/* 
 * Copyright (C) 2001 The Apache Software Foundation. All rights reserved.
 * For details on use and redistribution please refer to the 
 * LICENSE file included with these sources."
 */

package org.apache.fop.apps;

import org.xml.sax.SAXException;


/**
 * Exception thrown when FOP has a problem
 */
public class FOPException extends Exception {

    private static final String EXCEPTION_SEPARATOR = "\n---------\n";
    
    private Throwable _exception;
    
    /**
     * create a new FOP Exception
     *
     * @param message descriptive message
     */
    public FOPException(String message) {
        super(message);
    }
    public FOPException(Throwable e) {
        super(e.getMessage());
	setException(e);
    }
    
    public FOPException(String message, Throwable e) {
        super(message);
	setException(e);
    }
    
    protected void setException(Throwable t) 
    {
	_exception = t;
    }
    
    public Throwable getException() 
    {
	return _exception;
    }

    protected Throwable getRootException() 
    {
	Throwable result = _exception;
	
	if (result instanceof SAXException) {
	    result = ((SAXException)result).getException();
	}
	if (result instanceof java.lang.reflect.InvocationTargetException) {
	    result = ((java.lang.reflect.InvocationTargetException)result).getTargetException();
	}
	if (result != _exception) {
	    return result;
	}
	return null;
    }
    	    
    
    public void printStackTrace() 
    {
	synchronized (System.err) {
	    super.printStackTrace();
	    if (_exception != null) {
		System.err.println(EXCEPTION_SEPARATOR);
		_exception.printStackTrace();
	    }
	    if (getRootException() != null) {
		System.err.println(EXCEPTION_SEPARATOR);
		getRootException().printStackTrace();
	    }
	}
    }
    
    public void printStackTrace(java.io.PrintStream stream)  
    {
	synchronized (stream) {
	    super.printStackTrace(stream);
	    if (_exception != null) {
		stream.println(EXCEPTION_SEPARATOR);
		_exception.printStackTrace(stream);
	    }
	    if (getRootException() != null) {
		System.err.println(EXCEPTION_SEPARATOR);
		getRootException().printStackTrace(stream);
	    }
	}
    }
    
    public void printStackTrace(java.io.PrintWriter writer)  
    {
	synchronized (writer) {
	    super.printStackTrace(writer);
	    if (_exception != null) {
		writer.println(EXCEPTION_SEPARATOR);
		_exception.printStackTrace(writer);
	    }
	    if (getRootException() != null) {
		System.err.println(EXCEPTION_SEPARATOR);
		getRootException().printStackTrace(writer);
	    }
	}
    }
    
}