jode/jode/src/net/sf/jode/flow/Jump.java

/* Jump Copyright (C) 1998-2002 Jochen Hoenicke.
 *
 * This program 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, or (at your option)
 * any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; see the file COPYING.LESSER.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Id$
 */

package net.sf.jode.flow;

/**
 * This class represents an unconditional jump.
 */
public class Jump {
    /**
     * The structured block that precedes this jump.
     */
    StructuredBlock prev;
    /**
     * The destination block of this jump, null if not known, or illegal.
     */
    FlowBlock destination;

    /**
     * The jumps in a flow block, that have the same destination, are
     * in a link list.  This field points to the next jump in this link.
     */
    Jump next;

    /**
     * The stack map.  This tells how many objects are on stack at
     * begin of the flow block, and to what locals they are maped.
     * @see FlowBlock#mapStackToLocal
     */
    VariableStack stackMap;

    public Jump (FlowBlock dest) {
        this.destination = dest;
    }

    public Jump (Jump jump) {
	destination = jump.destination;
	next = jump.next;
	jump.next = this;
    }

    /**
     * Print the source code for this structured block.  This handles
     * everything that is unique for all structured blocks and calls
     * dumpInstruction afterwards.
     * @param writer The tabbed print writer, where we print to.
     */
    public void dumpSource(net.sf.jode.decompiler.TabbedPrintWriter writer)
        throws java.io.IOException
    {
        if (destination == null)
            writer.println ("GOTO null-ptr!!!!!");
        else
            writer.println("GOTO "+destination.getLabel());
    }
}