edu.umd.cs.findbugs.ba
Class ValueNumber

java.lang.Object
  edu.umd.cs.findbugs.ba.ValueNumber

All Implemented Interfaces:

java.lang.Comparable<ValueNumber>

public class ValueNumber
extends java.lang.Object
implements java.lang.Comparable<ValueNumber>

A "value number" is a value produced somewhere in a methods. We use value numbers as dataflow values in Frames. When two frame slots have the same value number, then the same value is in both of those slots.

Instances of ValueNumbers produced by the same ValueNumberFactory are unique, so reference equality may be used to determine whether or not two value numbers are the same. In general, ValueNumbers from different factories cannot be compared.

Author:

David Hovemeyer

See Also:

ValueNumberAnalysis

Field Summary

(package private) int	flags Flags representing meta information about the value.
(package private) int	number The value number.
static int	RETURN_VALUE Flag specifying that this value was the return value of a called method.

Constructor Summary

ValueNumber(int number)
Constructor.

Method Summary

int	compareTo(ValueNumber other)
int	getFlags()
int	getNumber()
boolean	hasFlag(int flag)
void	setFlag(int flag)
void	setFlags(int flags)
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

number

int number

The value number.

flags

int flags

Flags representing meta information about the value.

RETURN_VALUE

public static final int RETURN_VALUE

Flag specifying that this value was the return value of a called method.

See Also:

Constant Field Values

Constructor Detail

ValueNumber

ValueNumber(int number)

Constructor.

Parameters:

number - the value number

Method Detail

getNumber

public int getNumber()

getFlags

public int getFlags()

setFlags

public void setFlags(int flags)

setFlag

public void setFlag(int flag)

hasFlag

public boolean hasFlag(int flag)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

compareTo

public int compareTo(ValueNumber other)

Specified by:

compareTo in interface java.lang.Comparable<ValueNumber>