FindBugs™ 1.3.9

edu.umd.cs.findbugs.detect
Class UnnecessaryMath

java.lang.Object
  extended by edu.umd.cs.findbugs.visitclass.BetterVisitor
      extended by edu.umd.cs.findbugs.visitclass.PreorderVisitor
          extended by edu.umd.cs.findbugs.visitclass.AnnotationVisitor
              extended by edu.umd.cs.findbugs.visitclass.DismantleBytecode
                  extended by edu.umd.cs.findbugs.BytecodeScanningDetector
                      extended by edu.umd.cs.findbugs.detect.UnnecessaryMath
All Implemented Interfaces:
Detector, Priorities, StatelessDetector, Constants2, java.lang.Cloneable, org.apache.bcel.classfile.Visitor, org.apache.bcel.Constants

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.

Author:
Dave Brosius

Field Summary
 
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
 
Fields inherited from interface org.apache.bcel.Constants
AALOAD, AASTORE, ACC_ABSTRACT, ACC_ANNOTATION, ACC_BRIDGE, ACC_ENUM, ACC_FINAL, ACC_INTERFACE, ACC_NATIVE, ACC_PRIVATE, ACC_PROTECTED, ACC_PUBLIC, ACC_STATIC, ACC_STRICT, ACC_SUPER, ACC_SYNCHRONIZED, ACC_SYNTHETIC, ACC_TRANSIENT, ACC_VARARGS, ACC_VOLATILE, ACCESS_NAMES, ACONST_NULL, ALOAD, ALOAD_0, ALOAD_1, ALOAD_2, ALOAD_3, ANEWARRAY, ANEWARRAY_QUICK, ARETURN, ARRAYLENGTH, ASTORE, ASTORE_0, ASTORE_1, ASTORE_2, ASTORE_3, ATHROW, ATTR_ANNOTATION_DEFAULT, ATTR_CODE, ATTR_CONSTANT_VALUE, ATTR_DEPRECATED, ATTR_EXCEPTIONS, ATTR_INNER_CLASSES, ATTR_LINE_NUMBER_TABLE, ATTR_LOCAL_VARIABLE_TABLE, ATTR_LOCAL_VARIABLE_TYPE_TABLE, ATTR_PMG, ATTR_RUNTIMEINVISIBLE_ANNOTATIONS, ATTR_RUNTIMEINVISIBLE_PARAMETER_ANNOTATIONS, ATTR_RUNTIMEVISIBLE_ANNOTATIONS, ATTR_RUNTIMEVISIBLE_PARAMETER_ANNOTATIONS, ATTR_SIGNATURE, ATTR_SOURCE_FILE, ATTR_STACK_MAP, ATTR_SYNTHETIC, ATTR_UNKNOWN, ATTRIBUTE_NAMES, BALOAD, BASTORE, BIPUSH, BREAKPOINT, CALOAD, CASTORE, CHECKCAST, CHECKCAST_QUICK, CLASS_TYPE_NAMES, CONSTANT_Class, CONSTANT_Double, CONSTANT_Fieldref, CONSTANT_Float, CONSTANT_Integer, CONSTANT_InterfaceMethodref, CONSTANT_Long, CONSTANT_Methodref, CONSTANT_NameAndType, CONSTANT_NAMES, CONSTANT_String, CONSTANT_Utf8, CONSTRUCTOR_NAME, CONSUME_STACK, D2F, D2I, D2L, DADD, DALOAD, DASTORE, DCMPG, DCMPL, DCONST_0, DCONST_1, DDIV, DLOAD, DLOAD_0, DLOAD_1, DLOAD_2, DLOAD_3, DMUL, DNEG, DREM, DRETURN, DSTORE, DSTORE_0, DSTORE_1, DSTORE_2, DSTORE_3, DSUB, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, F2D, F2I, F2L, FADD, FALOAD, FASTORE, FCMPG, FCMPL, FCONST_0, FCONST_1, FCONST_2, FDIV, FLOAD, FLOAD_0, FLOAD_1, FLOAD_2, FLOAD_3, FMUL, FNEG, FREM, FRETURN, FSTORE, FSTORE_0, FSTORE_1, FSTORE_2, FSTORE_3, FSUB, GETFIELD, GETFIELD_QUICK, GETFIELD_QUICK_W, GETFIELD2_QUICK, GETSTATIC, GETSTATIC_QUICK, GETSTATIC2_QUICK, GOTO, GOTO_W, I2B, I2C, I2D, I2F, I2L, I2S, IADD, IALOAD, IAND, IASTORE, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, ICONST_M1, IDIV, IF_ACMPEQ, IF_ACMPNE, IF_ICMPEQ, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ICMPLT, IF_ICMPNE, IFEQ, IFGE, IFGT, IFLE, IFLT, IFNE, IFNONNULL, IFNULL, IINC, ILLEGAL_OPCODE, ILLEGAL_TYPE, ILOAD, ILOAD_0, ILOAD_1, ILOAD_2, ILOAD_3, IMPDEP1, IMPDEP2, IMUL, INEG, INSTANCEOF, INSTANCEOF_QUICK, INT2BYTE, INT2CHAR, INT2SHORT, INTERFACES_IMPLEMENTED_BY_ARRAYS, INVOKEINTERFACE, INVOKEINTERFACE_QUICK, INVOKENONVIRTUAL, INVOKENONVIRTUAL_QUICK, INVOKESPECIAL, INVOKESTATIC, INVOKESTATIC_QUICK, INVOKESUPER_QUICK, INVOKEVIRTUAL, INVOKEVIRTUAL_QUICK, INVOKEVIRTUAL_QUICK_W, INVOKEVIRTUALOBJECT_QUICK, IOR, IREM, IRETURN, ISHL, ISHR, ISTORE, ISTORE_0, ISTORE_1, ISTORE_2, ISTORE_3, ISUB, ITEM_Bogus, ITEM_Double, ITEM_Float, ITEM_InitObject, ITEM_Integer, ITEM_Long, ITEM_NAMES, ITEM_NewObject, ITEM_Null, ITEM_Object, IUSHR, IXOR, JSR, JSR_W, KNOWN_ATTRIBUTES, L2D, L2F, L2I, LADD, LALOAD, LAND, LASTORE, LCMP, LCONST_0, LCONST_1, LDC, LDC_QUICK, LDC_W, LDC_W_QUICK, LDC2_W, LDC2_W_QUICK, LDIV, LLOAD, LLOAD_0, LLOAD_1, LLOAD_2, LLOAD_3, LMUL, LNEG, LOOKUPSWITCH, LOR, LREM, LRETURN, LSHL, LSHR, LSTORE, LSTORE_0, LSTORE_1, LSTORE_2, LSTORE_3, LSUB, LUSHR, LXOR, MAJOR, MAJOR_1_1, MAJOR_1_2, MAJOR_1_3, MAJOR_1_4, MAJOR_1_5, MAX_ACC_FLAG, MAX_BYTE, MAX_CODE_SIZE, MAX_CP_ENTRIES, MAX_SHORT, MINOR, MINOR_1_1, MINOR_1_2, MINOR_1_3, MINOR_1_4, MINOR_1_5, MONITORENTER, MONITOREXIT, MULTIANEWARRAY, MULTIANEWARRAY_QUICK, NEW, NEW_QUICK, NEWARRAY, NO_OF_OPERANDS, NOP, OPCODE_NAMES, POP, POP2, PRODUCE_STACK, PUSH, PUTFIELD, PUTFIELD_QUICK, PUTFIELD_QUICK_W, PUTFIELD2_QUICK, PUTSTATIC, PUTSTATIC_QUICK, PUTSTATIC2_QUICK, RESERVED, RET, RETURN, SALOAD, SASTORE, SHORT_TYPE_NAMES, SIPUSH, STATIC_INITIALIZER_NAME, SWAP, SWITCH, T_ADDRESS, T_ARRAY, T_BOOLEAN, T_BYTE, T_CHAR, T_DOUBLE, T_FLOAT, T_INT, T_LONG, T_OBJECT, T_REFERENCE, T_SHORT, T_UNKNOWN, T_VOID, TABLESWITCH, TYPE_NAMES, TYPE_OF_OPERANDS, UNDEFINED, UNPREDICTABLE, WIDE
 
