Package com.mebigfatguy.fbcontrib.detect
Class BuryingLogic
- 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.BuryingLogic
-
- All Implemented Interfaces:
edu.umd.cs.findbugs.Detector
,edu.umd.cs.findbugs.Priorities
,edu.umd.cs.findbugs.visitclass.Constants2
,org.apache.bcel.classfile.Visitor
,org.apache.bcel.Constants
public class BuryingLogic extends edu.umd.cs.findbugs.BytecodeScanningDetector
looks for relatively large if blocks of code, where you unconditionally return from them, and then follow that with an unconditional return of a small block. This places the bulk of the logic to the right indentation-wise, making it more difficult to read than needed. It would be better to invert the logic of the if block, and immediately return, allowing the bulk of the logic to be move to the left, for easier reading.
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description (package private) static class
BuryingLogic.IfBlock
represents the byte offset code range of code that is executed inside an if block(package private) static class
BuryingLogic.IfBlocks
represents all the if blocks in a method
-
Field Summary
Fields Modifier and Type Field Description private BuryingLogic.IfBlock
activeUnconditional
if an previous if block has been closed off with a return, hold onto it.private edu.umd.cs.findbugs.BugReporter
bugReporter
private static java.lang.String
BURY_LOGIC_LOW_RATIO_PROPERTY
private static java.lang.String
BURY_LOGIC_NORMAL_RATIO_PROPERTY
private java.util.BitSet
casePositions
private java.util.BitSet
catchPCs
private java.util.BitSet
gotoBranchPCs
private BuryingLogic.IfBlocks
ifBlocks
private boolean
lookingForResetOp
if we've processed an if block, we want to avoid else ifs, so don't start looking for a new if branch, until some instruction that can't be part of a conditional is foundprivate static double
LOW_BUG_RATIO_LIMIT
private double
lowBugRatioLimit
private static double
NORMAL_BUG_RATIO_LIMIT
private double
normalBugRatioLimit
private static java.util.BitSet
resetOps
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 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_SYPER, ACC_TRANSIENT, ACC_VARARGS, ACC_VOLATILE, ACCESS_NAMES, ACONST_NULL, ALOAD, ALOAD_0, ALOAD_1, ALOAD_2, ALOAD_3, ANEWARRAY, ANEWARRAY_QUICK, APPEND_FRAME, APPEND_FRAME_MAX, ARETURN, ARRAYLENGTH, ASTORE, ASTORE_0, ASTORE_1, ASTORE_2, ASTORE_3, ATHROW, ATTR_ANNOTATION_DEFAULT, ATTR_CODE, ATTR_CONSTANT_VALUE, ATTR_DEPRECATED, ATTR_ENCLOSING_METHOD, ATTR_EXCEPTIONS, ATTR_INNER_CLASSES, ATTR_LINE_NUMBER_TABLE, ATTR_LOCAL_VARIABLE_TABLE, ATTR_LOCAL_VARIABLE_TYPE_TABLE, ATTR_PMG, ATTR_RUNTIME_VISIBLE_ANNOTATIONS, ATTR_RUNTIME_VISIBLE_PARAMETER_ANNOTATIONS, ATTR_RUNTIMEIN_VISIBLE_ANNOTATIONS, ATTR_RUNTIMEIN_VISIBLE_PARAMETER_ANNOTATIONS, ATTR_SIGNATURE, ATTR_SOURCE_FILE, ATTR_STACK_MAP, ATTR_STACK_MAP_TABLE, ATTR_SYNTHETIC, ATTR_UNKNOWN, ATTRIBUTE_NAMES, BALOAD, BASTORE, BIPUSH, BREAKPOINT, CALOAD, CASTORE, CHECKCAST, CHECKCAST_QUICK, CHOP_FRAME, CHOP_FRAME_MAX, CLASS_TYPE_NAMES, CONSTANT_Class, CONSTANT_Double, CONSTANT_Fieldref, CONSTANT_Float, CONSTANT_Integer, CONSTANT_InterfaceMethodref, CONSTANT_InvokeDynamic, CONSTANT_Long, CONSTANT_MethodHandle, CONSTANT_Methodref, CONSTANT_MethodType, 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, FULL_FRAME, 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, INVOKEDYNAMIC, 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, MAJOR_1_6, MAJOR_1_7, MAJOR_1_8, 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, MINOR_1_6, MINOR_1_7, MINOR_1_8, 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, SAME_FRAME, SAME_FRAME_EXTENDED, SAME_FRAME_MAX, SAME_LOCALS_1_STACK_ITEM_FRAME, SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED, SAME_LOCALS_1_STACK_ITEM_FRAME_MAX, 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
Constructors Constructor Description BuryingLogic(edu.umd.cs.findbugs.BugReporter bugReporter)
constructs a BL detector given the reporter to report bugs on
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description private boolean
gotoAcrossPC(int pc)
returns whether the last downward branching jump seen crosses over the current locationprivate boolean
