| /* ErrorManager.java -- |
| A class for dealing with errors that a Handler encounters |
| during logging |
| Copyright (C) 2002, 2003 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package java.util.logging; |
| |
| /** |
| * An <code>ErrorManager</code> deals with errors that a <code>Handler</code> |
| * encounters while logging. |
| * |
| * @see Handler#setErrorManager(ErrorManager) |
| * |
| * @author Sascha Brawer (brawer@acm.org) |
| */ |
| public class ErrorManager |
| { |
| /* The values have been taken from Sun's public J2SE 1.4 API |
| * documentation. |
| * See http://java.sun.com/j2se/1.4/docs/api/constant-values.html |
| */ |
| |
| /** |
| * Indicates that there was a failure that does not readily |
| * fall into any of the other categories. |
| */ |
| public static final int GENERIC_FAILURE = 0; |
| |
| |
| /** |
| * Indicates that there was a problem upon writing to |
| * an output stream. |
| */ |
| public static final int WRITE_FAILURE = 1; |
| |
| |
| /** |
| * Indicates that there was a problem upon flushing |
| * an output stream. |
| */ |
| public static final int FLUSH_FAILURE = 2; |
| |
| |
| /** |
| * Indicates that there was a problem upon closing |
| * an output stream. |
| */ |
| public static final int CLOSE_FAILURE = 3; |
| |
| |
| /** |
| * Indicates that there was a problem upon opening |
| * an output stream. |
| */ |
| public static final int OPEN_FAILURE = 4; |
| |
| |
| /** |
| * Indicates that there was a problem upon formatting |
| * the message of a log record. |
| */ |
| public static final int FORMAT_FAILURE = 5; |
| |
| |
| /** |
| * Indicates whether the {@link #error} method of this ErrorManager |
| * has ever been used. |
| * |
| * Declared volatile in order to correctly support the |
| * double-checked locking idiom (once the revised Java Memory Model |
| * gets adopted); see Classpath bug #2944. |
| */ |
| private volatile boolean everUsed = false; |
| |
| |
| public ErrorManager() |
| { |
| } |
| |
| |
| /** |
| * Reports an error that occured upon logging. The default implementation |
| * emits the very first error to System.err, ignoring subsequent errors. |
| * |
| * @param message a message describing the error, or <code>null</code> if |
| * there is no suitable description. |
| * |
| * @param ex an exception, or <code>null</code> if the error is not |
| * related to an exception. |
| * |
| * @param errorCode one of the defined error codes, for example |
| * <code>ErrorManager.CLOSE_FAILURE</code>. |
| */ |
| public void error(String message, Exception ex, int errorCode) |
| { |
| if (everUsed) |
| return; |
| |
| synchronized (this) |
| { |
| /* The double check is intentional. If the first check was |
| * omitted, the monitor would have to be entered every time |
| * error() method was called. If the second check was |
| * omitted, the code below could be executed by multiple |
| * threads simultaneously. |
| * |
| * This is the 'double-checked locking' idiom, which is broken |
| * with the current version of the Java memory model. However, |
| * we assume that JVMs will have adopted a revised version of |
| * the Java Memory Model by the time GNU Classpath gains |
| * widespread acceptance. See Classpath bug #2944. |
| */ |
| if (everUsed) |
| return; |
| |
| everUsed = true; |
| } |
| |
| String codeMsg; |
| switch (errorCode) |
| { |
| case GENERIC_FAILURE: |
| codeMsg = "GENERIC_FAILURE"; |
| break; |
| |
| case WRITE_FAILURE: |
| codeMsg = "WRITE_FAILURE"; |
| break; |
| |
| case FLUSH_FAILURE: |
| codeMsg = "FLUSH_FAILURE"; |
| break; |
| |
| case CLOSE_FAILURE: |
| codeMsg = "CLOSE_FAILURE"; |
| break; |
| |
| case OPEN_FAILURE: |
| codeMsg = "OPEN_FAILURE"; |
| break; |
| |
| case FORMAT_FAILURE: |
| codeMsg = "FORMAT_FAILURE"; |
| break; |
| |
| default: |
| codeMsg = String.valueOf(errorCode); |
| break; |
| } |
| |
| System.err.println("Error upon logging: " + codeMsg); |
| if ((message != null) && (message.length() > 0)) |
| System.err.println(message); |
| |
| if (ex != null) |
| ex.printStackTrace(); |
| } |
| } |
| |