| /** |
| * 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.io.retry; |
| |
| import java.io.IOException; |
| |
| import org.apache.hadoop.ipc.RemoteException; |
| import org.apache.hadoop.ipc.StandbyException; |
| |
| public class UnreliableImplementation implements UnreliableInterface { |
| |
| private int failsOnceInvocationCount, |
| failsOnceWithValueInvocationCount, |
| failsTenTimesInvocationCount, |
| succeedsOnceThenFailsCount, |
| succeedsOnceThenFailsIdempotentCount, |
| succeedsTenTimesThenFailsCount; |
| |
| private String identifier; |
| private TypeOfExceptionToFailWith exceptionToFailWith; |
| |
| public static enum TypeOfExceptionToFailWith { |
| UNRELIABLE_EXCEPTION, |
| STANDBY_EXCEPTION, |
| IO_EXCEPTION, |
| REMOTE_EXCEPTION |
| } |
| |
| public UnreliableImplementation() { |
| this(null); |
| } |
| |
| public UnreliableImplementation(String identifier) { |
| this(identifier, TypeOfExceptionToFailWith.UNRELIABLE_EXCEPTION); |
| } |
| |
| public void setIdentifier(String identifier) { |
| this.identifier = identifier; |
| } |
| |
| public UnreliableImplementation(String identifier, |
| TypeOfExceptionToFailWith exceptionToFailWith) { |
| this.identifier = identifier; |
| this.exceptionToFailWith = exceptionToFailWith; |
| } |
| |
| @Override |
| public void alwaysSucceeds() { |
| // do nothing |
| } |
| |
| @Override |
| public void alwaysFailsWithFatalException() throws FatalException { |
| throw new FatalException(); |
| } |
| |
| @Override |
| public void alwaysFailsWithRemoteFatalException() throws RemoteException { |
| throw new RemoteException(FatalException.class.getName(), "Oops"); |
| } |
| |
| @Override |
| public void failsOnceThenSucceeds() throws UnreliableException { |
| if (failsOnceInvocationCount++ == 0) { |
| throw new UnreliableException(); |
| } |
| } |
| |
| @Override |
| public boolean failsOnceThenSucceedsWithReturnValue() throws UnreliableException { |
| if (failsOnceWithValueInvocationCount++ == 0) { |
| throw new UnreliableException(); |
| } |
| return true; |
| } |
| |
| @Override |
| public void failsTenTimesThenSucceeds() throws UnreliableException { |
| if (failsTenTimesInvocationCount++ < 10) { |
| throw new UnreliableException(); |
| } |
| } |
| |
| @Override |
| public String succeedsOnceThenFailsReturningString() |
| throws UnreliableException, IOException, StandbyException { |
| if (succeedsOnceThenFailsCount++ < 1) { |
| return identifier; |
| } else { |
| throwAppropriateException(exceptionToFailWith, identifier); |
| return null; |
| } |
| } |
| |
| @Override |
| public String succeedsTenTimesThenFailsReturningString() |
| throws UnreliableException, IOException, StandbyException { |
| if (succeedsTenTimesThenFailsCount++ < 10) { |
| return identifier; |
| } else { |
| throwAppropriateException(exceptionToFailWith, identifier); |
| return null; |
| } |
| } |
| |
| @Override |
| public String succeedsOnceThenFailsReturningStringIdempotent() |
| throws UnreliableException, StandbyException, IOException { |
| if (succeedsOnceThenFailsIdempotentCount++ < 1) { |
| return identifier; |
| } else { |
| throwAppropriateException(exceptionToFailWith, identifier); |
| return null; |
| } |
| } |
| |
| @Override |
| public String failsIfIdentifierDoesntMatch(String identifier) |
| throws UnreliableException, StandbyException, IOException { |
| if (this.identifier.equals(identifier)) { |
| return identifier; |
| } else { |
| String message = "expected '" + this.identifier + "' but received '" + |
| identifier + "'"; |
| throwAppropriateException(exceptionToFailWith, message); |
| return null; |
| } |
| } |
| |
| @Override |
| public void nonIdempotentVoidFailsIfIdentifierDoesntMatch(String identifier) |
| throws UnreliableException, StandbyException, IOException { |
| if (this.identifier.equals(identifier)) { |
| return; |
| } else { |
| String message = "expected '" + this.identifier + "' but received '" + |
| identifier + "'"; |
| throwAppropriateException(exceptionToFailWith, message); |
| } |
| } |
| |
| private static void throwAppropriateException(TypeOfExceptionToFailWith eType, |
| String message) throws UnreliableException, StandbyException, IOException { |
| switch (eType) { |
| case STANDBY_EXCEPTION: |
| throw new StandbyException(message); |
| case UNRELIABLE_EXCEPTION: |
| throw new UnreliableException(message); |
| case IO_EXCEPTION: |
| throw new IOException(message); |
| case REMOTE_EXCEPTION: |
| throw new RemoteException(IOException.class.getName(), message); |
| default: |
| throw new RuntimeException(message); |
| } |
| } |
| } |