Package edu.umd.cs.findbugs.detect
Class FindUselessControlFlow
- java.lang.Object
-
- All Implemented Interfaces:
Detector
,Priorities
,StatelessDetector
,java.lang.Cloneable
,org.apache.bcel.classfile.Visitor
public class FindUselessControlFlow extends BytecodeScanningDetector implements StatelessDetector
A Detector to look for useless control flow. For example,
if (argv.length == 1) ; System.out.println("Hello, " + argv[0]);
In this kind of bug, we'll see an ifcmp instruction where the IF target is the same as the fall-through target.
The idea for this detector came from Richard P. King, and the idea of looking for if instructions with identical branch and fall-through targets is from Mike Fagan.
-
-
Field Summary
Fields Modifier and Type Field Description private BugAccumulator
bugAccumulator
private static java.util.BitSet
ifInstructionSet
-
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 FindUselessControlFlow(BugReporter bugReporter)
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description static int
getNextSourceLine(org.apache.bcel.classfile.LineNumberTable lineNumbers, int sourceLine)
void
sawOpcode(int seen)
void
visit(org.apache.bcel.classfile.Code obj)
-
Methods inherited from class edu.umd.cs.findbugs.BytecodeScanningDetector
getClassContext, report, shouldVisitCode, visitClassContext
-
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
-
Methods inherited from class edu.umd.cs.findbugs.visitclass.AnnotationVisitor
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, visitCode, 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 edu.umd.cs.findbugs.StatelessDetector
clone
-
Methods inherited from interface org.apache.bcel.classfile.Visitor
visitConstantDynamic, visitMethodParameter, visitModule, visitModuleExports, visitModuleMainClass, visitModuleOpens, visitModulePackages, visitModuleProvides, visitModuleRequires, visitNestHost, visitNestMembers, visitRecord, visitRecordComponent, visitStackMapType
-
-
-
-
Field Detail
-
ifInstructionSet
private static final java.util.BitSet ifInstructionSet
-
bugAccumulator
private final BugAccumulator bugAccumulator
-
-
Constructor Detail
-
FindUselessControlFlow
public FindUselessControlFlow(BugReporter bugReporter)
-
-
Method Detail
-
visit
public void visit(org.apache.bcel.classfile.Code obj)
- Overrides:
visit
in classDismantleBytecode
-
sawOpcode
public void sawOpcode(int seen)
- Overrides:
sawOpcode
in classDismantleBytecode
-
getNextSourceLine
public static int getNextSourceLine(org.apache.bcel.classfile.LineNumberTable lineNumbers, int sourceLine)
-
-