isResetOp(int seen)
determines if this opcode couldn't be part of a conditional expression or at least is very unlikely to be so.void
sawOpcode(int seen)
the difficult problem is to figure out when you are at the bottom of an if/else chain when all the above if/else blocks leave via returns.void
visitClassContext(edu.umd.cs.findbugs.ba.ClassContext classContext)
implements the visitor to reset the opcode stack, and initialize if tracking collectionsvoid
visitCode(org.apache.bcel.classfile.Code obj)
-
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
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, getSurroundingTryBlock, getSurroundingTryBlock, getThisClass, getXClass, getXField, getXMethod, hasInterestingClass, hasInterestingMethod, isVisitMethodsInCallOrder, setupVisitorForClass, setVisitMethodsInCallOrder, shouldVisit, toString, visitAfter, visitAfter, visitAnnotationDefault, visitAnnotationEntry, visitConstantPool, visitEnclosingMethod, visitingField, visitingMethod, visitInnerClasses, visitJavaClass, visitLineNumberTable, visitLocalVariableTable, visitStackMapTable, visitStackMapTableEntry
-
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, visitStackMap, visitStackMapEntry, visitSynthetic, visitUnknown
-
-
-
-
Field Detail
-
BURY_LOGIC_LOW_RATIO_PROPERTY
private static final java.lang.String BURY_LOGIC_LOW_RATIO_PROPERTY
- See Also:
- Constant Field Values
-
BURY_LOGIC_NORMAL_RATIO_PROPERTY
private static final java.lang.String BURY_LOGIC_NORMAL_RATIO_PROPERTY
- See Also:
- Constant Field Values
-
LOW_BUG_RATIO_LIMIT
private static final double LOW_BUG_RATIO_LIMIT
- See Also:
- Constant Field Values
-
NORMAL_BUG_RATIO_LIMIT
private static final double NORMAL_BUG_RATIO_LIMIT
- See Also:
- Constant Field Values
-
resetOps
private static final java.util.BitSet resetOps
-
bugReporter
private edu.umd.cs.findbugs.BugReporter bugReporter
-
stack
private edu.umd.cs.findbugs.OpcodeStack stack
-
ifBlocks
private BuryingLogic.IfBlocks ifBlocks
-
activeUnconditional
private BuryingLogic.IfBlock activeUnconditional
if an previous if block has been closed off with a return, hold onto it.
-
casePositions
private java.util.BitSet casePositions
-
lowBugRatioLimit
private double lowBugRatioLimit
-
normalBugRatioLimit
private double normalBugRatioLimit
-
catchPCs
private java.util.BitSet catchPCs
-
gotoBranchPCs
private java.util.BitSet gotoBranchPCs
-
lookingForResetOp
private boolean lookingForResetOp
if we've processed an if block, we want to avoid else ifs, so don't start looking for a new if branch, until some instruction that can't be part of a conditional is found
-
-
Method Detail
-
visitClassContext
public void visitClassContext(edu.umd.cs.findbugs.ba.ClassContext classContext)
implements the visitor to reset the opcode stack, and initialize if tracking collections- Specified by:
visitClassContext
in interfaceedu.umd.cs.findbugs.Detector
- Overrides:
visitClassContext
in classedu.umd.cs.findbugs.BytecodeScanningDetector
- Parameters:
classContext
- the currently parsed java class
-
visitCode
public void visitCode(org.apache.bcel.classfile.Code obj)
- Specified by:
visitCode
in interfaceorg.apache.bcel.classfile.Visitor
- Overrides:
visitCode
in classedu.umd.cs.findbugs.visitclass.PreorderVisitor
-
sawOpcode
public void sawOpcode(int seen)
the difficult problem is to figure out when you are at the bottom of an if/else chain when all the above if/else blocks leave via returns. then there is only one branch target to the statement after the last else, which is indistinquishable from a simple if/else.- Overrides:
sawOpcode
in classedu.umd.cs.findbugs.visitclass.DismantleBytecode
-
gotoAcrossPC
private boolean gotoAcrossPC(int pc)
returns whether the last downward branching jump seen crosses over the current location- Parameters:
pc
- the current location- Returns:
- if the last if statement branched over here
-
isResetOp
private boolean isResetOp(int seen)
determines if this opcode couldn't be part of a conditional expression or at least is very unlikely to be so.- Parameters:
seen
- the currently parse opcode- Returns:
- if this operation resets the looking for conditionals
-
-