/*******************************************************************************
* Copyright (c) 1998, 2015 Oracle and/or its affiliates. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* 05/16/2008-1.0M8 Guy Pelletier
* - 218084: Implement metadata merging functionality between mapping files
* 01/05/2010-2.1 Guy Pelletier
* - 211324: Add additional event(s) support to the EclipseLink-ORM.XML Schema
* 07/15/2010-2.2 Guy Pelletier
* -311395 : Multiple lifecycle callback methods for the same lifecycle event
******************************************************************************/
package org.eclipse.persistence.internal.jpa.metadata.listeners;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import java.util.Vector;
import org.eclipse.persistence.descriptors.DescriptorEvent;
import org.eclipse.persistence.descriptors.DescriptorEventAdapter;
import org.eclipse.persistence.descriptors.DescriptorEventManager;
import org.eclipse.persistence.exceptions.ValidationException;
import org.eclipse.persistence.internal.security.PrivilegedAccessHelper;
import org.eclipse.persistence.internal.security.PrivilegedMethodInvoker;
import org.eclipse.persistence.internal.security.PrivilegedNewInstanceFromClass;
import org.eclipse.persistence.internal.sessions.AbstractSession;
import org.eclipse.persistence.logging.SessionLog;
/**
* An EntityListener is placed on the owning entity's descriptor.
* Callback methods from an EntityListener require a signature on the method.
* Namely, they must have an Object parameter.
*
* @author Guy Pelletier
* @since Eclipselink 1.0
*/
public class EntityListener<T> extends DescriptorEventAdapter {
public final static String POST_BUILD = "postBuild";
public final static String POST_CLONE = "postClone";
public final static String POST_DELETE = "postDelete";
public final static String POST_INSERT = "postInsert";
public final static String POST_REFRESH = "postRefresh";
public final static String POST_UPDATE = "postUpdate";
public final static String PRE_PERSIST = "prePersist";
public final static String PRE_REMOVE = "preRemove";
public final static String PRE_UPDATE_WITH_CHANGES = "preUpdateWithChanges";
private T m_listener;
private Class<T> m_listenerClass;
private Class m_entityClass;
private Hashtable<String, List<Method>> m_methods;
private Hashtable<String, Hashtable<Integer, Boolean>> m_overriddenEvents;
private static final Map<Integer, String> m_eventStrings;
private AbstractSession owningSession;
static {
// For quick look up of equivalent event strings from event codes.
Map<Integer, String> mappings = new HashMap<>(9);
mappings.put(DescriptorEventManager.PostBuildEvent, POST_BUILD);
mappings.put(DescriptorEventManager.PostCloneEvent, POST_CLONE);
mappings.put(DescriptorEventManager.PostDeleteEvent, POST_DELETE);
mappings.put(DescriptorEventManager.PostInsertEvent, POST_INSERT);
mappings.put(DescriptorEventManager.PostRefreshEvent, POST_REFRESH);
mappings.put(DescriptorEventManager.PostUpdateEvent, POST_UPDATE);
mappings.put(DescriptorEventManager.PrePersistEvent, PRE_PERSIST);
mappings.put(DescriptorEventManager.PreRemoveEvent, PRE_REMOVE);
mappings.put(DescriptorEventManager.PreUpdateWithChangesEvent, PRE_UPDATE_WITH_CHANGES);
m_eventStrings = Collections.unmodifiableMap(mappings);
}
/**
* INTERNAL:
*/
protected EntityListener(Class entityClass) {
m_entityClass = entityClass;
m_methods = new Hashtable<>();
// Remember which events are overridden in subclasses. Overridden events
// must be built for each subclass chain.
m_overriddenEvents = new Hashtable<>();
}
public EntityListener(Class<T> listenerClass, Class entityClass){
this(entityClass);
this.m_listenerClass = listenerClass;
}
/**
* INTERNAL:
* You can have multiple event methods for the same event, however, only
* one event method per class is permitted.
*/
public void addEventMethod(String event, Method method) {
if (m_methods.containsKey(event)) {
Method lastEventMethod = getLastEventMethod(event);
if (lastEventMethod.getDeclaringClass().equals(method.getDeclaringClass())) {
throw ValidationException.multipleLifecycleCallbackMethodsForSameLifecycleEvent(getListenerClass(), method, lastEventMethod);
} else {
// We must be adding a callback method from a mapped superclass
// at this point, so validate the method and add it.
validateMethod(method);
m_methods.get(event).add(method);
}
} else {
// Validate the method is valid.
validateMethod(method);
// Create the methods list and add this method to it.
List<Method> methods = new ArrayList<>();
methods.add(method);
m_methods.put(event, methods);
}
}
/**
* Create the wrapped listener and trigger CDI injection.
* @param entityListenerClass the {@link EntityListener} class
* @return the class instance that has had injection run on it. If injection fails, null.
