| 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.policy; |
| 18 | |
| 19 | import java.util.ArrayList; |
| 20 | import java.util.Arrays; |
| 21 | import java.util.List; |
| 22 | |
| 23 | import org.springframework.batch.retry.RetryContext; |
| 24 | import org.springframework.batch.retry.RetryPolicy; |
| 25 | import org.springframework.batch.retry.context.RetryContextSupport; |
| 26 | |
| 27 | /** |
| 28 | * A {@link RetryPolicy} that composes a list of other policies and delegates |
| 29 | * calls to them in order. |
| 30 | * |
| 31 | * @author Dave Syer |
| 32 | * |
| 33 | */ |
| 34 | public class CompositeRetryPolicy implements RetryPolicy { |
| 35 | |
| 36 | RetryPolicy[] policies = new RetryPolicy[0]; |
| 37 | |
| 38 | /** |
| 39 | * Setter for policies. |
| 40 | * |
| 41 | * @param policies |
| 42 | */ |
| 43 | public void setPolicies(RetryPolicy[] policies) { |
| 44 | this.policies = Arrays.asList(policies).toArray(new RetryPolicy[policies.length]); |
| 45 | } |
| 46 | |
| 47 | /** |
| 48 | * Delegate to the policies that were in operation when the context was |
| 49 | * created. If any of them cannot retry then return false, oetherwise return |
| 50 | * true. |
| 51 | * |
| 52 | * @see org.springframework.batch.retry.RetryPolicy#canRetry(org.springframework.batch.retry.RetryContext) |
| 53 | */ |
| 54 | public boolean canRetry(RetryContext context) { |
| 55 | RetryContext[] contexts = ((CompositeRetryContext) context).contexts; |
| 56 | RetryPolicy[] policies = ((CompositeRetryContext) context).policies; |
| 57 | for (int i = 0; i < contexts.length; i++) { |
| 58 | if (!policies[i].canRetry(contexts[i])) { |
| 59 | return false; |
| 60 | } |
| 61 | } |
| 62 | return true; |
| 63 | } |
| 64 | |
| 65 | /** |
| 66 | * Delegate to the policies that were in operation when the context was |
| 67 | * created. If any of them fails to close the exception is propagated (and |
| 68 | * those later in the chain are closed before re-throwing). |
| 69 | * |
| 70 | * @see org.springframework.batch.retry.RetryPolicy#close(org.springframework.batch.retry.RetryContext) |
| 71 | */ |
| 72 | public void close(RetryContext context) { |
| 73 | RetryContext[] contexts = ((CompositeRetryContext) context).contexts; |
| 74 | RetryPolicy[] policies = ((CompositeRetryContext) context).policies; |
| 75 | RuntimeException exception = null; |
| 76 | for (int i = 0; i < contexts.length; i++) { |
| 77 | try { |
| 78 | policies[i].close(contexts[i]); |
| 79 | } |
| 80 | catch (RuntimeException e) { |
| 81 | if (exception == null) { |
| 82 | exception = e; |
| 83 | } |
| 84 | } |
| 85 | } |
| 86 | if (exception != null) { |
| 87 | throw exception; |
| 88 | } |
| 89 | } |
| 90 | |
| 91 | /** |
| 92 | * Creates a new context that copies the existing policies and keeps a list |
| 93 | * of the contexts from each one. |
| 94 | * |
| 95 | * @see org.springframework.batch.retry.RetryPolicy#open(RetryContext) |
| 96 | */ |
| 97 | public RetryContext open(RetryContext parent) { |
| 98 | List<RetryContext> list = new ArrayList<RetryContext>(); |
| 99 | for (int i = 0; i < policies.length; i++) { |
| 100 | list.add(policies[i].open(parent)); |
| 101 | } |
| 102 | return new CompositeRetryContext(parent, list); |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * Delegate to the policies that were in operation when the context was |
| 107 | * created. |
| 108 | * |
| 109 | * @see org.springframework.batch.retry.RetryPolicy#close(org.springframework.batch.retry.RetryContext) |
| 110 | */ |
| 111 | public void registerThrowable(RetryContext context, Throwable throwable) { |
| 112 | RetryContext[] contexts = ((CompositeRetryContext) context).contexts; |
| 113 | RetryPolicy[] policies = ((CompositeRetryContext) context).policies; |
| 114 | for (int i = 0; i < contexts.length; i++) { |
| 115 | policies[i].registerThrowable(contexts[i], throwable); |
| 116 | } |
| 117 | ((RetryContextSupport) context).registerThrowable(throwable); |
| 118 | } |
| 119 | |
| 120 | private class CompositeRetryContext extends RetryContextSupport { |
| 121 | RetryContext[] contexts; |
| 122 | |
| 123 | RetryPolicy[] policies; |
| 124 | |
| 125 | public CompositeRetryContext(RetryContext parent, List<RetryContext> contexts) { |
| 126 | super(parent); |
| 127 | this.contexts = contexts.toArray(new RetryContext[0]); |
| 128 | this.policies = CompositeRetryPolicy.this.policies; |
| 129 | } |
| 130 | |
| 131 | } |
| 132 | |
| 133 | } |