| 1 | /* |
| 2 | * Copyright 2006-2007 the original author or authors. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package org.springframework.batch.retry.interceptor; |
| 18 | |
| 19 | import org.aopalliance.intercept.MethodInterceptor; |
| 20 | import org.aopalliance.intercept.MethodInvocation; |
| 21 | import org.springframework.aop.ProxyMethodInvocation; |
| 22 | import org.springframework.batch.retry.RetryCallback; |
| 23 | import org.springframework.batch.retry.RetryContext; |
| 24 | import org.springframework.batch.retry.RetryOperations; |
| 25 | import org.springframework.batch.retry.support.RetryTemplate; |
| 26 | import org.springframework.util.Assert; |
| 27 | |
| 28 | /** |
| 29 | * A {@link MethodInterceptor} that can be used to automatically retry calls to |
| 30 | * a method on a service if it fails. The injected {@link RetryOperations} is |
| 31 | * used to control the number of retries. By default it will retry a fixed |
| 32 | * number of times, according to the defaults in {@link RetryTemplate}.<br/> |
| 33 | * |
| 34 | * Hint about transaction boundaries. If you want to retry a failed transaction |
| 35 | * you need to make sure that the transaction boundary is inside the retry, |
| 36 | * otherwise the successful attempt will roll back with the whole transaction. |
| 37 | * If the method being intercepted is also transactional, then use the ordering |
| 38 | * hints in the advice declarations to ensure that this one is before the |
| 39 | * transaction interceptor in the advice chain. |
| 40 | * |
| 41 | * @author Rob Harrop |
| 42 | * @author Dave Syer |
| 43 | */ |
| 44 | public class RetryOperationsInterceptor implements MethodInterceptor { |
| 45 | |
| 46 | private RetryOperations retryOperations = new RetryTemplate(); |
| 47 | |
| 48 | public void setRetryTemplate(RetryOperations retryTemplate) { |
| 49 | Assert.notNull(retryTemplate, "'retryOperations' cannot be null."); |
| 50 | this.retryOperations = retryTemplate; |
| 51 | } |
| 52 | |
| 53 | public Object invoke(final MethodInvocation invocation) throws Throwable { |
| 54 | |
| 55 | return this.retryOperations.execute(new RetryCallback() { |
| 56 | |
| 57 | public Object doWithRetry(RetryContext context) throws Throwable { |
| 58 | |
| 59 | /* |
| 60 | * If we don't copy the invocation carefully it won't keep a |
| 61 | * reference to the other interceptors in the chain. We don't |
| 62 | * have a choice here but to specialise to |
| 63 | * ReflectiveMethodInvocation (but how often would another |
| 64 | * implementation come along?). |
| 65 | */ |
| 66 | if (invocation instanceof ProxyMethodInvocation) { |
| 67 | return ((ProxyMethodInvocation) invocation) |
| 68 | .invocableClone().proceed(); |
| 69 | } else { |
| 70 | throw new IllegalStateException( |
| 71 | "MethodInvocation of the wrong type detected - this should not happen with Spring AOP, so please raise an issue if you see this exception"); |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | }); |
| 76 | } |
| 77 | } |