| /* |
| * Copyright (C) 2010 The Guava Authors |
| * |
| * Licensed 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 com.google.common.util.concurrent; |
| |
| import static java.util.logging.Level.SEVERE; |
| |
| import com.google.common.annotations.GwtIncompatible; |
| import com.google.common.annotations.VisibleForTesting; |
| import java.lang.Thread.UncaughtExceptionHandler; |
| import java.util.Locale; |
| import java.util.logging.Logger; |
| |
| /** |
| * Factories for {@link UncaughtExceptionHandler} instances. |
| * |
| * @author Gregory Kick |
| * @since 8.0 |
| */ |
| @GwtIncompatible |
| public final class UncaughtExceptionHandlers { |
| private UncaughtExceptionHandlers() {} |
| |
| /** |
| * Returns an exception handler that exits the system. This is particularly useful for the main |
| * thread, which may start up other, non-daemon threads, but fail to fully initialize the |
| * application successfully. |
| * |
| * <p>Example usage: |
| * |
| * <pre> |
| * public static void main(String[] args) { |
| * Thread.currentThread().setUncaughtExceptionHandler(UncaughtExceptionHandlers.systemExit()); |
| * ... |
| * </pre> |
| * |
| * <p>The returned handler logs any exception at severity {@code SEVERE} and then shuts down the |
| * process with an exit status of 1, indicating abnormal termination. |
| */ |
| public static UncaughtExceptionHandler systemExit() { |
| return new Exiter(Runtime.getRuntime()); |
| } |
| |
| @VisibleForTesting |
| static final class Exiter implements UncaughtExceptionHandler { |
| private static final Logger logger = Logger.getLogger(Exiter.class.getName()); |
| |
| private final Runtime runtime; |
| |
| Exiter(Runtime runtime) { |
| this.runtime = runtime; |
| } |
| |
| @Override |
| public void uncaughtException(Thread t, Throwable e) { |
| try { |
| // cannot use FormattingLogger due to a dependency loop |
| logger.log( |
| SEVERE, String.format(Locale.ROOT, "Caught an exception in %s. Shutting down.", t), e); |
| } catch (Throwable errorInLogging) { |
| // If logging fails, e.g. due to missing memory, at least try to log the |
| // message and the cause for the failed logging. |
| System.err.println(e.getMessage()); |
| System.err.println(errorInLogging.getMessage()); |
| } finally { |
| runtime.exit(1); |
| } |
| } |
| } |
| } |