| /******************************************************************************* |
| * Copyright (c) 2008, 2009 Oracle. All rights reserved. |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v1.0, which accompanies this distribution |
| * and is available at http://www.eclipse.org/legal/epl-v10.html. |
| * |
| * Contributors: |
| * Oracle - initial API and implementation |
| ******************************************************************************/ |
| package org.eclipse.jpt.utility.internal; |
| |
| import java.io.Serializable; |
| |
| /** |
| * Simple interface for allowing clients to pass an exception handler to a |
| * service (e.g. to log the exception). This is particularly helpful if the |
| * service executes on another, possibly inaccessible, thread. |
| * <p> |
| * Provisional API: This interface is part of an interim API that is still |
| * under development and expected to change significantly before reaching |
| * stability. It is available at this early stage to solicit feedback from |
| * pioneering adopters on the understanding that any code that uses this API |
| * will almost certainly be broken (repeatedly) as the API evolves. |
| */ |
| public interface ExceptionHandler { |
| |
| /** |
| * The specified exception was thrown. Handle it appropriately. |
| */ |
| void handleException(Throwable t); |
| |
| /** |
| * Singleton implementation of the exception handler interface that does |
| * nothing with the exception. |
| */ |
| final class Null implements ExceptionHandler, Serializable { |
| public static final ExceptionHandler INSTANCE = new Null(); |
| public static ExceptionHandler instance() { |
| return INSTANCE; |
| } |
| // ensure single instance |
| private Null() { |
| super(); |
| } |
| public void handleException(Throwable t) { |
| // do nothing |
| } |
| @Override |
| public String toString() { |
| return "ExceptionHandler.Null"; //$NON-NLS-1$ |
| } |
| private static final long serialVersionUID = 1L; |
| private Object readResolve() { |
| // replace this object with the singleton |
| return INSTANCE; |
| } |
| } |
| |
| /** |
| * Singleton implementation of the exception handler interface that |
| * wraps the exception in a runtime exception and throws it. |
| */ |
| final class Runtime implements ExceptionHandler, Serializable { |
| public static final ExceptionHandler INSTANCE = new Runtime(); |
| public static ExceptionHandler instance() { |
| return INSTANCE; |
| } |
| // ensure single instance |
| private Runtime() { |
| super(); |
| } |
| public void handleException(Throwable t) { |
| // re-throw the exception unchecked |
| throw new RuntimeException(t); |
| } |
| @Override |
| public String toString() { |
| return "ExceptionHandler.Runtime"; //$NON-NLS-1$ |
| } |
| private static final long serialVersionUID = 1L; |
| private Object readResolve() { |
| // replace this object with the singleton |
| return INSTANCE; |
| } |
| } |
| |
| } |