| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.hadoop.service; |
| |
| import org.apache.hadoop.conf.Configuration; |
| |
| /** |
| * This is a service that can be configured to break on any of the lifecycle |
| * events, so test the failure handling of other parts of the service |
| * infrastructure. |
| * |
| * It retains a counter to the number of times each entry point is called - |
| * these counters are incremented before the exceptions are raised and |
| * before the superclass state methods are invoked. |
| * |
| */ |
| |
| |
| public class BreakableService extends AbstractService { |
| |
| private boolean failOnInit; |
| private boolean failOnStart; |
| private boolean failOnStop; |
| private int[] counts = new int[4]; |
| |
| public BreakableService() { |
| this(false, false, false); |
| } |
| |
| public BreakableService(boolean failOnInit, |
| boolean failOnStart, |
| boolean failOnStop) { |
| super("BreakableService"); |
| this.failOnInit = failOnInit; |
| this.failOnStart = failOnStart; |
| this.failOnStop = failOnStop; |
| inc(STATE.NOTINITED); |
| } |
| |
| private int convert(STATE state) { |
| return state.getValue(); |
| } |
| |
| private void inc(STATE state) { |
| int index = convert(state); |
| counts[index] ++; |
| } |
| |
| public int getCount(STATE state) { |
| return counts[convert(state)]; |
| } |
| |
| private void maybeFail(boolean fail, String action) throws Exception { |
| if (fail) { |
| throw createFailureException(action); |
| } |
| } |
| |
| /** |
| * Override point: create the exception to raise |
| * @param action action in progress |
| * @return the exception that will be thrown |
| */ |
| protected Exception createFailureException(String action) { |
| return new BrokenLifecycleEvent(this, action); |
| } |
| |
| @Override |
| protected void serviceInit(Configuration conf) throws Exception { |
| inc(STATE.INITED); |
| maybeFail(failOnInit, "init"); |
| super.serviceInit(conf); |
| } |
| |
| @Override |
| protected void serviceStart() throws Exception { |
| inc(STATE.STARTED); |
| maybeFail(failOnStart, "start"); |
| } |
| |
| @Override |
| protected void serviceStop() throws Exception { |
| inc(STATE.STOPPED); |
| maybeFail(failOnStop, "stop"); |
| } |
| |
| public void setFailOnInit(boolean failOnInit) { |
| this.failOnInit = failOnInit; |
| } |
| |
| public void setFailOnStart(boolean failOnStart) { |
| this.failOnStart = failOnStart; |
| } |
| |
| public void setFailOnStop(boolean failOnStop) { |
| this.failOnStop = failOnStop; |
| } |
| |
| /** |
| * The exception explicitly raised on a failure. |
| */ |
| public static class BrokenLifecycleEvent extends RuntimeException { |
| |
| public final STATE state; |
| |
| public BrokenLifecycleEvent(Service service, String action) { |
| super("Lifecycle Failure during " + action + " state is " |
| + service.getServiceState()); |
| state = service.getServiceState(); |
| } |
| } |
| } |