com.ibm.wala.fixedpoint.impl
Class NullaryStatement<T extends IVariable>

java.lang.Object
  com.ibm.wala.util.graph.impl.NodeWithNumber
      com.ibm.wala.fixpoint.AbstractStatement<T,NullaryOperator<T>>
          com.ibm.wala.fixedpoint.impl.NullaryStatement<T>

All Implemented Interfaces:

IFixedPointStatement<T>, INodeWithNumber

Direct Known Subclasses:

BasicNullaryStatement

public abstract class NullaryStatement<T extends IVariable>
extends AbstractStatement<T,NullaryOperator<T>>

Represents a single step, restricted to a nullary operator.

Field Summary

protected T

lhs The operands

Constructor Summary

protected

NullaryStatement(T lhs) Constructor for case of one operand on the right-hand side.

Method Summary

boolean	equals(java.lang.Object o)
byte	evaluate() Evaluate this equation, setting a new value for the left-hand side.
T	getLHS() Return the left-hand side of this equation.
T[]	getRHS() returns the list of free variables appearing in the right-hand side of the statement
int	hashCode() Subclasses must implement this, to prevent non-determinism.
boolean	hasVariable(T cell) Does this equation contain an appearance of a given cell?

Methods inherited from class com.ibm.wala.fixpoint.AbstractStatement

getOperator, getOrderNumber, toString

Methods inherited from class com.ibm.wala.util.graph.impl.NodeWithNumber

getGraphNodeId, setGraphNodeId

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.ibm.wala.util.graph.INodeWithNumber

getGraphNodeId, setGraphNodeId

Field Detail

lhs

protected final T extends IVariable lhs

The operands

Constructor Detail

NullaryStatement

protected NullaryStatement(T lhs)

Constructor for case of one operand on the right-hand side.

Parameters:

lhs - the lattice cell set by this equation

Method Detail

evaluate

public byte evaluate()

Evaluate this equation, setting a new value for the left-hand side.

Returns:

true if the lhs value changed. false otherwise

getLHS

public T getLHS()

Return the left-hand side of this equation.

Returns:

the lattice cell this equation computes

hasVariable

public boolean hasVariable(T cell)

Does this equation contain an appearance of a given cell?

Parameters:

cell - the cell in question

Returns:

true or false

equals

public boolean equals(java.lang.Object o)

Specified by:

equals in class AbstractStatement<T extends IVariable,NullaryOperator<T extends IVariable>>

hashCode

public int hashCode()

Description copied from class: AbstractStatement

Subclasses must implement this, to prevent non-determinism.

Specified by:

hashCode in class AbstractStatement<T extends IVariable,NullaryOperator<T extends IVariable>>

getRHS

public T[] getRHS()
                             throws java.lang.UnsupportedOperationException

Description copied from interface: IFixedPointStatement

returns the list of free variables appearing in the right-hand side of the statement

Throws:

java.lang.UnsupportedOperationException