001: /*
002: * @(#)ChainableException.java
003: *
004: * Copyright (C) 2002-2003 Matt Albrecht
005: * groboclown@users.sourceforge.net
006: * http://groboutils.sourceforge.net
007: *
008: * Part of the GroboUtils package at:
009: * http://groboutils.sourceforge.net
010: *
011: * Permission is hereby granted, free of charge, to any person obtaining a
012: * copy of this software and associated documentation files (the "Software"),
013: * to deal in the Software without restriction, including without limitation
014: * the rights to use, copy, modify, merge, publish, distribute, sublicense,
015: * and/or sell copies of the Software, and to permit persons to whom the
016: * Software is furnished to do so, subject to the following conditions:
017: *
018: * The above copyright notice and this permission notice shall be included in
019: * all copies or substantial portions of the Software.
020: *
021: * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
022: * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
023: * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
024: * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
025: * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
026: * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
027: * DEALINGS IN THE SOFTWARE.
028: */
029: package net.sourceforge.groboutils.util.throwable.v1;
030:
031: import java.io.PrintStream;
032: import java.io.PrintWriter;
033:
034: /**
035: * General chainable exception, for pseudo-JDK 1.4 support.
036: *
037: * @author Matt Albrecht <a href="mailto:groboclown@users.sourceforge.net">groboclown@users.sourceforge.net</a>
038: * @version $Date: 2003/09/23 19:54:07 $
039: * @since July 7, 2002
040: */
041: public class ChainableException extends Exception implements
042: IChainableException {
043: /**
044: * @serial
045: */
046: private ChainableExceptionHelper ceh;
047:
048: public ChainableException() {
049: super ();
050: this .ceh = new ChainableExceptionHelper(this );
051: }
052:
053: public ChainableException(String message) {
054: super (message);
055: this .ceh = new ChainableExceptionHelper(this );
056: }
057:
058: public ChainableException(Throwable cause) {
059: super ();
060: this .ceh = new ChainableExceptionHelper(this , cause);
061: }
062:
063: public ChainableException(Throwable cause, String message) {
064: this (message, cause);
065: }
066:
067: public ChainableException(String message, Throwable cause) {
068: super (message);
069: this .ceh = new ChainableExceptionHelper(this , cause);
070: }
071:
072: /**
073: * JDK 1.4 compatible method.
074: * <P>
075: * <i>from the JDK 1.4 documentation:</i>
076: * <BLOCKQUOTE>
077: * Returns the cause of this throwable or <tt>null</tt> if the cause is
078: * nonexistent or unknown. (The cause is the throwable that caused this
079: * throwable to get thrown.)
080: * <P>
081: * This implementation returns the cause that was supplied via one of the
082: * constructors requiring a <tt>Throwable</tt>, or that was set after
083: * creation with the <tt>initCause( Throwable )</tt> method. While it is
084: * typically unnecessary to override this method, a subclass can override
085: * it to return a cause set by some other means. This is appropriate for a
086: * "legacy chained throwable" that predates the addition of chained
087: * exceptions to <tt>Throwable</tt>. Note that it is not necessary to
088: * override any of the <tt>PrintStackTrace</tt> methods, all of which
089: * invoke the getCause method to determine the cause of a throwable.
090: * </BLOCKQUOTE>
091: *
092: * @return the cause of this throwable or <tt>null</tt> if the cause is
093: * nonexistent or unknown.
094: */
095: public synchronized Throwable getCause() {
096: return this .ceh.getCause();
097: }
098:
099: /**
100: * JDK 1.4 compatible method.
101: * <P>
102: * <i>from the JDK 1.4 documentation:</i>
103: * <BLOCKQUOTE>
104: * Initializes the cause of this throwable to the specified value.
105: * (The cause is the throwable that caused this throwable to get thrown.)
106: * <P>
107: * This method can be called at most once. It is generally called from
108: * within the constructor, or immediately after creating the throwable.
109: * If this throwable was created with Throwable(Throwable) or
110: * Throwable(String,Throwable), this method cannot be called even once.
111: * </BLOCKQUOTE>
112: *
113: * @param cause the cause (which is saved for later retrieval by the
114: * getCause() method). (A null value is permitted, and indicates
115: * that the cause is nonexistent or unknown.)
116: * @return a reference to this Throwable instance.
117: * @exception IllegalArgumentException if cause is this throwable.
118: * (A throwable cannot be its own cause.)
119: * @exception IllegalStateException if this throwable was created with
120: * Throwable(Throwable) or Throwable(String,Throwable), or this
121: * method has already been called on this throwable.
122: */
123: public synchronized Throwable initCause(Throwable cause) {
124: return this .ceh.initCause(cause);
125: }
126:
127: /**
128: * For non-JDK 1.4 compatible VMs, this overrides the original behavior
129: * to describe the underlying cause. Special logic is performed to ensure
130: * that no JDK 1.4 VM is being used when the inner exception is displayed
131: * (in order to prevent double printing).
132: */
133: public void printStackTrace(PrintStream ps) {
134: this .ceh.printStackTrace(ps);
135: }
136:
137: /**
138: * For non-JDK 1.4 compatible VMs, this overrides the original behavior
139: * to describe the underlying cause. Special logic is performed to ensure
140: * that no JDK 1.4 VM is being used when the inner exception is displayed
141: * (in order to prevent double printing).
142: */
143: public void printStackTrace(PrintWriter pw) {
144: this.ceh.printStackTrace(pw);
145: }
146: }
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