de.fub.bytecode.generic
Class BranchHandle

java.lang.Object
  |
  +--de.fub.bytecode.generic.InstructionHandle
        |
        +--de.fub.bytecode.generic.BranchHandle

All Implemented Interfaces:

java.io.Serializable

public final class BranchHandle

extends InstructionHandle

BranchHandle is returned by specialized InstructionList.append() whenever a BranchInstruction is appended. This is useful when the target of this instruction is not known at time of creation and must be set later via setTarget().

Version:

$Id: BranchHandle.java,v 1.2 2001/05/09 09:26:57 dahm Exp $

Author:

M. Dahm

See Also:

InstructionHandle, Instruction, InstructionList, Serialized Form

Fields inherited from class de.fub.bytecode.generic.InstructionHandle

i_position

Method Summary

protected void	addHandle() Handle adds itself to the list of resuable handles.
int	getPosition()
InstructionHandle	getTarget()
void	setInstruction(Instruction i) Set new contents.
void	setTarget(InstructionHandle ih) Pass new target to instruction.
protected int	updatePosition(int offset, int max_offset) Called by InstructionList.setPositions when setting the position for every instruction.
void	updateTarget(InstructionHandle old_ih, InstructionHandle new_ih) Update target of instruction.

Methods inherited from class de.fub.bytecode.generic.InstructionHandle

accept, addAttribute, addTargeter, getAttribute, getInstruction, getNext, getPrev, getTargeters, hasTargeters, removeAllTargeters, removeAttribute, removeTargeter, swapInstruction, toString, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

addHandle

protected void addHandle()

Handle adds itself to the list of resuable handles.

Overrides:

addHandle in class InstructionHandle

getPosition

public int getPosition()

Overrides:

getPosition in class InstructionHandle

Following copied from class: de.fub.bytecode.generic.InstructionHandle

Returns:

the position, i.e., the byte code offset of the contained instruction. This is accurate only after InstructionList.setPositions() has been called.

updatePosition

protected int updatePosition(int offset,
                             int max_offset)

Description copied from class: InstructionHandle

Called by InstructionList.setPositions when setting the position for every instruction. In the presence of variable length instructions `setPositions()' performs multiple passes over the instruction list to calculate the correct (byte) positions and offsets by calling this function.

Overrides:

updatePosition in class InstructionHandle

Following copied from class: de.fub.bytecode.generic.InstructionHandle

Parameters:

offset - additional offset caused by preceding (variable length) instructions

max_offset - the maximum offset that may be caused by these instructions

Returns:

additional offset caused by possible change of this instruction's length

setTarget

public void setTarget(InstructionHandle ih)

Pass new target to instruction.

updateTarget

public void updateTarget(InstructionHandle old_ih,
                         InstructionHandle new_ih)

Update target of instruction.

getTarget

public InstructionHandle getTarget()

Returns:

target of instruction.

setInstruction

public void setInstruction(Instruction i)

Set new contents. Old instruction is disposed and may not be used anymore.

Overrides:

setInstruction in class InstructionHandle