/* ======================================================================== * JCommon : a free general purpose class library for the Java(tm) platform * ======================================================================== * * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors. * * Project Info: http://www.jfree.org/jcommon/index.html * * This library is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This library 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 Lesser General Public * License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, * USA. * * [Java is a trademark or registered trademark of Sun Microsystems, Inc. * in the United States and other countries.] * * ----------------------- * StackableException.java * ----------------------- * (C)opyright 2002-2004, by Thomas Morgner and Contributors. * * Original Author: Thomas Morgner; * Contributor(s): David Gilbert (for Object Refinery Limited); * * $Id: StackableException.java,v 1.3 2005/11/14 10:56:55 mungady Exp $ * * Changes * ------- * 06-Dec-2002 : Initial version * 10-Dec-2002 : Fixed issues reported by Checkstyle (DG); * 29-Apr-2003 : Distilled from the JFreeReport project and moved into JCommon * */ package org.jfree.util; import java.io.PrintStream; import java.io.PrintWriter; /** * A baseclass for exceptions, which could have parent exceptions. These parent exceptions * are raised in a subclass and are now wrapped into a subclass of this Exception. *
* The parents are printed when this exception is printed. This class exists mainly for
* debugging reasons, as with them it is easier to detect the root cause of an error.
*
*
*
* @author Thomas Morgner
*/
public abstract class StackableException extends Exception {
/** The parent exception. */
private Exception parent;
/**
* Creates a StackableRuntimeException with no message and no parent.
*/
public StackableException() {
super();
}
/**
* Creates an exception.
*
* @param message the exception message.
* @param ex the parent exception.
*/
public StackableException(final String message, final Exception ex) {
super(message);
this.parent = ex;
}
/**
* Creates an exception.
*
* @param message the exception message.
*/
public StackableException(final String message) {
super(message);
}
/**
* Returns the parent exception (possibly null).
*
* @return the parent exception.
*/
public Exception getParent() {
return this.parent;
}
/**
* Prints the stack trace to the specified stream.
*
* @param stream the output stream.
*/
public void printStackTrace(final PrintStream stream) {
super.printStackTrace(stream);
if (getParent() != null) {
stream.println("ParentException: ");
getParent().printStackTrace(stream);
}
}
/**
* Prints the stack trace to the specified writer.
*
* @param writer the writer.
*/
public void printStackTrace(final PrintWriter writer) {
super.printStackTrace(writer);
if (getParent() != null) {
writer.println("ParentException: ");
getParent().printStackTrace(writer);
}
}
/**
* Prints this Throwable
and its backtrace to the
* standard error stream. This method prints a stack trace for this
* Throwable
object on the error output stream that is
* the value of the field System.err
. The first line of
* output contains the result of the {@link #toString()} method for
* this object. Remaining lines represent data previously recorded by
* the method {@link #fillInStackTrace()}. The format of this
* information depends on the implementation, but the following
* example may be regarded as typical:
*
* This example was produced by running the program: ** java.lang.NullPointerException * at MyClass.mash(MyClass.java:9) * at MyClass.crunch(MyClass.java:6) * at MyClass.main(MyClass.java:3) *
* * @see System#err */ public void printStackTrace() { synchronized (System.err) { printStackTrace(System.err); } } }* * class MyClass { * * public static void main(String[] argv) { * crunch(null); * } * static void crunch(int[] a) { * mash(a); * } * * static void mash(int[] b) { * System.out.println(b[0]); * } * } *