com.mebigfatguy.fbcontrib.detect

Class WriteOnlyCollection

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.MissingMethodsDetector

com.mebigfatguy.fbcontrib.detect.WriteOnlyCollection

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

@OpcodeStack.CustomUserValue
public class WriteOnlyCollection
extends MissingMethodsDetector

Looks for allocations and initializations of java collections, but that are never read from or accessed to gain information. This represents a collection of no use, and most probably can be removed. It is similar to a dead local store.

Field Summary

Fields

Modifier and Type	Field and Description
private static java.util.Set<java.lang.String>	collectionClasses
private static java.util.Set<FQMethod>	collectionFactoryMethods
private int	firstLocalRegister
private static java.util.Set<java.lang.String>	nonInformationalMethods

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_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 and Description
WriteOnlyCollection(edu.umd.cs.findbugs.BugReporter bugReporter) constructs a WOC detector given the reporter to report bugs on

Method Summary

Modifier and Type	Method and Description
protected boolean	doesObjectNeedToBeWatched(java.lang.String type) implements the MissingMethodsDetector to determine whether this class type is a collection
protected boolean	doesStaticFactoryReturnNeedToBeWatched(java.lang.String clsName, java.lang.String methodName, java.lang.String signature) implements the MissingMethodsDetector to determine whether this factory-like method returns a collection
protected boolean	isMethodThatShouldBeCalled(java.lang.String methodName) determines if the method is returns information that could be used by the caller
protected edu.umd.cs.findbugs.BugInstance	makeFieldBugInstance() implements the MissingMethodsDetector to generate a Bug Instance when a bug is found around collections stored in fields
protected edu.umd.cs.findbugs.BugInstance	makeLocalBugInstance() implements the MissingMethodsDetector to generate a Bug Instance when a bug is found around collections stored in a local variable
private static java.lang.String	noParamsReturnType(java.lang.Class<?> type)
void	sawOpcode(int seen) overrides the visitor to look for PUTFIELDS of collections
void	visitMethod(org.apache.bcel.classfile.Method obj) overrides the visitor to see what how many register slots are taken by parameters.

Methods inherited from class com.mebigfatguy.fbcontrib.detect.MissingMethodsDetector

clearSpecialField, getStack, processMethodParms, visitClassContext, visitCode, visitField

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, visitInnerClass, visitLineNumber, visitLocalVariable, visitLocalVariableTypeTable, visitSignature, visitSourceFile, visitStackMap, visitStackMapEntry, visitSynthetic, visitUnknown

Methods inherited from class java.lang.Object

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

Field Detail

collectionClasses

private static final java.util.Set<java.lang.String> collectionClasses

collectionFactoryMethods

private static final java.util.Set<FQMethod> collectionFactoryMethods

nonInformationalMethods

private static final java.util.Set<java.lang.String> nonInformationalMethods

firstLocalRegister

private int firstLocalRegister

Constructor Detail

WriteOnlyCollection

public WriteOnlyCollection(edu.umd.cs.findbugs.BugReporter bugReporter)

constructs a WOC detector given the reporter to report bugs on

Parameters:

bugReporter - the sync of bug reports

Method Detail

noParamsReturnType

private static java.lang.String noParamsReturnType(java.lang.Class<?> type)

visitMethod

public void visitMethod(org.apache.bcel.classfile.Method obj)

overrides the visitor to see what how many register slots are taken by parameters.

Specified by:

visitMethod in interface org.apache.bcel.classfile.Visitor

Overrides:

visitMethod in class edu.umd.cs.findbugs.visitclass.BetterVisitor

Parameters:

obj - the currently parsed method

sawOpcode

public void sawOpcode(int seen)

overrides the visitor to look for PUTFIELDS of collections

Overrides:

sawOpcode in class MissingMethodsDetector

Parameters:

seen - the currently parsed opcode

makeFieldBugInstance

protected edu.umd.cs.findbugs.BugInstance makeFieldBugInstance()

implements the MissingMethodsDetector to generate a Bug Instance when a bug is found around collections stored in fields

Specified by:

makeFieldBugInstance in class MissingMethodsDetector

Returns:

the BugInstance

makeLocalBugInstance

protected edu.umd.cs.findbugs.BugInstance makeLocalBugInstance()

implements the MissingMethodsDetector to generate a Bug Instance when a bug is found around collections stored in a local variable

Specified by:

makeLocalBugInstance in class MissingMethodsDetector

Returns:

the BugInstance

doesObjectNeedToBeWatched

protected boolean doesObjectNeedToBeWatched(@DottedClassName
                                            java.lang.String type)

implements the MissingMethodsDetector to determine whether this class type is a collection

Specified by:

doesObjectNeedToBeWatched in class MissingMethodsDetector

Parameters:

type - the class type to check

Returns:

whether this class is a collection

doesStaticFactoryReturnNeedToBeWatched

protected boolean doesStaticFactoryReturnNeedToBeWatched(java.lang.String clsName,
                                                         java.lang.String methodName,
                                                         java.lang.String signature)

implements the MissingMethodsDetector to determine whether this factory-like method returns a collection

Specified by:

doesStaticFactoryReturnNeedToBeWatched in class MissingMethodsDetector

Parameters:

clsName - the clsName the class name of the factory

methodName - the method name of the factory

signature - the signature of the factory method

Returns:

whether this class is a collection

isMethodThatShouldBeCalled

protected boolean isMethodThatShouldBeCalled(java.lang.String methodName)

determines if the method is returns information that could be used by the caller

Specified by:

isMethodThatShouldBeCalled in class MissingMethodsDetector

Parameters:

methodName - collection method name

Returns:

true if the caller could use the return value to learn something about the collection