Package com.mebigfatguy.fbcontrib.detect

Class SuspiciousComparatorReturnValues

java.lang.Object
edu.umd.cs.findbugs.visitclass.BetterVisitor
edu.umd.cs.findbugs.visitclass.PreorderVisitor
edu.umd.cs.findbugs.visitclass.AnnotationVisitor
edu.umd.cs.findbugs.visitclass.DismantleBytecode
edu.umd.cs.findbugs.BytecodeScanningDetector
com.mebigfatguy.fbcontrib.detect.SuspiciousComparatorReturnValues
All Implemented Interfaces:
edu.umd.cs.findbugs.Detector, edu.umd.cs.findbugs.Priorities, org.apache.bcel.classfile.Visitor
@CustomUserValue public class SuspiciousComparatorReturnValues extends edu.umd.cs.findbugs.BytecodeScanningDetector
looks for class that implement Comparator or Comparable, and whose compare or compareTo methods return constant values only, but that don't represent the three possible choice (a negative number, 0, and a positive number).

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private final edu.umd.cs.findbugs.BugReporter
    bugReporter
     
    private static List<CompareSpec>
    compareClasses
     
    private int
    furthestBranchTarget
     
    private MethodInfo
    methodInfo
     
    private Integer
    sawConstant
     
    private boolean
    seenNegative
     
    private boolean
    seenPositive
     
    private boolean
    seenUnconditionalNonZero
     
    private boolean
    seenZero
     
    private edu.umd.cs.findbugs.OpcodeStack
    stack
     

    Fields inherited from class edu.umd.cs.findbugs.visitclass.DismantleBytecode

    codeBytes, lineNumberTable, M_BR, M_CP, M_INT, M_PAD, M_R, M_UINT

    Fields inherited from interface edu.umd.cs.findbugs.Priorities

    EXP_PRIORITY, HIGH_PRIORITY, IGNORE_PRIORITY, LOW_PRIORITY, NORMAL_PRIORITY

  • Constructor Summary

    Constructors
    Constructor
    Description
    SuspiciousComparatorReturnValues(edu.umd.cs.findbugs.BugReporter bugReporter)
    constructs a SCRV detector given the reporter to report bugs on

  • Method Summary

    Modifier and Type
    Method
    Description
    private void
    processIntegerReturn()
    processes an IRETURN looking for Const and categorizes them as negative, zero or positive.
    void
    sawOpcode(int seen)
    implements the visitor to look for returns of constant values, and records them for being negative, zero or positive.
    void
    visitClassContext(edu.umd.cs.findbugs.ba.ClassContext classContext)
    implements the visitor to actually iterate twice over this class, once for compareTo and once for compare.
    void
    visitCode(org.apache.bcel.classfile.Code obj)
    implements the visitor to check to see what Const were returned from a comparator.

    Methods inherited from class edu.umd.cs.findbugs.BytecodeScanningDetector

    getClassContext, report, shouldVisitCode

    Methods inherited from class edu.umd.cs.findbugs.visitclass.DismantleBytecode

    afterOpcode, areOppositeBranches, atCatchBlock, beforeOpcode, getBranchFallThrough, getBranchOffset, getBranchTarget, getClassConstantOperand, getClassDescriptorOperand, getCodeByte, getConstantRefOperand, getDefaultSwitchOffset, getDottedClassConstantOperand, getFieldDescriptorOperand, getIntConstant, getLongConstant, getMaxPC, getMethodDescriptorOperand, getNameConstantOperand, getNextCodeByte, getNextOpcode, getNextPC, getOpcode, getPC, getPrevOpcode, getRefConstantOperand, getRefFieldIsStatic, getRegisterOperand, getSigConstantOperand, getStringConstantOperand, getSwitchLabels, getSwitchOffsets, getXClassOperand, getXFieldOperand, getXMethodOperand, isBranch, isMethodCall, isRegisterLoad, isRegisterStore, isRegisterStore, isReturn, isShift, isSwitch, isWideOpcode, printOpCode, sawBranchTo, sawClass, sawDouble, sawField, sawFloat, sawIMethod, sawInt, sawLong, sawMethod, sawRegister, sawString, visit

    Methods inherited from class edu.umd.cs.findbugs.visitclass.AnnotationVisitor

    getAnnotationParameterAsEnum, getAnnotationParameterAsString, getAnnotationParameterAsStringArray, visitAnnotation, visitAnnotation, visitParameterAnnotation, visitParameterAnnotation, visitSyntheticParameterAnnotation