*/
protected T createEntityListenerAndInjectDependencies(Class<T> entityListenerClass){
try{
return owningSession.<T>getInjectionManager().createManagedBeanAndInjectDependencies(entityListenerClass);
} catch (Exception e){
owningSession.logThrowable(SessionLog.FINEST, SessionLog.JPA, e);
}
return null;
}
/**
* Construct an instance of the wrapped entity listener
* This method will attempt to create the listener in a CDI injection
* friendly manner and if that fails, reflectively instantiate the class
* @return the entity listener instance
*/
protected T constructListenerInstance(){
T entityListenerClassInstance = createEntityListenerAndInjectDependencies(m_listenerClass);
try {
if (PrivilegedAccessHelper.shouldUsePrivilegedAccess()){
try {
if (entityListenerClassInstance == null){
entityListenerClassInstance = AccessController.doPrivileged(new PrivilegedNewInstanceFromClass<>(m_listenerClass));
}
} catch (PrivilegedActionException exception) {
throw ValidationException.errorInstantiatingClass(m_listenerClass, exception.getException());
}
} else {
if (entityListenerClassInstance == null){
entityListenerClassInstance = PrivilegedAccessHelper.newInstanceFromClass(m_listenerClass);
}
}
} catch (IllegalAccessException | InstantiationException exception) {
throw ValidationException.errorInstantiatingClass(m_listenerClass, exception);
}
return entityListenerClassInstance;
}
/**
* INTERNAL:
*/
public Class getEntityClass() {
return m_entityClass;
}
/**
* INTERNAL:
*/
public Hashtable<String, List<Method>> getAllEventMethods() {
return m_methods;
}
/**
* INTERNAL:
*/
public void setAllEventMethods(Hashtable<String, List<Method>> methods) {
m_methods = methods;
}
/**
* INTERNAL:
*/
public void setOwningSession(AbstractSession owningSession) {
this.owningSession = owningSession;
}
/**
* INTERNAL:
*/
protected List<Method> getEventMethods(int eventCode) {
String eventString = m_eventStrings.get(eventCode);
if (eventString != null) {
return getEventMethods(eventString);
} else {
return null;
}
}
/**
* INTERNAL:
*/
protected List<Method> getEventMethods(String event) {
return m_methods.get(event);
}
/**
* INTERNAL:
* Assumes a check for event methods for the given event has been called
* beforehand.
*/
protected Method getLastEventMethod(String event) {
List<Method> methods = m_methods.get(event);
return methods.get(methods.size()-1);
}
public T getListener() {
if (m_listener == null){
m_listener = constructListenerInstance();
}
return m_listener;
}
/**
* INTERNAL:
*/
public Class getListenerClass() {
return m_listenerClass;
}
/**
* INTERNAL:
*/
public AbstractSession getOwningSession() {
return owningSession;
}
/**
* INTERNAL:
*/
public boolean hasCallbackMethods() {
return m_methods.size() > 0;
}
/**
* INTERNAL:
*/
protected boolean hasEventMethods(int eventCode) {
return getEventMethods(eventCode) != null;
}
/**
* INTERNAL:
*/
protected boolean hasEventMethods(String event) {
return getEventMethods(event) != null;
}
/**
* INTERNAL:
*/
protected boolean hasOverriddenEventMethod(List<Method> eventMethods, Method eventMethod) {
if (eventMethods != null) {
for (Method method : eventMethods) {
if (method.getName().equals(eventMethod.getName())) {
return true;
}
}
}
return false;
}
/**
* INTERNAL:
*/
protected boolean hasOverriddenEventMethod(Method eventMethod, int eventCode) {
return hasOverriddenEventMethod(getEventMethods(eventCode), eventMethod);
}
/**
* INTERNAL:
*/
protected boolean hasOverriddenEventMethod(Method eventMethod, String eventCode) {
return hasOverriddenEventMethod(getEventMethods(eventCode), eventMethod);
}
/**
* INTERNAL:
*/
void invokeMethod(Method method, Object onObject, Object[] objectList) {
if (method != null) {
try {
if (PrivilegedAccessHelper.shouldUsePrivilegedAccess()){
try {
AccessController.doPrivileged(new PrivilegedMethodInvoker(method, onObject, objectList));
} catch (PrivilegedActionException exception) {
Exception throwableException = exception.getException();
if (throwableException instanceof IllegalAccessException) {
throw ValidationException.invalidCallbackMethod(onObject.getClass(), method.toString());
} else {
Throwable cause = throwableException.getCause();
if (cause instanceof RuntimeException) {
throw (RuntimeException) cause;
} else {
throw (Error) cause;
}
}
}
} else {
PrivilegedAccessHelper.invokeMethod(method, onObject, objectList);
}
} catch (IllegalAccessException exception) {
throw ValidationException.invalidCallbackMethod(onObject.getClass(), method.toString());
} catch (InvocationTargetException e) {
Throwable cause = e.getCause();
if (cause instanceof RuntimeException) {
throw (RuntimeException) cause;
} else {
throw (Error) cause;
}
}
}
}
/**
* INTERNAL:
*/
void invokeMethod(String event, DescriptorEvent descriptorEvent) {
List<Method> eventMethods = getEventMethods(event);
if (eventMethods != null) {
for (Method method : eventMethods) {
Object[] objectList = { descriptorEvent.getSource() };
invokeMethod(method, getListener(), objectList);
}
}
}
/**
* INTERNAL:
* Return true if listener has a lifecycle callback method that is
* overridden in a subclass.
