/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.tuscany.sca.binding.ejb.util;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.rmi.RemoteException;
import java.rmi.UnexpectedException;
import javax.ejb.CreateException;
import javax.ejb.EJBLocalHome;
import javax.naming.NamingException;
import javax.rmi.CORBA.Util;
import org.omg.CORBA.SystemException;
import org.omg.CORBA.portable.ApplicationException;
import org.omg.CORBA.portable.ObjectImpl;
import org.omg.CORBA.portable.RemarshalException;
import org.omg.stub.java.rmi._Remote_Stub;
import org.oasisopen.sca.ServiceRuntimeException;
/**
* Factor class that is used to create EJB Proxies.
*
* @version $Rev: 738490 $ $Date: 2009-01-28 14:07:54 +0000 (Wed, 28 Jan 2009) $
*/
final class EJBObjectFactory {
private EJBObjectFactory() {
}
/**
* Get either a generated of dynamic EJB stub using the specified JNDI
* properties.
* <p>
* The returned stub will implement the specified stubInterface Interface.
* If the underlying EJB stub is not assignable from the specified
* stubInterface then a proxy is used to convert between the two.
* <p>
* The returned EJB stub may be either the pregenerated EJB stub or a
* dynamic stub. This allows a client to invoke an EJB without requiring any
* of the pregenerated EJB stub classes be available in the classpath.
* <p>
*/
static Object createStub(NamingEndpoint namingEndpoint, InterfaceInfo ejbInterface) throws NamingException,
RemoteException, CreateException {
EJBLocator locator = namingEndpoint.getLocator();
Object homeObject = locator.locate(namingEndpoint.getJndiName());
/*
* The type of the object returned from the lookup is as follows: If the
* generated stub exists on the classpath, it's an instance of that
* type, otherwise, "org.omg.stub.java.rmi._Remote_Stub" or
* "org.omg.stub.javax.ejb._EJBHome_Stub"
*/
Object stub = getEJBStub(homeObject, ejbInterface);
// Cache dynamic stub only
return stub;
}
/**
* @param homeObject
* @param ejbHomeClass
* @return
* @throws RemoteException
*/
private static Object getEJBStub(Object homeObject, InterfaceInfo ejbInterface) throws RemoteException,
CreateException {
Object stub = null;
// Get the business interface of the EJB
Class ejbInterfaceClass = null;
try {
ejbInterfaceClass = Thread.currentThread().getContextClassLoader().loadClass(ejbInterface.getName());
} catch (ClassNotFoundException e) {
// ignore
}
if (ejbInterfaceClass != null && ejbInterfaceClass.isInstance(homeObject)) {
// EJB 3
stub = homeObject;
} else if (homeObject instanceof EJBLocalHome) {
// Local EJB
stub = createEJBLocalObject(homeObject);
} else {
// Handle dynamic stub
if (homeObject instanceof ObjectImpl) {
ObjectImpl objectImpl = (ObjectImpl)homeObject;
stub = createEJBObject(objectImpl);
}/**
* Above checks will be satisfied if Bean is running on servers like WebSphere. With this
* logic, client (SCA composite with EJB ref binding) doesn't need to include home class or
* client stubs.
*
* Below check is needed SCA composite with EJB ref binding is accessing openEJB implementation.
* For e.g if the bean is running on Geronimo.
*/
else if ((javax.rmi.PortableRemoteObject.narrow(homeObject, javax.ejb.EJBHome.class)) instanceof javax.ejb.EJBHome) {
stub = createEJBObjectFromHome(homeObject);
} else
throw new ServiceRuntimeException("Invalid stub type: " + homeObject.getClass());
}
return stub;
}
/**
* Create a pre-generated EJB stub
*
* @param homeObject
* @return
* @throws RemoteException
*/
static private Object createEJBLocalObject(Object homeObject) throws RemoteException {
Object stub = null;
try {
// Find the "create()" method
Method createMethod = homeObject.getClass().getMethod("create", null);
// Create an EJB object
stub = createMethod.invoke(homeObject, null);
} catch (NoSuchMethodException e) {
// "create()" method not found, it's still a dynamic stub
stub = null;
} catch (InvocationTargetException e) {
throw new RemoteException(e.getTargetException().toString());
} catch (Exception e) {
throw new RemoteException(e.toString());
}
return stub;
}
/**
* Here homeObject is instance of EJBHome
*
* @param homeObject
* @return
* @throws RemoteException
*/
private static Object createEJBObjectFromHome(Object homeObject) throws RemoteException {
Object stub = null;
try {
// Find the "create()" method
Method createMethod = homeObject.getClass().getMethod("create", null);
// Create an EJB object
stub = createMethod.invoke(homeObject, null);
} catch (NoSuchMethodException e) {
// "create()" method not found, it's still a dynamic stub
stub = null;
} catch (InvocationTargetException e) {
throw new RemoteException(e.getTargetException().toString());
} catch (Exception e) {
throw new RemoteException(e.toString());
}
return stub;
}
/**
* Create an EJBObject using RMI/IIOP APIs
*
* @param ejbHomeObject
* @return The EJBObject remote stub
* @throws CreateException
* @throws RemoteException
*/
private static Object createEJBObject(ObjectImpl ejbHomeObject) throws CreateException, RemoteException {
try {
org.omg.CORBA_2_3.portable.InputStream in = null;
try {
org.omg.CORBA.portable.OutputStream out = ejbHomeObject._request("create", true);
in = (org.omg.CORBA_2_3.portable.InputStream)ejbHomeObject._invoke(out);
// The Remote stub should be available in JDK
// TODO: [rfeng] Work around an issue in Apache Yoko which doesn't understand the org.omg.stub.*
return in.read_Object(_Remote_Stub.class);
} catch (ApplicationException ex) {
in = (org.omg.CORBA_2_3.portable.InputStream)ex.getInputStream();
String id = in.read_string();
if (id.equals("IDL:javax/ejb/CreateEx:1.0")) {
throw (CreateException)in.read_value(CreateException.class);
}
throw new UnexpectedException(id);
} catch (RemarshalException ex) {
return createEJBObject(ejbHomeObject);
} finally {
ejbHomeObject._releaseReply(in);
}
} catch (SystemException ex) {
throw Util.mapSystemException(ex);
}
}
}