org.springframework.transaction.event.ApplicationListenerMethodTransactionalAdapter.java Source code

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Here is the source code for org.springframework.transaction.event.ApplicationListenerMethodTransactionalAdapter.java

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/*
 * Copyright 2002-2016 the original author or authors.
 *
 * Licensed 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.springframework.transaction.event;

import java.lang.reflect.Method;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.context.ApplicationEvent;
import org.springframework.context.event.ApplicationListenerMethodAdapter;
import org.springframework.context.event.EventListener;
import org.springframework.context.event.GenericApplicationListener;
import org.springframework.core.annotation.AnnotatedElementUtils;
import org.springframework.transaction.support.TransactionSynchronization;
import org.springframework.transaction.support.TransactionSynchronizationAdapter;
import org.springframework.transaction.support.TransactionSynchronizationManager;

/**
 * {@link GenericApplicationListener} adapter that delegates the processing of
 * an event to a {@link TransactionalEventListener} annotated method. Supports
 * the exact same features as any regular {@link EventListener} annotated method
 * but is aware of the transactional context of the event publisher.
 * <p>
 * Processing of {@link TransactionalEventListener} is enabled automatically when
 * Spring's transaction management is enabled. For other cases, registering a
 * bean of type {@link TransactionalEventListenerFactory} is required.
 *
 * @author Stephane Nicoll
 * @since 4.2
 * @see ApplicationListenerMethodAdapter
 * @see TransactionalEventListener
 */
class ApplicationListenerMethodTransactionalAdapter extends ApplicationListenerMethodAdapter {

    protected final Log logger = LogFactory.getLog(getClass());

    private final TransactionalEventListener annotation;

    public ApplicationListenerMethodTransactionalAdapter(String beanName, Class<?> targetClass, Method method) {
        super(beanName, targetClass, method);
        this.annotation = AnnotatedElementUtils.findMergedAnnotation(method, TransactionalEventListener.class);
        if (this.annotation == null) {
            throw new IllegalStateException("No TransactionalEventListener annotation found on '" + method + "'");
        }
    }

    @Override
    public void onApplicationEvent(ApplicationEvent event) {
        if (TransactionSynchronizationManager.isSynchronizationActive()) {
            TransactionSynchronization transactionSynchronization = createTransactionSynchronization(event);
            TransactionSynchronizationManager.registerSynchronization(transactionSynchronization);
        } else if (this.annotation.fallbackExecution()) {
            if (this.annotation.phase() == TransactionPhase.AFTER_ROLLBACK) {
                logger.warn("Processing '" + event + "' as a fallback execution on AFTER_ROLLBACK phase.");
            }
            processEvent(event);
        } else {
            if (logger.isDebugEnabled()) {
                logger.debug("No transaction is running, skipping '" + event + "' for '" + this + "'");
            }
        }
    }

    private TransactionSynchronization createTransactionSynchronization(ApplicationEvent event) {
        return new TransactionSynchronizationEventAdapter(this, event, this.annotation.phase());
    }

    private static class TransactionSynchronizationEventAdapter extends TransactionSynchronizationAdapter {

        private final ApplicationListenerMethodAdapter listener;

        private final ApplicationEvent event;

        private final TransactionPhase phase;

        public TransactionSynchronizationEventAdapter(ApplicationListenerMethodAdapter listener,
                ApplicationEvent event, TransactionPhase phase) {

            this.listener = listener;
            this.event = event;
            this.phase = phase;
        }

        @Override
        public void beforeCommit(boolean readOnly) {
            if (this.phase == TransactionPhase.BEFORE_COMMIT) {
                processEvent();
            }
        }

        @Override
        public void afterCompletion(int status) {
            if (this.phase == TransactionPhase.AFTER_COMPLETION) {
                processEvent();
            } else if (this.phase == TransactionPhase.AFTER_COMMIT && status == STATUS_COMMITTED) {
                processEvent();
            } else if (this.phase == TransactionPhase.AFTER_ROLLBACK && status == STATUS_ROLLED_BACK) {
                processEvent();
            }
        }

        @Override
        public int getOrder() {
            return this.listener.getOrder();
        }

        protected void processEvent() {
            this.listener.processEvent(this.event);
        }
    }

}