ptolemy.copernicus.kernel
Class NullPointerAnalysis

java.lang.Object
  soot.toolkits.scalar.AbstractFlowAnalysis
      soot.toolkits.scalar.BranchedFlowAnalysis
          soot.toolkits.scalar.ForwardBranchedFlowAnalysis
              soot.jimple.toolkits.annotation.nullcheck.BranchedRefVarsAnalysis
                  ptolemy.copernicus.kernel.NullPointerAnalysis

public class NullPointerAnalysis
extends soot.jimple.toolkits.annotation.nullcheck.BranchedRefVarsAnalysis

An analysis that can determine, at any point in the code, if a local variable points to null. This is just a nice wrapper class for soot's BranchedRefVarsAnalysis.

Since:

Ptolemy II 4.0

Version:

$Id: NullPointerAnalysis.java,v 1.17 2005/07/08 19:57:16 cxh Exp $

Author:

Steve Neuendorffer

Accepted Rating:

Red (cxh)

Proposed Rating:

Red (cxh)

Field Summary

Fields inherited from class soot.jimple.toolkits.annotation.nullcheck.BranchedRefVarsAnalysis

emptySet, fullSet, kBottom, kNonNull, kNull, kTop, refTypeInstFieldBases, refTypeInstFields, refTypeLocals, refTypeStaticFields, refTypeValues, tempFlowSet, unitToAnalyzedChecksSet, unitToArrayRefChecksSet, unitToGenerateSet, unitToInstanceFieldRefChecksSet, unitToInstanceInvokeExprChecksSet, unitToLengthExprChecksSet, unitToPreserveSet

Fields inherited from class soot.toolkits.scalar.BranchedFlowAnalysis

unitToAfterBranchFlow, unitToAfterFallFlow

Fields inherited from class soot.toolkits.scalar.AbstractFlowAnalysis

filterUnitToBeforeFlow, graph, unitToBeforeFlow

Constructor Summary

NullPointerAnalysis(soot.toolkits.graph.UnitGraph g)

Method Summary

boolean	isAlwaysNullBefore(soot.Local local, soot.Unit unit) Return the set of other fields and locals that must reference the same object as the given field, at a point before the given unit.
boolean	isNeverNullBefore(soot.Local local, soot.Unit unit) Return the set of other fields and locals that must reference the same object as the given local, at a point before the given unit.

Methods inherited from class soot.jimple.toolkits.annotation.nullcheck.BranchedRefVarsAnalysis

anyRefInfo, copy, entryInitialFlow, flowThrough, getEquivalentValue, getKRefIntPair, isAlwaysNonNull, merge, newInitialFlow, refInfo, refInfo, treatTrapHandlersAsEntries

Methods inherited from class soot.toolkits.scalar.ForwardBranchedFlowAnalysis

doAnalysis, isForward

Methods inherited from class soot.toolkits.scalar.BranchedFlowAnalysis

getBranchFlowAfter, getFallFlowAfter, getFlowBefore

Methods inherited from class soot.toolkits.scalar.AbstractFlowAnalysis

customizeInitialFlowGraph, getFlowBefore, merge

Methods inherited from class java.lang.Object

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

Constructor Detail

NullPointerAnalysis

public NullPointerAnalysis(soot.toolkits.graph.UnitGraph g)

Method Detail

isAlwaysNullBefore

public boolean isAlwaysNullBefore(soot.Local local,
                                  soot.Unit unit)

Return the set of other fields and locals that must reference the same object as the given field, at a point before the given unit.

isNeverNullBefore

public boolean isNeverNullBefore(soot.Local local,
                                 soot.Unit unit)

Return the set of other fields and locals that must reference the same object as the given local, at a point before the given unit.