Class StreamResourceTracker

java.lang.Object
edu.umd.cs.findbugs.detect.StreamResourceTracker
All Implemented Interfaces:
ResourceTracker<Stream>
public class StreamResourceTracker extends Object implements ResourceTracker<Stream>
Resource tracker which determines where streams are created, and how they are used within the method.

  • Field Details

    • streamFactoryList

      private final StreamFactory[] streamFactoryList

    • lookupFailureCallback

      private final RepositoryLookupFailureCallback lookupFailureCallback

    • resourceCollection

      private ResourceCollection<Stream> resourceCollection

    • streamOpenLocationMap

      private final Map<Location,Stream> streamOpenLocationMap
      Map of locations where streams are opened to the actual Stream objects.

    • uninterestingStreamEscapeSet

      private final HashSet<Stream> uninterestingStreamEscapeSet
      Set of all open locations and escapes of uninteresting streams.

    • streamEscapeSet

      private final TreeSet<StreamEscape> streamEscapeSet
      Set of all (potential) stream escapes.

    • streamEquivalenceMap

      private final Map<Stream, StreamEquivalenceClass> streamEquivalenceMap
      Map of individual streams to equivalence classes. Any time a stream "A" is wrapped with a stream "B", "A" and "B" belong to the same equivalence class. If any stream in an equivalence class is closed, then we consider all of the streams in the equivalence class as having been closed.

  • Constructor Details

    • StreamResourceTracker

      public StreamResourceTracker(StreamFactory[] streamFactoryList, RepositoryLookupFailureCallback lookupFailureCallback)
      Constructor.
      Parameters:
      streamFactoryList - array of StreamFactory objects which determine where streams are created
      lookupFailureCallback - used when class hierarchy lookups fail

  • Method Details

    • setResourceCollection

      public void setResourceCollection(ResourceCollection<Stream> resourceCollection)
      Set the precomputed ResourceCollection for the method.

    • addStreamEscape

      public void addStreamEscape(Stream source, Location target)
      Indicate that a stream escapes at the given target Location.
      Parameters:
      source - the Stream that is escaping
      target - the target Location (where the stream escapes)

    • markTransitiveUninterestingStreamEscapes

      public void markTransitiveUninterestingStreamEscapes()
      Transitively mark all streams into which uninteresting streams (such as System.out) escape. This handles the rule that wrapping an uninteresting stream makes the wrapper uninteresting as well.

    • isUninterestingStreamEscape

      public boolean isUninterestingStreamEscape(Stream stream)
      Determine if an uninteresting stream escapes at given location. markTransitiveUninterestingStreamEscapes() should be called first.
      Parameters:
      stream - the stream
      Returns:
      true if an uninteresting stream escapes at the location

    • addStreamOpenLocation

      public void addStreamOpenLocation(Location streamOpenLocation, Stream stream)
      Indicate that a stream is constructed at this Location.
      Parameters:
      streamOpenLocation - the Location
      stream - the Stream opened at this Location

    • getStreamEquivalenceClass

      public StreamEquivalenceClass getStreamEquivalenceClass(Stream stream)
      Get the equivalence class for given stream. May only be called if markTransitiveUninterestingStreamEscapes() has been called.
      Parameters:
      stream - the stream
      Returns:
      the set containing the equivalence class for the given stream

    • isStreamOpenLocation

      private boolean isStreamOpenLocation(Location location)
      Determine if given Location is a stream open location point.
      Parameters:
      location - the Location

    • isResourceCreation

      public Stream isResourceCreation(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg)
      Description copied from interface: ResourceTracker
      Determine if the given instruction is the site where a resource is created.
      Specified by:
      isResourceCreation in interface ResourceTracker<Stream>
      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

    • isResourceOpen

      public boolean isResourceOpen(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg, Stream resource, ResourceValueFrame frame)

    • isResourceClose

      public boolean isResourceClose(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg, Stream resource, ResourceValueFrame frame)
      Description copied from interface: ResourceTracker
      Determine if the given instruction is the site where a resource is closed.
      Specified by:
      isResourceClose in interface ResourceTracker<Stream>
      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

    • mightCloseResource

      public boolean mightCloseResource(BasicBlock basicBlock, org.apache.bcel.generic.InstructionHandle handle, org.apache.bcel.generic.ConstantPoolGen cpg) throws DataflowAnalysisException
      Description copied from interface: ResourceTracker
      Determine if the given instruction is the site where a resource is closed.
      Specified by:
      mightCloseResource in interface ResourceTracker<Stream>
      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

      public ResourceValueFrameModelingVisitor createVisitor(Stream resource, org.apache.bcel.generic.ConstantPoolGen cpg)
      Description copied from interface: ResourceTracker
      Create a ResourceValueFrameModelingVisitor to model the effect of instructions on the state of the resource.
      Specified by:
      createVisitor in interface ResourceTracker<Stream>
      Parameters:
      resource - the resource we are tracking
      cpg - the ConstantPoolGen of the method
      Returns:
      a ResourceValueFrameModelingVisitor

    • ignoreImplicitExceptions

      public boolean ignoreImplicitExceptions(Stream resource)
      Description copied from interface: ResourceTracker
      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.
      Specified by:
      ignoreImplicitExceptions in interface ResourceTracker<Stream>
      Parameters:
      resource - the resource being tracked
      Returns:
      true if implicit exceptions are significant, false if they should be ignore

    • ignoreExceptionEdge

      public boolean ignoreExceptionEdge(Edge edge, Stream resource, org.apache.bcel.generic.ConstantPoolGen cpg)
      Description copied from interface: ResourceTracker
      Determine whether the analysis should ignore given exception edge. This allows the analysis to customize which kinds of exceptions are significant.
      Specified by:
      ignoreExceptionEdge in interface ResourceTracker<Stream>
      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

      public boolean isParamInstance(Stream resource, int slot)
      Description copied from interface: ResourceTracker
      Return if the given parameter slot contains the resource instance upon entry to the method. This is for resources passed as parameters.
      Specified by:
      isParamInstance in interface ResourceTracker<Stream>
      Parameters:
      resource - the resource
      slot - the local variable slot
      Returns:
      true if the slot contains the resource instance, false otherwise