| /** |
| * 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.oozie; |
| |
| import org.apache.oozie.util.XLog; |
| |
| /** |
| * Fault Injection support class. <p> Concrete classes should be available only during testing, not in production. <p> |
| * To activate fault injection the {@link #FAULT_INJECTION} system property must be set to true. <p> When fault |
| * injection is activated, the concrete class (specified by name) will be call for activation. <p> Concrete classes |
| * should be activated by presense of a second system property. <p> This fault injection pattern provides 3 levels of |
| * safeguard: a general 'fault injection' system property, the availabity of of the concrete 'fault injection' class in |
| * the classpath, a specifi 'fault injection' system property. <p> Refer to the <code>SkipCommitFaultInjection</code> |
| * class in the test classes for an example. |
| */ |
| public abstract class FaultInjection { |
| |
| public static final String FAULT_INJECTION = "oozie.fault.injection"; |
| |
| private static FaultInjection getFaultInjection(String className) { |
| if (Boolean.parseBoolean(System.getProperty(FAULT_INJECTION, "false"))) { |
| try { |
| Class klass = Thread.currentThread().getContextClassLoader().loadClass(className); |
| return (FaultInjection) klass.newInstance(); |
| } |
| catch (ClassNotFoundException ex) { |
| XLog.getLog(FaultInjection.class).warn("Trying to activate fault injection in production", ex); |
| } |
| catch (IllegalAccessException ex) { |
| throw new RuntimeException(XLog.format("Could not initialize [{0}]", className, ex), ex); |
| } |
| catch (InstantiationException ex) { |
| throw new RuntimeException(XLog.format("Could not initialize [{0}]", className, ex), ex); |
| } |
| } |
| return null; |
| } |
| |
| public static boolean activate(String className) { |
| FaultInjection fi = getFaultInjection(className); |
| if (fi != null) { |
| className = className.substring(className.lastIndexOf(".") + 1); |
| if (fi.activate()) { |
| XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, ACTIVATING [{0}]", className); |
| return true; |
| } |
| else { |
| XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, DID NOT ACTIVATE [{0}]", className); |
| } |
| } |
| return false; |
| } |
| |
| public static void deactivate(String className) { |
| FaultInjection fi = getFaultInjection(className); |
| if (fi != null) { |
| className = className.substring(className.lastIndexOf(".") + 1); |
| if (fi.isActive()) { |
| XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, DEACTIVATING [{0}]", className); |
| fi.deactivate(); |
| } |
| else { |
| XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, CANNOT DEACTIVATE, NOT ACTIVE [{0}]", |
| className); |
| } |
| } |
| } |
| |
| public static boolean isActive(String className) { |
| FaultInjection fi = getFaultInjection(className); |
| if (fi != null) { |
| className = className.substring(className.lastIndexOf(".") + 1); |
| if (fi.isActive()) { |
| XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, ACTIVE [{0}]", className); |
| return true; |
| } |
| else { |
| XLog.getLog(FaultInjection.class).warn("FAULT INJECTION, NOT ACTIVE [{0}]", className); |
| } |
| } |
| return false; |
| } |
| |
| public abstract boolean activate(); |
| |
| public abstract void deactivate(); |
| |
| public abstract boolean isActive(); |
| |
| } |