org.eclipse.jdt.internal.compiler.ast
Class CombinedBinaryExpression

java.lang.Object
  org.eclipse.jdt.internal.compiler.ast.ASTNode
      org.eclipse.jdt.internal.compiler.ast.Statement
          org.eclipse.jdt.internal.compiler.ast.Expression
              org.eclipse.jdt.internal.compiler.ast.OperatorExpression
                  org.eclipse.jdt.internal.compiler.ast.BinaryExpression
                      org.eclipse.jdt.internal.compiler.ast.CombinedBinaryExpression

All Implemented Interfaces:

OperatorIds, TypeConstants, TypeIds

public class CombinedBinaryExpression
extends BinaryExpression

CombinedBinaryExpression is an implementation of BinaryExpression that specifically attempts to mitigate the issues raised by expressions which have a very deep leftmost branch. It does so by maintaining a table of direct references to its subexpressions, and implementing non-recursive variants of the most significant recursive algorithms of its ancestors. The subexpressions table only holds intermediate binary expressions. Its role is to provide the reversed navigation through the left relationship of BinaryExpression to Expression. To cope with potentially very deep left branches, an instance of CombinedBinaryExpression is created once in a while, using variable thresholds held by arityMax. As a specific case, the topmost node of all binary expressions that are deeper than one is a CombinedBinaryExpression, but it has no references table.
Notes:

• CombinedBinaryExpression is not meant to behave in other ways than BinaryExpression in any observable respect;
• visitors that implement their own traversal upon binary expressions should consider taking advantage of combined binary expressions, or else face a risk of StackOverflowError upon deep instances;
• callers that need to change the operator should rebuild the expression from scratch, or else amend the references table as needed to cope with the resulting, separated expressions.

Field Summary

int	arity The number of consecutive binary expressions of this' left branch that bear the same operator as this. Notes: the presence of a CombinedBinaryExpression instance resets arity, even when its operator is compatible; this property is maintained by the parser.
static int	ARITY_MAX_MAX Upper limit for arityMax.
static int	ARITY_MAX_MIN Default lower limit for arityMax.
int	arityMax The threshold that will trigger the creation of the next full-fledged CombinedBinaryExpression.
static int	defaultArityMaxStartingValue Default value for the first term of the series of arityMax values.
BinaryExpression[]	referencesTable A table of references to the binary expressions of this' left branch.

Fields inherited from class org.eclipse.jdt.internal.compiler.ast.BinaryExpression

left, optimizedBooleanConstant, right

Fields inherited from class org.eclipse.jdt.internal.compiler.ast.OperatorExpression

OperatorSignatures

Fields inherited from class org.eclipse.jdt.internal.compiler.ast.Expression

constant, implicitConversion, resolvedType, statementEnd

Fields inherited from class org.eclipse.jdt.internal.compiler.ast.ASTNode

Bit1, Bit10, Bit11, Bit12, Bit13, Bit14, Bit15, Bit16, Bit17, Bit18, Bit19, Bit2, Bit20, Bit21, Bit22, Bit23, Bit24, Bit25, Bit26, Bit27, Bit28, Bit29, Bit3, Bit30, Bit31, Bit32, Bit32L, Bit33L, Bit34L, Bit35L, Bit36L, Bit37L, Bit38L, Bit39L, Bit4, Bit40L, Bit41L, Bit42L, Bit43L, Bit44L, Bit45L, Bit46L, Bit47L, Bit48L, Bit49L, Bit5, Bit50L, Bit51L, Bit52L, Bit53L, Bit54L, Bit55L, Bit56L, Bit57L, Bit58L, Bit59L, Bit6, Bit60L, Bit61L, Bit62L, Bit63L, Bit64L, Bit7, Bit8, Bit9, bits, BlockExit, ContainsAssertion, DepthMASK, DepthSHIFT, DidResolve, DisableUnnecessaryCastCheck, DiscardEnclosingInstance, DocumentedFallthrough, Empty, ErrorInSignature, FirstAssignmentToLocal, GenerateCheckcast, HasAbstractMethods, HasAllMethodBodies, HasBeenGenerated, HasBeenResolved, HasLocalType, IgnoreNoEffectAssignCheck, IgnoreRawTypeCheck, InsideJavadoc, INVOCATION_ARGUMENT_OK, INVOCATION_ARGUMENT_UNCHECKED, INVOCATION_ARGUMENT_WILDCARD, IsAnnotationDefaultValue, IsAnonymousType, IsAnySubRoutineEscaping, IsCompoundAssigned, IsDefaultConstructor, IsElseIfStatement, IsImplicitThis, IsImplicitUnit, IsLocalDeclarationReachable, IsLocalType, IsMemberType, IsNonNull, IsReachable, IsRecovered, IsReturnedValue, IsSecondaryType, IsStrictlyAssigned, IsSubRoutineEscaping, IsSuperType, IsSynchronized, IsTryBlockExiting, IsUsefulEmptyStatement, IsVarArgs, LabelUsed, NeededScope, NeedFreeReturn, OnDemand, OperatorMASK, OperatorSHIFT, OverridingMethodWithSupercall, ParenthesizedMASK, ParenthesizedSHIFT, RestrictiveFlagMASK, ReturnTypeIDMASK, sourceEnd, sourceStart, SuperAccess, ThenExit, UndocumentedEmptyBlock, UnnecessaryCast, UnsafeCast, Used

