/*
* Copyright 2006-2007 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.retry.support;
import org.springframework.retry.RetryCallback;
import org.springframework.retry.RetryContext;
import org.springframework.retry.RetryOperations;
/**
* Global variable support for retry clients. Normally it is not necessary for
* clients to be aware of the surrounding environment because a
* {@link RetryCallback} can always use the context it is passed by the
* enclosing {@link RetryOperations}. But occasionally it might be helpful to
* have lower level access to the ongoing {@link RetryContext} so we provide a
* global accessor here. The mutator methods ({@link #clear()} and
* {@link #register(RetryContext)} should not be used except internally by
* {@link RetryOperations} implementations.
*
* @author Dave Syer
*
*/
public final class RetrySynchronizationManager {
private RetrySynchronizationManager() {}
private static final ThreadLocal<RetryContext> context = new ThreadLocal<RetryContext>();
/**
* Public accessor for the locally enclosing {@link RetryContext}.
*
* @return the current retry context, or null if there isn't one
*/
public static RetryContext getContext() {
RetryContext result = (RetryContext) context.get();
return result;
}
/**
* Method for registering a context - should only be used by
* {@link RetryOperations} implementations to ensure that
* {@link #getContext()} always returns the correct value.
*
* @param context the new context to register
* @return the old context if there was one
*/
public static RetryContext register(RetryContext context) {
RetryContext oldContext = getContext();
RetrySynchronizationManager.context.set(context);
return oldContext;
}
/**
* Clear the current context at the end of a batch - should only be used by
* {@link RetryOperations} implementations.
*
* @return the old value if there was one.
*/
public static RetryContext clear() {
RetryContext value = getContext();
RetryContext parent = value == null ? null : value.getParent();
RetrySynchronizationManager.context.set(parent);
return value;
}
}