de.rwth.dfa.jvm.samples
Class SSAbstraction

java.lang.Object
  |
  +--de.rwth.dfa.jvm.samples.SSAbstraction

All Implemented Interfaces:

Abstraction

public class SSAbstraction

extends java.lang.Object

implements Abstraction

Implementation of a stack size abstraction. It can be used to determine the number of elements on the operand stack for each instruction of a JVM method.

Version:

$Id: SSAbstraction.java,v 1.3 2002/09/17 06:53:53 mohnen Exp $

Author:

Markus Mohnen

Inner Class Summary

protected class

SSAbstraction.SSFunction This class models the functions of this abstraction.

Inner classes inherited from class de.rwth.dfa.jvm.Abstraction

Abstraction.Default

Field Summary

protected de.fub.bytecode.generic.ConstantPoolGen	cpg A constant pool generator for the constant pool of the methods class.
protected CompleteLattice	lattice Contains the instance of SSLattice used by this abstraction.
protected int	maxStack The maximal number of elements of the operand stack inside the method of this abstraction.

Fields inherited from interface de.rwth.dfa.jvm.Abstraction

DIRECTION_BACKWARD, DIRECTION_FORWARD, QUANTIFIER_ALL, QUANTIFIER_EXISTS

Constructor Summary

SSAbstraction(int maxStack, de.fub.bytecode.classfile.ConstantPool constantPool)
Creates a new SSAbstraction instance.

SSAbstraction(int maxStack, de.fub.bytecode.generic.ConstantPoolGen constantPoolGen)
Creates a new SSAbstraction instance.

Method Summary

Function	getAbstract(de.fub.bytecode.generic.InstructionHandle ih) Returns a new instance of SSFunction.
Function	getAbstract(InstructionHandleVector ihv) Returns the value of the default implementation in Abstraction.Default.
int	getDirection() Returns DIRECTION_FORWARD.
java.lang.Object	getInitialValue(de.fub.bytecode.generic.InstructionHandle o, boolean isRoot) Determined the initial stack size at an instruction.
java.lang.Object	getInitialValue(InstructionHandleVector ihv, boolean isRoot) Returns the value of the default implementation in Abstraction.Default.
Lattice	getLattice() Returns this abstractions instance of SSLattice.
int	getQuantifier() Returns QUANTIFIER_ALL

Methods inherited from class java.lang.Object

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

Field Detail

lattice

protected CompleteLattice lattice

Contains the instance of SSLattice used by this abstraction.

maxStack

protected int maxStack

The maximal number of elements of the operand stack inside the method of this abstraction.

cpg

protected de.fub.bytecode.generic.ConstantPoolGen cpg

A constant pool generator for the constant pool of the methods class.

Constructor Detail

SSAbstraction

public SSAbstraction(int maxStack,
                     de.fub.bytecode.generic.ConstantPoolGen constantPoolGen)

Creates a new SSAbstraction instance.

Parameters:

maxStack - an int value: The maximal number of elements on the operand stack of the method to consider.

constantPoolGen - a ConstantPoolGen value: The constant pool generator for the method.

SSAbstraction

public SSAbstraction(int maxStack,
                     de.fub.bytecode.classfile.ConstantPool constantPool)

Creates a new SSAbstraction instance.

Parameters:

maxStack - an int value: The maximal number of elements on the operand stack of the method to consider.

constantPool - a ConstantPool value: The constant pool for the method.

Method Detail

getDirection

public int getDirection()

Returns DIRECTION_FORWARD.

Specified by:

getDirection in interface Abstraction

Returns:

an int value

getQuantifier

public int getQuantifier()

Returns QUANTIFIER_ALL

Specified by:

getQuantifier in interface Abstraction

Returns:

an int value

getLattice

public Lattice getLattice()

Returns this abstractions instance of SSLattice.

Specified by:

getLattice in interface Abstraction

Returns:

a Lattice value

getInitialValue

public java.lang.Object getInitialValue(de.fub.bytecode.generic.InstructionHandle o,
                                        boolean isRoot)

Determined the initial stack size at an instruction. Returns 0 for the method entry, 1 for exception handler entries and the top element for all other instructions.

Specified by:

getInitialValue in interface Abstraction

Parameters:

o - an InstructionHandle value

isRoot - a boolean value

Returns:

an Object value

getAbstract

public Function getAbstract(de.fub.bytecode.generic.InstructionHandle ih)

Returns a new instance of SSFunction.

Specified by:

getAbstract in interface Abstraction

Parameters:

ih - an InstructionHandle value

Returns:

a Function value

getInitialValue

public java.lang.Object getInitialValue(InstructionHandleVector ihv,
                                        boolean isRoot)

Returns the value of the default implementation in Abstraction.Default.

Specified by:

getInitialValue in interface Abstraction

Parameters:

ihv - an InstructionHandleVector value

isRoot - a boolean value

Returns:

an Object value

getAbstract

public Function getAbstract(InstructionHandleVector ihv)

Returns the value of the default implementation in Abstraction.Default.

Specified by:

getAbstract in interface Abstraction

Parameters:

ihv - an InstructionHandleVector value

Returns:

a Function value