Constructor Summary
UnnecessaryMath(BugReporter bugReporter)
           
 
Method Summary
 void sawOpcode(int seen)
           
 void visit(org.apache.bcel.classfile.Code obj)
           
 
Methods inherited from class edu.umd.cs.findbugs.BytecodeScanningDetector
getClassContext, report, visitClassContext
 
Methods inherited from class edu.umd.cs.findbugs.visitclass.DismantleBytecode
afterOpcode, areOppositeBranches, atCatchBlock, beforeOpcode, getBranchFallThrough, getBranchOffset, getBranchTarget, getClassConstantOperand, getClassDescriptorOperand, getCodeByte, getConstantRefOperand, getDefaultSwitchOffset, getDottedClassConstantOperand, getDottedSigConstantOperand, getFieldDescriptorOperand, getIntConstant, getMaxPC, getMethodDescriptorOperand, getNameConstantOperand, getNextOpcode, getNextPC, getOpcode, getPC, getPrevOpcode, getRefConstantOperand, getRefFieldIsStatic, getRegisterOperand, getSigConstantOperand, getStringConstantOperand, getSwitchLabels, getSwitchOffsets, getXClassOperand, getXFieldOperand, getXMethodOperand, isBranch, isRegisterLoad, isRegisterStore, isRegisterStore, isReturn, isSwitch, isWideOpcode, printOpCode, sawBranchTo, sawClass, sawDouble, sawField, sawFloat, sawIMethod, sawInt, sawLong, sawMethod, sawOffset, sawRegister, sawString
 
Methods inherited from class edu.umd.cs.findbugs.visitclass.AnnotationVisitor
visit, visitAnnotation, 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, getNumberArguments, getNumberMethodArguments, getPackageName, getSizeOfSurroundingTryBlock, getSizeOfSurroundingTryBlock, getSourceFile, getStringFromIndex, getSuperclassName, getSurroundingCaughtExceptions, getThisClass, getXClass, getXField, getXMethod, setupVisitorForClass, shouldVisit, visitAfter, visitCode, visitConstantPool, visitingField, visitingMethod, visitInnerClasses, visitJavaClass, visitLineNumberTable, visitLocalVariableTable
 
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, visitCodeException, visitConstantClass, visitConstantDouble, visitConstantFieldref, visitConstantFloat, visitConstantInteger, visitConstantInterfaceMethodref, visitConstantLong, visitConstantMethodref, visitConstantNameAndType, visitConstantString, visitConstantUtf8, visitConstantValue, visitDeprecated, visitExceptionTable, visitField, visitInnerClass, visitLineNumber, visitLocalVariable, visitLocalVariableTypeTable, visitMethod, visitSignature, visitSourceFile, visitStackMap, visitStackMapEntry, visitSynthetic, visitUnknown
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface edu.umd.cs.findbugs.StatelessDetector
clone
 

Constructor Detail

UnnecessaryMath

public UnnecessaryMath(BugReporter bugReporter)
Method Detail

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

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