    Methods inherited from class edu.umd.cs.findbugs.visitclass.PreorderVisitor

    amVisitingMainMethod, asUnsignedByte, doVisitMethod, getClassDescriptor, getClassName, getCode, getConstantPool, getDottedClassName, getDottedFieldSig, getDottedMethodSig, getDottedSuperclassName, getField, getFieldDescriptor, getFieldIsStatic, getFieldName, getFieldSig, getFullyQualifiedFieldName, getFullyQualifiedMethodName, getMethod, getMethodDescriptor, getMethodName, getMethodSig, getMethodVisitOrder, getNumberArguments, getNumberMethodArguments, getPackageName, getSizeOfSurroundingTryBlock, getSizeOfSurroundingTryBlock, getSourceFile, getStringFromIndex, getSuperclassName, getSurroundingCaughtExceptions, getSurroundingCaughtExceptions, getSurroundingCaughtExceptionTypes, getSurroundingTryBlock, getSurroundingTryBlock, getThisClass, getXClass, getXField, getXMethod, hasInterestingClass, hasInterestingMethod, isVisitMethodsInCallOrder, setupVisitorForClass, setVisitMethodsInCallOrder, shouldVisit, toString, visitAfter, visitAfter, visitAnnotationDefault, visitAnnotationEntry, visitBootstrapMethods, visitConstantInvokeDynamic, visitConstantMethodHandle, visitConstantMethodType, visitConstantModule, visitConstantPackage, visitConstantPool, visitEnclosingMethod, visitingField, visitingMethod, visitInnerClasses, visitJavaClass, visitLineNumberTable, visitLocalVariableTable, visitMethodParameters, visitParameterAnnotationEntry, visitStackMap, visitStackMapEntry

    Methods inherited from class edu.umd.cs.findbugs.visitclass.BetterVisitor

    clone, report, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visitCodeException, visitConstantClass, visitConstantDouble, visitConstantFieldref, visitConstantFloat, visitConstantInteger, visitConstantInterfaceMethodref, visitConstantLong, visitConstantMethodref, visitConstantNameAndType, visitConstantString, visitConstantUtf8, visitConstantValue, visitDeprecated, visitExceptionTable, visitField, visitInnerClass, visitLineNumber, visitLocalVariable, visitLocalVariableTypeTable, visitMethod, visitSignature, visitSourceFile, visitSynthetic, visitUnknown

    Methods inherited from class java.lang.Object

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

    Methods inherited from interface org.apache.bcel.classfile.Visitor

    visitConstantDynamic, visitMethodParameter, visitModule, visitModuleExports, visitModuleMainClass, visitModuleOpens, visitModulePackages, visitModuleProvides, visitModuleRequires, visitNestHost, visitNestMembers, visitRecord, visitRecordComponent, visitStackMapType

  • Field Details

    • compareClasses

      private static List<CompareSpec> compareClasses

    • stack

      private edu.umd.cs.findbugs.OpcodeStack stack

    • bugReporter

      private final edu.umd.cs.findbugs.BugReporter bugReporter

    • methodInfo

      private MethodInfo methodInfo

    • seenNegative

      private boolean seenNegative

    • seenPositive

      private boolean seenPositive

    • seenZero

      private boolean seenZero

    • seenUnconditionalNonZero

      private boolean seenUnconditionalNonZero

    • furthestBranchTarget

      private int furthestBranchTarget

    • sawConstant

      private Integer sawConstant

  • Constructor Details

    • SuspiciousComparatorReturnValues

      public SuspiciousComparatorReturnValues(edu.umd.cs.findbugs.BugReporter bugReporter)
      constructs a SCRV detector given the reporter to report bugs on
      Parameters:
      bugReporter - the sync of bug reports

  • Method Details

    • visitClassContext

      public void visitClassContext(edu.umd.cs.findbugs.ba.ClassContext classContext)
      implements the visitor to actually iterate twice over this class, once for compareTo and once for compare.
      Specified by:
      visitClassContext in interface edu.umd.cs.findbugs.Detector
      Overrides:
      visitClassContext in class edu.umd.cs.findbugs.BytecodeScanningDetector
      Parameters:
      classContext - the currently parsed class

    • visitCode

      public void visitCode(org.apache.bcel.classfile.Code obj)
      implements the visitor to check to see what Const were returned from a comparator. If no Const were returned it can't determine anything, however if only Const were returned, it looks to see if negative positive and zero was returned. It also looks to see if a non zero value is returned unconditionally. While it is possible that later check is ok, it usually means something is wrong.
      Specified by:
      visitCode in interface org.apache.bcel.classfile.Visitor
      Overrides:
      visitCode in class edu.umd.cs.findbugs.visitclass.PreorderVisitor
      Parameters:
      obj - the currently parsed code block

    • sawOpcode

      public void sawOpcode(int seen)
      implements the visitor to look for returns of constant values, and records them for being negative, zero or positive. It also records unconditional returns of non zero values
      Overrides:
      sawOpcode in class edu.umd.cs.findbugs.visitclass.DismantleBytecode
      Parameters:
      seen - the currently parsed opcode

    • processIntegerReturn

      private void processIntegerReturn()
      processes an IRETURN looking for Const and categorizes them as negative, zero or positive. it also records a unconditional return of a non zero value Throws StopOpcodeParsingException if a return value (constant) is indeterminate