jef.dna.instructions.impl
Class Dup

java.lang.Object
  jef.dna.instructions.impl.InstructionAncestor
      jef.dna.instructions.impl.Dup

All Implemented Interfaces:

java.lang.Cloneable, Instruction, BytesCountable

public class Dup
extends InstructionAncestor

This class maps the DUP bytecode instruction which duplicates the value found at the top of the operand stack, and pushes the copy of the top of it: as a result at the top of the operans stack there will be two equal doubles.

Author:

Francesco Russo (frusso@cs.unibo.it)

Field Summary

Fields inherited from class jef.dna.instructions.impl.InstructionAncestor

logger, opCode, operands, operandsCount

Constructor Summary

Dup()
Creates a new instance of Dup

Method Summary

int	updateRefs(int offset) This method must implement the logic necessary to update all the references to constant pool table's entries contained within the bytecode instruction.

Methods inherited from class jef.dna.instructions.impl.InstructionAncestor

clone, fromArray, getBytesCount, getOpCode, getOperands, getOperandsCount, setOpCode, setOperands, setOperandsCountPosticipated, toArray

Methods inherited from class java.lang.Object

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

Constructor Detail

Dup

public Dup()

Creates a new instance of Dup

Method Detail

updateRefs

public int updateRefs(int offset)

This method must implement the logic necessary to update all the references to constant pool table's entries contained within the bytecode instruction.

Specified by:

updateRefs in interface Instruction

Overrides:

updateRefs in class InstructionAncestor

Parameters:

offset - The offset used for updating expressed as number of cpt's entries to be skipped

Returns:

int The number of processed words within the current bytecode instruction