com.mebigfatguy.fbcontrib.detect

Class NeedlessMemberCollectionSynchronization

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.NeedlessMemberCollectionSynchronization

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 NeedlessMemberCollectionSynchronization
extends edu.umd.cs.findbugs.BytecodeScanningDetector

looks for private collection members, either static or instance, that are only initialized in the clinit or init, but are synchronized. This is not necessary as the constructor or static initializer are guaranteed to be thread safe.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) static class	NeedlessMemberCollectionSynchronization.FieldInfo holds information about a field, namely the annotation and whether the collection is synchronized.
private static class	NeedlessMemberCollectionSynchronization.State

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Map<java.lang.Integer,java.lang.String>	aliases
private edu.umd.cs.findbugs.BugReporter	bugReporter
private java.lang.String	className
private static org.apache.bcel.classfile.JavaClass	collectionClass
private java.util.Map<java.lang.String,NeedlessMemberCollectionSynchronization.FieldInfo>	collectionFields
private static org.apache.bcel.classfile.JavaClass	mapClass
private static java.util.Set<java.lang.String>	modifyingMethods
private edu.umd.cs.findbugs.OpcodeStack	stack
private NeedlessMemberCollectionSynchronization.State	state
private static java.util.Set<java.lang.String>	syncCollections

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
NeedlessMemberCollectionSynchronization(edu.umd.cs.findbugs.BugReporter bugReporter) constructs a NMCS detector given the reporter to report bugs on

Method Summary

Modifier and Type	Method and Description
private boolean	isSyncCollectionCreation(int seen) returns whether this instruction is creating a synchronized collection
private void	processCollectionStore() sets the source line annotation of a store to a collection if that collection is synchronized.
private void	removeCollectionParameters() removes collection fields that are passed to other methods as arguments
private void	sawCLInitOpcode(int seen) handle <clinit> blocks by looking for putstatic calls referencing synchronized collections
private void	sawInitOpcode(int seen) handle <init> blocks by looking for putfield calls referencing synchronized collections
private void	sawMethodOpcode(int seen) handles regular methods by looking for methods on collections that are modifying and removes those collections from the ones under review
void	sawOpcode(int seen) implements the visitor to call the approriate visitor based on state
void	visitClassContext(edu.umd.cs.findbugs.ba.ClassContext classContext) implements the visitor to clear the collectionFields and stack and to report collections that remain unmodified out of clinit or init
void	visitCode(org.apache.bcel.classfile.Code obj) implements the visitor to set the state based on the type of method being parsed
void	visitField(org.apache.bcel.classfile.Field obj) implements the visitor to find collection fields

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, visitMethod, visitSignature, visitSourceFile, visitStackMap, visitStackMapEntry, visitSynthetic, visitUnknown

Methods inherited from class java.lang.Object

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

Field Detail

collectionClass

private static org.apache.bcel.classfile.JavaClass collectionClass

mapClass

private static org.apache.bcel.classfile.JavaClass mapClass

syncCollections

private static java.util.Set<java.lang.String> syncCollections

modifyingMethods

private static java.util.Set<java.lang.String> modifyingMethods

bugReporter

private edu.umd.cs.findbugs.BugReporter bugReporter

collectionFields

private java.util.Map<java.lang.String,NeedlessMemberCollectionSynchronization.FieldInfo> collectionFields

aliases

private java.util.Map<java.lang.Integer,java.lang.String> aliases

stack

private edu.umd.cs.findbugs.OpcodeStack stack

state

private NeedlessMemberCollectionSynchronization.State state

className

private java.lang.String className

Constructor Detail

NeedlessMemberCollectionSynchronization

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

constructs a NMCS detector given the reporter to report bugs on

Parameters:

bugReporter - the sync of bug reports

Method Detail

visitClassContext

public void visitClassContext(edu.umd.cs.findbugs.ba.ClassContext classContext)

implements the visitor to clear the collectionFields and stack and to report collections that remain unmodified out of clinit or init

Specified by:

visitClassContext in interface edu.umd.cs.findbugs.Detector

Overrides:

visitClassContext in class edu.umd.cs.findbugs.BytecodeScanningDetector

Parameters:

classContext - the context object of the currently parsed class

visitField

public void visitField(org.apache.bcel.classfile.Field obj)

implements the visitor to find collection fields

Specified by:

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

Overrides:

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

Parameters:

obj - the context object of the currently parse field

visitCode

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

implements the visitor to set the state based on the type of method being parsed

Specified by:

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

Overrides:

visitCode in class edu.umd.cs.findbugs.visitclass.PreorderVisitor

Parameters:

obj - the context object of the currently parsed code block

sawOpcode

public void sawOpcode(int seen)

implements the visitor to call the approriate visitor based on state

Overrides:

sawOpcode in class edu.umd.cs.findbugs.visitclass.DismantleBytecode

Parameters:

seen - the opcode of the currently parsed instruction

sawCLInitOpcode

private void sawCLInitOpcode(int seen)

handle <clinit> blocks by looking for putstatic calls referencing synchronized collections

Parameters:

seen - the opcode of the currently parsed instruction

sawInitOpcode

private void sawInitOpcode(int seen)

handle <init> blocks by looking for putfield calls referencing synchronized collections

Parameters:

seen - the opcode of the currently parsed instruction

sawMethodOpcode

private void sawMethodOpcode(int seen)

handles regular methods by looking for methods on collections that are modifying and removes those collections from the ones under review

Parameters:

seen - the opcode of the currently parsed instruction

isSyncCollectionCreation

private boolean isSyncCollectionCreation(int seen)

returns whether this instruction is creating a synchronized collection

Parameters:

seen - the opcode of the currently parsed instruction

Returns:

whether a synchronized collection has just been created

processCollectionStore

private void processCollectionStore()

sets the source line annotation of a store to a collection if that collection is synchronized.

removeCollectionParameters

private void removeCollectionParameters()

removes collection fields that are passed to other methods as arguments