Fields inherited from interface org.eclipse.jdt.internal.compiler.ast.OperatorIds

AND, AND_AND, DIVIDE, EQUAL, EQUAL_EQUAL, GREATER, GREATER_EQUAL, INSTANCEOF, JML_ELEMTYPE, JML_EQUIV, JML_IMPLIES, JML_NONNULLELEMENTS, JML_NOT_ASSIGNED, JML_NOT_EQUIV, JML_NOT_MODIFIED, JML_OLD, JML_PRE, JML_REPRESENTS, JML_REV_IMPLIES, JML_TYPE, JML_TYPEOF, JmlOtherOpIdStart, LEFT_SHIFT, LESS, LESS_EQUAL, MINUS, MINUS_MINUS, MULTIPLY, NOT, NOT_EQUAL, NumberOfExtraTablesForJML, NumberOfTables, OR, OR_OR, PLUS, PLUS_PLUS, QUESTIONCOLON, REMAINDER, RIGHT_SHIFT, TWIDDLE, UNSIGNED_RIGHT_SHIFT, XOR

Fields inherited from interface org.eclipse.jdt.internal.compiler.lookup.TypeConstants

ANNOTATION, ANNOTATION_PREFIX, ANNOTATION_SUFFIX, ANONYM_PREFIX, ANONYM_SUFFIX, BOOLEAN, BYTE, CHAR, CharArray_JAVA_IO_OBJECTINPUTSTREAM, CharArray_JAVA_IO_OBJECTOUTPUTSTREAM, CharArray_JAVA_IO_OBJECTSTREAMFIELD, CharArray_JAVA_LANG_ANNOTATION_ANNOTATION, CharArray_JAVA_LANG_ENUM, CharArray_JAVA_LANG_OBJECT, CLINIT, CLONE, CONSTRAINT_EQUAL, CONSTRAINT_EXTENDS, CONSTRAINT_SUPER, DOUBLE, FLOAT, GETCLASS, INIT, INT, IO, JAVA, JAVA_IO, JAVA_IO_EXTERNALIZABLE, JAVA_IO_IOEXCEPTION, JAVA_IO_OBJECTINPUTSTREAM, JAVA_IO_OBJECTOUTPUTSTREAM, JAVA_IO_OBJECTSTREAMEXCEPTION, JAVA_IO_PRINTSTREAM, JAVA_IO_SERIALIZABLE, JAVA_LANG, JAVA_LANG_ANNOTATION_ANNOTATION, JAVA_LANG_ANNOTATION_DOCUMENTED, JAVA_LANG_ANNOTATION_ELEMENTTYPE, JAVA_LANG_ANNOTATION_INHERITED, JAVA_LANG_ANNOTATION_RETENTION, JAVA_LANG_ANNOTATION_RETENTIONPOLICY, JAVA_LANG_ANNOTATION_TARGET, JAVA_LANG_ASSERTIONERROR, JAVA_LANG_BOOLEAN, JAVA_LANG_BYTE, JAVA_LANG_CHARACTER, JAVA_LANG_CLASS, JAVA_LANG_CLASSNOTFOUNDEXCEPTION, JAVA_LANG_CLONEABLE, JAVA_LANG_DEPRECATED, JAVA_LANG_DOUBLE, JAVA_LANG_ENUM, JAVA_LANG_ERROR, JAVA_LANG_EXCEPTION, JAVA_LANG_FLOAT, JAVA_LANG_ILLEGALARGUMENTEXCEPTION, JAVA_LANG_INTEGER, JAVA_LANG_ITERABLE, JAVA_LANG_LONG, JAVA_LANG_NOCLASSDEFERROR, JAVA_LANG_OBJECT, JAVA_LANG_OVERRIDE, JAVA_LANG_REFLECT_CONSTRUCTOR, JAVA_LANG_REFLECT_FIELD, JAVA_LANG_REFLECT_METHOD, JAVA_LANG_RUNTIMEEXCEPTION, JAVA_LANG_SHORT, JAVA_LANG_STRING, JAVA_LANG_STRINGBUFFER, JAVA_LANG_STRINGBUILDER, JAVA_LANG_SUPPRESSWARNINGS, JAVA_LANG_SYSTEM, JAVA_LANG_THROWABLE, JAVA_LANG_VOID, JAVA_UTIL_ITERATOR, JML_ANNOTATION, JML_ANNOTATION_CODE_BIGINT_MATH, JML_ANNOTATION_CODE_