Class UnnecessaryMath

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

edu.umd.cs.findbugs.detect.UnnecessaryMath

All Implemented Interfaces:

Detector, Priorities, StatelessDetector, Cloneable, org.apache.bcel.classfile.Visitor

public class UnnecessaryMath
extends BytecodeScanningDetector
implements StatelessDetector

Find occurrences of Math using constants, where the result of the calculation can be determined statically. Replacing the math formula with the constant performs better, and sometimes is more accurate.

Field Summary

Fields

Modifier and Type	Field	Description
private static final Set<String>	anyMethods
private final BugReporter	bugReporter
private double	constValue
private static final Set<String>	oneMethods
(package private) static final int	SEEN_DCONST
(package private) static final int	SEEN_NOTHING
private int	state
private static final Set<String>	zeroMethods

Fields inherited from class DismantleBytecode

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

Fields inherited from interface Priorities

EXP_PRIORITY, HIGH_PRIORITY, IGNORE_PRIORITY, LOW_PRIORITY, NORMAL_PRIORITY

Constructor Summary

Constructors

Constructor	Description
UnnecessaryMath(BugReporter bugReporter)

Method Summary

Modifier and Type	Method	Description
void	sawOpcode(int seen)
void	visit(org.apache.bcel.classfile.Code obj)
void	visitClassContext(ClassContext classContext)	Visit the ClassContext for a class which should be analyzed for instances of bug patterns.

Methods inherited from class BytecodeScanningDetector

getClassContext, report, shouldVisitCode

Methods inherited from class 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 AnnotationVisitor

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

Methods inherited from class 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 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 Object

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

Methods inherited from interface 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 Details

SEEN_NOTHING

static final int SEEN_NOTHING

See Also:

• Constant Field Values

SEEN_DCONST

static final int SEEN_DCONST

See Also:

• Constant Field Values

bugReporter

private final BugReporter bugReporter

state

private int state

constValue

private double constValue

zeroMethods

@StaticConstant
private static final Set<String> zeroMethods

oneMethods

@StaticConstant
private static final Set<String> oneMethods

anyMethods

@StaticConstant
private static final Set<String> anyMethods

Constructor Details

UnnecessaryMath

public UnnecessaryMath(BugReporter bugReporter)

Method Details

visitClassContext

public void visitClassContext(ClassContext classContext)

Description copied from interface: Detector

Visit the ClassContext for a class which should be analyzed for instances of bug patterns.

Specified by:

visitClassContext in interface Detector

Overrides:

visitClassContext in class BytecodeScanningDetector

Parameters:

classContext - the ClassContext

visit

public void visit(org.apache.bcel.classfile.Code obj)

Overrides:

visit in class DismantleBytecode

sawOpcode

public void sawOpcode(int seen)

Overrides:

sawOpcode in class DismantleBytecode