/*
* This file is part of LibrePlan
*
* Copyright (C) 2009-2010 Fundación para o Fomento da Calidade Industrial e
* Desenvolvemento Tecnolóxico de Galicia
* Copyright (C) 2010-2011 Igalia, S.L.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.libreplan.web.common.concurrentdetection;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Proxy;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.core.annotation.Order;
import org.springframework.dao.OptimisticLockingFailureException;
/**
* Responsible of handling {@link OptimisticLockingFailureException} on Spring beans
* marked with {@link OnConcurrentModification}.
*
* @author Óscar González Fernández <ogonzalez@igalia.com>
*/
@Aspect
@Order(0)
public class ConcurrentModificationHandling {
public ConcurrentModificationHandling() {
}
public static <T> T addHandling(final String goToPage, Class<T> interfaceKlass, T toBeWrapped) {
Class<?>[] classesToProxy = { interfaceKlass };
Object result =
Proxy.newProxyInstance(interfaceKlass.getClassLoader(), classesToProxy, handler(toBeWrapped, goToPage));
return interfaceKlass.cast(result);
}
private static InvocationHandler handler(final Object toBeWraped, final String goToPage) {
return (proxy, method, args) -> {
try {
return method.invoke(toBeWraped, args);
} catch (InvocationTargetException e) {
Throwable cause = e.getCause();
if ( cause instanceof OptimisticLockingFailureException ) {
OptimisticLockingFailureException optimisticLockingFailureException =
(OptimisticLockingFailureException) cause;
ConcurrentModificationController.showException(optimisticLockingFailureException, goToPage);
}
throw cause;
}
};
}
@SuppressWarnings("unused")
@Pointcut(value = "@within(onConcurrentModification))")
private void methodWithinConcurrentModificationMarkedType(OnConcurrentModification onConcurrentModification) {
}
/**
* It intercepts the calls to public methods of Spring beans marked with {@link OnConcurrentModification}.
*
* When an {@link OptimisticLockingFailureException} happens the page for concurrent
* modification is shown and the user is returned to the page specified by {@link OnConcurrentModification}.
*
* @param jointPoint
* @param onConcurrentModification
* the annotation applied to object's type
* @return the object that would be originally returned
*/
@Around("methodWithinConcurrentModificationMarkedType(onConcurrentModification) && execution(public * * (..))")
public Object whenConcurrentModification(ProceedingJoinPoint jointPoint,
OnConcurrentModification onConcurrentModification) throws Throwable {
try {
return jointPoint.proceed(jointPoint.getArgs());
} catch (OptimisticLockingFailureException e) {
ConcurrentModificationController.showException(e, onConcurrentModification.goToPage());
throw e;
}
}
}