001 /* RemoteException.java -- common superclass for exceptions in java.rmi
002 Copyright (c) 1996, 1997, 1998, 1999, 2002, 2006
003 Free Software Foundation, Inc.
004
005 This file is part of GNU Classpath.
006
007 GNU Classpath is free software; you can redistribute it and/or modify
008 it under the terms of the GNU General Public License as published by
009 the Free Software Foundation; either version 2, or (at your option)
010 any later version.
011
012 GNU Classpath is distributed in the hope that it will be useful, but
013 WITHOUT ANY WARRANTY; without even the implied warranty of
014 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 General Public License for more details.
016
017 You should have received a copy of the GNU General Public License
018 along with GNU Classpath; see the file COPYING. If not, write to the
019 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
020 02110-1301 USA.
021
022 Linking this library statically or dynamically with other modules is
023 making a combined work based on this library. Thus, the terms and
024 conditions of the GNU General Public License cover the whole
025 combination.
026
027 As a special exception, the copyright holders of this library give you
028 permission to link this library with independent modules to produce an
029 executable, regardless of the license terms of these independent
030 modules, and to copy and distribute the resulting executable under
031 terms of your choice, provided that you also meet, for each linked
032 independent module, the terms and conditions of the license of that
033 module. An independent module is a module which is not derived from
034 or based on this library. If you modify this library, you may extend
035 this exception to your version of the library, but you are not
036 obligated to do so. If you do not wish to do so, delete this
037 exception statement from your version. */
038
039 package java.rmi;
040
041 import java.io.IOException;
042
043 /**
044 * The superclass of exceptions related to RMI (remote method invocation).
045 * Classes that implement <code>java.rmi.Remote</code> should list this
046 * exception in their throws clause.
047 *
048 * @author unknown
049 * @since 1.1
050 * @status updated to 1.4
051 */
052 public class RemoteException extends IOException
053 {
054 /**
055 * Compatible with JDK 1.2+.
056 */
057 private static final long serialVersionUID = -5148567311918794206l;
058
059 /**
060 * The cause of this exception. This pre-dates the exception chaining
061 * of Throwable; and although you can change this field, you are wiser
062 * to leave it alone.
063 *
064 * @serial the exception cause
065 */
066 public Throwable detail;
067
068 /**
069 * Create an exception with no message, and cause initialized to null.
070 */
071 public RemoteException()
072 {
073 this(null, null);
074 }
075
076 /**
077 * Create an exception with the given message, and cause initialized to null.
078 *
079 * @param s the message
080 */
081 public RemoteException(String s)
082 {
083 this(s, null);
084 }
085
086 /**
087 * Create an exception with the given message and cause.
088 *
089 * @param s the message
090 * @param e the cause
091 */
092 public RemoteException(String s, Throwable e)
093 {
094 super(s);
095 initCause(e);
096 detail = e;
097 }
098
099 /**
100 * This method returns a message indicating what went wrong, in this
101 * format:
102 * <code>super.getMessage() + (detail == null ? ""
103 * : "; nested exception is:\n\t" + detail)</code>.
104 *
105 * @return the chained message
106 */
107 public String getMessage()
108 {
109 if (detail == this || detail == null)
110 return super.getMessage();
111 return super.getMessage() + "; nested exception is:\n\t" + detail;
112 }
113
114 /**
115 * Returns the cause of this exception. Note that this may not be the
116 * original cause, thanks to the <code>detail</code> field being public
117 * and non-final (yuck). However, to avoid violating the contract of
118 * Throwable.getCause(), this returns null if <code>detail == this</code>,
119 * as no exception can be its own cause.
120 *
121 * @return the cause
122 * @since 1.4
123 */
124 public Throwable getCause()
125 {
126 return detail == this ? null : detail;
127 }
128 }