JAVA_MATH, JML_ANNOTATION_CODE_SAFE_MATH, JML_ANNOTATION_GHOST, JML_ANNOTATION_HELPER, JML_ANNOTATION_INSTANCE, JML_ANNOTATION_MODEL, JML_ANNOTATION_NON_NULL, JML_ANNOTATION_NON_NULL_BY_DEFAULT, JML_ANNOTATION_NULLABLE, JML_ANNOTATION_NULLABLE_BY_DEFAULT, JML_ANNOTATION_PEER, JML_ANNOTATION_PKG, JML_ANNOTATION_PURE, JML_ANNOTATION_READONLY, JML_ANNOTATION_REP, JML_ANNOTATION_SPEC_BIGINT_MATH, JML_ANNOTATION_SPEC_JAVA_MATH, JML_ANNOTATION_SPEC_PROTECTED, JML_ANNOTATION_SPEC_PUBLIC, JML_ANNOTATION_SPEC_SAFE_MATH, JML_ANNOTATION_TYPE_CODE_BIGINT_MATH, JML_ANNOTATION_TYPE_CODE_JAVA_MATH, JML_ANNOTATION_TYPE_CODE_SAFE_MATH, JML_ANNOTATION_TYPE_GHOST, JML_ANNOTATION_TYPE_HELPER, JML_ANNOTATION_TYPE_INSTANCE, JML_ANNOTATION_TYPE_MODEL, JML_ANNOTATION_TYPE_NON_NULL_BY_DEFAULT, JML_ANNOTATION_TYPE_NONNULL, JML_ANNOTATION_TYPE_NULLABLE, JML_ANNOTATION_TYPE_NULLABLE_BY_DEFAULT, JML_ANNOTATION_TYPE_PEER, JML_ANNOTATION_TYPE_PURE, JML_ANNOTATION_TYPE_READONLY, JML_ANNOTATION_TYPE_REP, JML_ANNOTATION_TYPE_SPEC_BIGINT_MATH, JML_ANNOTATION_TYPE_SPEC_JAVA_MATH, JML_ANNOTATION_TYPE_SPEC_PROTECTED, JML_ANNOTATION_TYPE_SPEC_PUBLIC, JML_ANNOTATION_TYPE_SPEC_SAFE_MATH, JML_ANNOTATION_TYPE_UNINITIALIZED, JML_ANNOTATION_UNINITIALIZED, JML_ORG, JML_RUNTIME, JML_RUNTIME_ANNOTATION, JML4, JMLSPECS, LANG, LENGTH, LONG, MAIN, MISMATCH, NULL, OBJECT, OK, PACKAGE_INFO_NAME, READOBJECT, READRESOLVE, REFLECT, SERIALPERSISTENTFIELDS, SERIALVERSIONUID, SHORT, SYNTHETIC_ACCESS_METHOD_PREFIX, SYNTHETIC_ASSERT_DISABLED, SYNTHETIC_CLASS, SYNTHETIC_ENCLOSING_INSTANCE_PREFIX, SYNTHETIC_ENUM_VALUES, SYNTHETIC_OUTER_LOCAL_PREFIX, SYNTHETIC_SWITCH_ENUM_TABLE, TYPE, UNCHECKED, UPPER_ANNOTATION_TYPE, UPPER_CLASS, UPPER_CONSTRUCTOR, UPPER_FIELD, UPPER_LOCAL_VARIABLE, UPPER_METHOD, UPPER_PACKAGE, UPPER_PARAMETER, UPPER_RUNTIME, UPPER_SOURCE, UTIL, VALUE, VALUEOF, VALUES, VOID, WILDCARD_CAPTURE, WILDCARD_CAPTURE_NAME_PREFIX, WILDCARD_CAPTURE_NAME_SUFFIX, WILDCARD_EXTENDS, WILDCARD_MINUS, WILDCARD_NAME, WILDCARD_PLUS, WILDCARD_STAR, WILDCARD_SUPER, WRITEOBJECT, WRITEREPLACE

Fields inherited from interface org.eclipse.jdt.internal.compiler.lookup.TypeIds

Boolean2Boolean, Boolean2Int, Boolean2String, BOXING, Byte2Byte, Byte2Char, Byte2Double, Byte2Float, Byte2Int, Byte2Long, Byte2Short, Byte2String, Char2Byte, Char2Char, