb.Local;

@Local
public interface FirstEJBServiceBeanLocal extends FirstEJBService {
}

EJB Remote接口FirstEJBServiceBeanRemote

package com.first;

import javax.ejb.Remote;

@Remote
public interface FirstEJBServiceBeanRemote extends FirstEJBService {
}

业务实现类FirstEJBServiceBean

package com.first;

import javax.ejb.Local;
import javax.ejb.Remote;
import javax.ejb.Stateless;

@Stateless(mappedName = "FirstEJBServiceBean")
@Local({ FirstEJBServiceBeanLocal.class })
@Remote({ FirstEJBServiceBeanRemote.class })
public class FirstEJBServiceBean implements FirstEJBService {

	@Override
	public void print(String msg) {
		System.out.println("FirstEJBService echo : " + msg);
	}

}

2、打包成jar后，发布到Websphere中；

3、查看JNDI
在cmd下调用WebSphere\AppServer\bin目录中dumpNameSpace.bat，可以查看到所有的JNDI，找到该EJB对应的JNDI全称；

4、编写Standalone Java client

package com.ejbclient.first;

import java.util.Properties;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;

import com.first.FirstEJBService;

public class FirstEJBClient {

	/**
	 * @param args
	 * @throws NamingException
	 */
	public static void main(String[] args) throws NamingException {
		Properties env = new Properties();
		env.put(Context.INITIAL_CONTEXT_FACTORY,
				"com.ibm.websphere.naming.WsnInitialContextFactory");
		env.put(Context.PROVIDER_URL, "iiop://localhost:2809");
		InitialContext context = new InitialContext(env);

		Object result = context
				.lookup("ejb/FirstEJB/FirstEJB.jar/FirstEJBServiceBean#com.first.FirstEJBServiceBeanRemote");

		FirstEJBService service = (FirstEJBService) javax.rmi.PortableRemoteObject
				.narrow(result, FirstEJBService.class);

		service.print("Hello EJB");
	}

}

client中，需要com.ibm.websphere.naming.WsnInitialContextFactory类，该类存在于WebSphere\AppServer\runtimes目录下的com.ibm.ws.admin.client_7.0.0.jar中，运行的时候需要在classpath中加上该jar；

到这并没有结束，由于Client与EJB不在同一个JVM中，所以还需要调用WebSphere\AppServer\bin目录中createEJBStubs.bat创建EJB stub：

createEJBStubs.bat com.first.FirstEJBService  -cp .

在运行的时候，将createEJBStubs.bat产生的_FirstEJBService_Stub.class放入classpath中，否则会产生异常：

java.lang.ClassCastException: org.omg.stub.java.rmi._Remote_Stub incompatible with com.first.FirstEJBService

或者

Exception in thread "P=556551:O=0:CT" java.lang.ClassCastException: Unable to load class: com.first._FirstEJBService_Stub