Package edu.umd.cs.findbugs.ba

Interface ResourceTracker<Resource>

All Known Implementing Classes:
StreamResourceTracker
public interface ResourceTracker<Resource>
A ResourceTracker is used with ResourceValueAnalysis to determine where in a method a certain kind of resource is created, and to model the effect of instructions on the state of that resource.
Author:
David Hovemeyer
See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    ResourceValueFrameModelingVisitor
    createVisitor(Resource resource, org.apache.bcel.generic.ConstantPoolGen cpg)
    Create a ResourceValueFrameModelingVisitor to model the effect of instructions on the state of the resource.
    boolean
    ignoreExceptionEdge(Edge edge, Resource resource, org.apache.bcel.generic.ConstantPoolGen cpg)
    Determine whether the analysis should ignore given exception edge.
    boolean
    ignoreImplicitExceptions(Resource resource)
    Determine whether the analysis should ignore exception edges on which only implicit exceptions are propagated.
    boolean
    isParamInstance(Resource resource, int slot)
    Return if the given parameter slot contains the resource instance upon entry to the method.
    boolean
    isResourceClose(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg, Resource resource, ResourceValueFrame frame)
    Determine if the given instruction is the site where a resource is closed.
    Resource
    isResourceCreation(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg)
    Determine if the given instruction is the site where a resource is created.
    boolean
    mightCloseResource(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg)
    Determine if the given instruction is the site where a resource is closed.

  • Method Details

    • isResourceCreation

      Resource isResourceCreation(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg) throws DataflowAnalysisException
      Determine if the given instruction is the site where a resource is created.
      Parameters:
      basicBlock - basic block containing the instruction
      handle - the instruction
      cpg - the ConstantPoolGen for the method
      Returns:
      an opaque Resource object if it is a creation site, or null if it is not a creation site
      Throws:
      DataflowAnalysisException

    • isResourceClose

      boolean isResourceClose(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg, Resource resource, ResourceValueFrame frame) throws DataflowAnalysisException
      Determine if the given instruction is the site where a resource is closed.
      Parameters:
      basicBlock - basic block containing the instruction
      handle - the instruction
      cpg - the ConstantPoolGen for the method
      resource - the resource, as returned by isResourceCreation()
      frame - the ResourceValueFrame representing the stack prior to executing the instruction
      Returns:
      true if the resource is closed here, false otherwise
      Throws:
      DataflowAnalysisException

    • mightCloseResource

      boolean mightCloseResource(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg) throws DataflowAnalysisException
      Determine if the given instruction is the site where a resource is closed.
      Parameters:
      basicBlock - basic block containing the instruction
      handle - the instruction
      cpg - the ConstantPoolGen for the method
      Returns:
      true if the resource is closed here, false otherwise
      Throws:
      DataflowAnalysisException

    • createVisitor

      ResourceValueFrameModelingVisitor createVisitor(Resource resource, org.apache.bcel.generic.ConstantPoolGen cpg)
      Create a ResourceValueFrameModelingVisitor to model the effect of instructions on the state of the resource.
      Parameters:
      resource - the resource we are tracking
      cpg - the ConstantPoolGen of the method
      Returns:
      a ResourceValueFrameModelingVisitor

    • ignoreImplicitExceptions

      boolean ignoreImplicitExceptions(Resource resource)
      Determine whether the analysis should ignore exception edges on which only implicit exceptions are propagated. This allows different resource types to be tracked with varying precision. For example, we might want to ignore implicit exceptions for stream objects, but treat them as significant for database resources.
      Parameters:
      resource - the resource being tracked
      Returns:
      true if implicit exceptions are significant, false if they should be ignore

    • ignoreExceptionEdge

      boolean ignoreExceptionEdge(Edge edge, Resource resource, org.apache.bcel.generic.ConstantPoolGen cpg)
      Determine whether the analysis should ignore given exception edge. This allows the analysis to customize which kinds of exceptions are significant.
      Parameters:
      edge - the exception edge
      resource - the resource
      cpg - the ConstantPoolGen
      Returns:
      true if exception edge should be ignored, false if it should be considered

    • isParamInstance

      boolean isParamInstance(Resource resource, int slot)
      Return if the given parameter slot contains the resource instance upon entry to the method. This is for resources passed as parameters.
      Parameters:
      resource - the resource
      slot - the local variable slot
      Returns:
      true if the slot contains the resource instance, false otherwise