*/
@Override
public boolean isOverriddenEvent(DescriptorEvent event, Vector<DescriptorEventManager> eventManagers) {
int eventCode = event.getEventCode();
String forSubclass = event.getDescriptor().getJavaClassName();
Hashtable<Integer, Boolean> subClassMap = m_overriddenEvents.get(forSubclass);
// If we haven't built an overridden events map for this subclass, do so now.
if (subClassMap == null) {
subClassMap = new Hashtable<>();
}
// Now check the individual events for this subclass.
if (! subClassMap.containsKey(eventCode)) {
boolean hasOverrides = false;
if (hasEventMethods(eventCode)) {
List<Method> eventMethods = getEventMethods(eventCode);
for (Method eventMethod : eventMethods) {
for (DescriptorEventManager eventManager : eventManagers) {
EntityListener childListener = (EntityListener) eventManager.getEntityEventListener();
// We can't override ourselves ...
if (childListener == this) {
break;
} else {
if (childListener.hasOverriddenEventMethod(eventMethod, eventCode)) {
hasOverrides = true;
break;
}
}
}
if (hasOverrides){
break;
}
}
}
subClassMap.put(eventCode, hasOverrides);
//putting this here prevents a vm reorder from putting an unbuilt Map in the
//m_overriddenEvents collection
m_overriddenEvents.put(forSubclass, subClassMap);
}
return subClassMap.get(eventCode);
}
/**
* INTERNAL:
*/
@Override
public void postBuild(DescriptorEvent event) {
invokeMethod(POST_BUILD, event);
}
/**
* INTERNAL:
*/
@Override
public void postClone(DescriptorEvent event) {
invokeMethod(POST_CLONE, event);
}
/**
* INTERNAL:
*/
@Override
public void postDelete(DescriptorEvent event) {
invokeMethod(POST_DELETE, event);
}
/**
* INTERNAL:
*/
@Override
public void postInsert(DescriptorEvent event) {
invokeMethod(POST_INSERT, event);
}
/**
* INTERNAL:
*/
@Override
public void postRefresh(DescriptorEvent event) {
invokeMethod(POST_REFRESH, event);
}
/**
* INTERNAL:
*/
@Override
public void postUpdate(DescriptorEvent event) {
invokeMethod(POST_UPDATE, event);
}
/**
* INTERNAL:
*/
@Override
public void prePersist(DescriptorEvent event) {
invokeMethod(PRE_PERSIST, event);
}
/**
* INTERNAL:
*/
@Override
public void preRemove(DescriptorEvent event) {
invokeMethod(PRE_REMOVE, event);
}
/**
* INTERNAL:
*/
@Override
public void preUpdateWithChanges(DescriptorEvent event) {
invokeMethod(PRE_UPDATE_WITH_CHANGES, event);
}
/**
* INTERNAL:
*/
public void setPostBuildMethod(Method method) {
addEventMethod(POST_BUILD, method);
}
/**
* INTERNAL:
*/
public void setPostCloneMethod(Method method) {
addEventMethod(POST_CLONE, method);
}
/**
* INTERNAL:
*/
public void setPostDeleteMethod(Method method) {
addEventMethod(POST_DELETE, method);
}
/**
* INTERNAL:
*/
public void setPostInsertMethod(Method method) {
addEventMethod(POST_INSERT, method);
}
/**
* INTERNAL:
*/
public void setPostRefreshMethod(Method method) {
addEventMethod(POST_REFRESH, method);
}
/**
* INTERNAL:
*/
public void setPostUpdateMethod(Method method) {
addEventMethod(POST_UPDATE, method);
}
/**
* INTERNAL:
*/
public void setPrePersistMethod(Method method) {
addEventMethod(PRE_PERSIST, method);
}
/**
* INTERNAL:
*/
public void setPreRemoveMethod(Method method) {
addEventMethod(PRE_REMOVE, method);
}
/**
* INTERNAL:
*/
public void setPreUpdateWithChangesMethod(Method method) {
addEventMethod(PRE_UPDATE_WITH_CHANGES, method);
}
/**
* INTERNAL:
* Used in the debugger.
*/
@Override
public String toString() {
return getEntityClass().getName();
}
/**
* INTERNAL:
*/
protected void validateMethod(Method method) {
int numberOfParameters = method.getParameterTypes().length;
if (numberOfParameters == 1 && method.getParameterTypes()[0].isAssignableFrom(m_entityClass)) {
// So far so good, now check the method modifiers.
validateMethodModifiers(method);
} else {
Class parameterClass = (numberOfParameters == 0) ? null : method.getParameterTypes()[0];
throw ValidationException.invalidEntityListenerCallbackMethodArguments(m_entityClass, parameterClass, getListenerClass(), method.getName());
}
}
/**
* INTERNAL:
*/
protected void validateMethodModifiers(Method method) {
int modifiers = method.getModifiers();
if (Modifier.isStatic(modifiers) || Modifier.isFinal(modifiers)) {
throw ValidationException.invalidCallbackMethodModifier(getListenerClass(), method.getName());
}
}
}