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      1 /*
      2  * Copyright (c) 2001, 2004, Oracle and/or its affiliates. All rights reserved.
      3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
      4  *
      5  * This code is free software; you can redistribute it and/or modify it
      6  * under the terms of the GNU General Public License version 2 only, as
      7  * published by the Free Software Foundation.  Oracle designates this
      8  * particular file as subject to the "Classpath" exception as provided
      9  * by Oracle in the LICENSE file that accompanied this code.
     10  *
     11  * This code is distributed in the hope that it will be useful, but WITHOUT
     12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
     13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
     14  * version 2 for more details (a copy is included in the LICENSE file that
     15  * accompanied this code).
     16  *
     17  * You should have received a copy of the GNU General Public License version
     18  * 2 along with this work; if not, write to the Free Software Foundation,
     19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
     20  *
     21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
     22  * or visit www.oracle.com if you need additional information or have any
     23  * questions.
     24  */
     25 
     26 
     27 package java.util.logging;
     28 
     29 /**
     30  * ErrorManager objects can be attached to Handlers to process
     31  * any error that occurs on a Handler during Logging.
     32  * <p>
     33  * When processing logging output, if a Handler encounters problems
     34  * then rather than throwing an Exception back to the issuer of
     35  * the logging call (who is unlikely to be interested) the Handler
     36  * should call its associated ErrorManager.
     37  */
     38 
     39 public class ErrorManager {
     40    private boolean reported = false;
     41 
     42     /*
     43      * We declare standard error codes for important categories of errors.
     44      */
     45 
     46     /**
     47      * GENERIC_FAILURE is used for failure that don't fit
     48      * into one of the other categories.
     49      */
     50     public final static int GENERIC_FAILURE = 0;
     51     /**
     52      * WRITE_FAILURE is used when a write to an output stream fails.
     53      */
     54     public final static int WRITE_FAILURE = 1;
     55     /**
     56      * FLUSH_FAILURE is used when a flush to an output stream fails.
     57      */
     58     public final static int FLUSH_FAILURE = 2;
     59     /**
     60      * CLOSE_FAILURE is used when a close of an output stream fails.
     61      */
     62     public final static int CLOSE_FAILURE = 3;
     63     /**
     64      * OPEN_FAILURE is used when an open of an output stream fails.
     65      */
     66     public final static int OPEN_FAILURE = 4;
     67     /**
     68      * FORMAT_FAILURE is used when formatting fails for any reason.
     69      */
     70     public final static int FORMAT_FAILURE = 5;
     71 
     72     /**
     73      * The error method is called when a Handler failure occurs.
     74      * <p>
     75      * This method may be overridden in subclasses.  The default
     76      * behavior in this base class is that the first call is
     77      * reported to System.err, and subsequent calls are ignored.
     78      *
     79      * @param msg    a descriptive string (may be null)
     80      * @param ex     an exception (may be null)
     81      * @param code   an error code defined in ErrorManager
     82      */
     83     public synchronized void error(String msg, Exception ex, int code) {
     84         if (reported) {
     85             // We only report the first error, to avoid clogging
     86             // the screen.
     87             return;
     88         }
     89         reported = true;
     90         String text = "java.util.logging.ErrorManager: " + code;
     91         if (msg != null) {
     92             text = text + ": " + msg;
     93         }
     94         System.err.println(text);
     95         if (ex != null) {
     96             ex.printStackTrace();
     97         }
     98     }
     99 }
    100