| /** |
| * 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.yarn.ipc; |
| |
| import java.io.IOException; |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.InvocationTargetException; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.ipc.RemoteException; |
| import org.apache.hadoop.yarn.exceptions.YarnException; |
| |
| import com.google.protobuf.ServiceException; |
| |
| @InterfaceAudience.LimitedPrivate({ "MapReduce", "YARN" }) |
| public class RPCUtil { |
| |
| /** |
| * Returns an instance of {@link YarnException} |
| */ |
| public static YarnException getRemoteException(Throwable t) { |
| return new YarnException(t); |
| } |
| |
| /** |
| * Returns an instance of {@link YarnException} |
| */ |
| public static YarnException getRemoteException(String message) { |
| return new YarnException(message); |
| } |
| |
| private static <T extends Throwable> T instantiateException( |
| Class<? extends T> cls, RemoteException re) throws RemoteException { |
| try { |
| Constructor<? extends T> cn = cls.getConstructor(String.class); |
| cn.setAccessible(true); |
| T ex = cn.newInstance(re.getMessage()); |
| ex.initCause(re); |
| return ex; |
| // RemoteException contains useful information as against the |
| // java.lang.reflect exceptions. |
| } catch (NoSuchMethodException e) { |
| throw re; |
| } catch (IllegalArgumentException e) { |
| throw re; |
| } catch (SecurityException e) { |
| throw re; |
| } catch (InstantiationException e) { |
| throw re; |
| } catch (IllegalAccessException e) { |
| throw re; |
| } catch (InvocationTargetException e) { |
| throw re; |
| } |
| } |
| |
| private static <T extends YarnException> T instantiateYarnException( |
| Class<? extends T> cls, RemoteException re) throws RemoteException { |
| return instantiateException(cls, re); |
| } |
| |
| private static <T extends IOException> T instantiateIOException( |
| Class<? extends T> cls, RemoteException re) throws RemoteException { |
| return instantiateException(cls, re); |
| } |
| |
| private static <T extends RuntimeException> T instantiateRuntimeException( |
| Class<? extends T> cls, RemoteException re) throws RemoteException { |
| return instantiateException(cls, re); |
| } |
| |
| /** |
| * Utility method that unwraps and returns appropriate exceptions. |
| * |
| * @param se |
| * ServiceException |
| * @return An instance of the actual exception, which will be a subclass of |
| * {@link YarnException} or {@link IOException} |
| */ |
| public static Void unwrapAndThrowException(ServiceException se) |
| throws IOException, YarnException { |
| Throwable cause = se.getCause(); |
| if (cause == null) { |
| // SE generated by the RPC layer itself. |
| throw new IOException(se); |
| } else { |
| if (cause instanceof RemoteException) { |
| RemoteException re = (RemoteException) cause; |
| Class<?> realClass = null; |
| try { |
| realClass = Class.forName(re.getClassName()); |
| } catch (ClassNotFoundException cnf) { |
| // Assume this to be a new exception type added to YARN. This isn't |
| // absolutely correct since the RPC layer could add an exception as |
| // well. |
| throw instantiateYarnException(YarnException.class, re); |
| } |
| |
| if (YarnException.class.isAssignableFrom(realClass)) { |
| throw instantiateYarnException( |
| realClass.asSubclass(YarnException.class), re); |
| } else if (IOException.class.isAssignableFrom(realClass)) { |
| throw instantiateIOException(realClass.asSubclass(IOException.class), |
| re); |
| } else if (RuntimeException.class.isAssignableFrom(realClass)) { |
| throw instantiateRuntimeException( |
| realClass.asSubclass(RuntimeException.class), re); |
| } else { |
| throw re; |
| } |
| // RemoteException contains useful information as against the |
| // java.lang.reflect exceptions. |
| |
| } else if (cause instanceof IOException) { |
| // RPC Client exception. |
| throw (IOException) cause; |
| } else if (cause instanceof RuntimeException) { |
| // RPC RuntimeException |
| throw (RuntimeException) cause; |
| } else { |
| // Should not be generated. |
| throw new IOException(se); |
| } |
| } |
| } |
| } |