| /******************************************************************************* |
| * Copyright (c) 2008, 2010 VMware Inc. |
| * 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: |
| * VMware Inc. - initial contribution |
| *******************************************************************************/ |
| |
| package org.eclipse.virgo.kernel.serviceability.dump; |
| |
| /** |
| * Maintains state about which {@link Throwable} was last seen for the current thread. |
| * <p /> |
| * |
| * <strong>Concurrent Semantics</strong><br /> |
| * |
| * State is thread local. |
| * |
| */ |
| final class FFDCExceptionState { |
| |
| private static final State STATE = new State(); |
| |
| /** |
| * Record that the supplied {@link Throwable} has been seen. |
| * |
| * @param t the <code>Throwable</code>. |
| */ |
| public static void record(Throwable t) { |
| STATE.set(t); |
| } |
| |
| /** |
| * Query whether the supplied {@link Throwable} or one of its causes has been seen. |
| * |
| * @param t the <code>Throwable</code> |
| * @return <code>true</code> if the <code>Throwable</code> has been seen, otherwise <code>false</code>. |
| */ |
| public static boolean seen(Throwable t) { |
| boolean seen = false; |
| Throwable s = t; |
| do { |
| if (s.equals(STATE.get())) { |
| seen = true; |
| break; |
| } |
| s = s.getCause(); |
| } while (s != null); |
| return seen; |
| } |
| |
| private static class State extends ThreadLocal<Throwable> { |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override public String toString() { |
| return String.format("FFDC Exception State [lastSeen = '" + get() + "']"); |
| } |
| |
| } |
| } |