org.apache.beehive.controls.system.ejb.SessionEJBControlImpl Maven / Gradle / Ivy
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* 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.
*
* $Header:$
*/
package org.apache.beehive.controls.system.ejb;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import javax.ejb.EJBObject;
import javax.ejb.EJBLocalObject;
import org.apache.beehive.controls.api.ControlException;
import org.apache.beehive.controls.api.bean.ControlImplementation;
/**
* The SessionEJBControlImpl class is the control implementation class for
* Stateless/Stateful Session EJBs.
*
* Currently, this is a noop since no session-bean specific control APIs
* are defined, but having a unique control interface/impl class still allows
* JellyBeans to create two different control types.
*/
@ControlImplementation(assembler = EJBControlAssembler.class)
public class SessionEJBControlImpl
extends EJBControlImpl
implements SessionEJBControl, java.io.Serializable {
static final long serialVersionUID = 1L;
/**
* Override ejbControl.onCreate to perform additional processing
*/
public void onCreate() {
super.onCreate();
if (_beanType != EJBControlImpl.SESSION_BEAN)
throw new ControlException("Attempting to use a session bean control with a bean that is not a session bean");
}
/**
* Implements auto-create semantics for Session beans.
*/
protected Object resolveBeanInstance() {
// First, try to resolve from a cached EJB handle (if any)
Object fromHandle = resolveBeanInstanceFromHandle();
if (fromHandle != null)
return fromHandle;
// Find null arg create() on the home interface, and use it to get an instance
try {
/* todo: for efficiency, this could be done once per home interface and cached */
Method createMethod = _homeInterface.getMethod("create", new Class []{});
Object beanInstance = createMethod.invoke(_homeInstance, (Object[])null);
_autoCreated = true;
return beanInstance;
}
catch (NoSuchMethodException e) {
throw new ControlException("Cannot auto-create session bean instance because no null argument create() method exists. To use this bean, you will need to call create() directly with the appropriate parameters");
}
catch (InvocationTargetException e) {
_lastException = e.getTargetException();
throw new ControlException("Unable to create session bean instance", _lastException);
}
catch (Exception e) {
throw new ControlException("Unable to invoke home interface create method", e);
}
}
protected void releaseBeanInstance(boolean alreadyRemoved) {
//
// For session EJBs, releasing the instance implies the physical
// removal of the bean instance. If the bean was auto-created by
// the control, it has responsibility for deleting.
//
if (_beanInstance != null && _autoCreated && !alreadyRemoved) {
try {
if (EJBObject.class.isAssignableFrom(_beanInterface))
((EJBObject) _beanInstance).remove();
else
((EJBLocalObject) _beanInstance).remove();
}
/* RemoteException or RemoveException */
catch (Exception e) {
_lastException = e;
}
}
super.releaseBeanInstance(alreadyRemoved);
}
/**
* Set to true if the EJB instance was autocreated as a result of a bean method
* call (as opposed to direct invocation of the home create() method).
*/
private boolean _autoCreated = false;
}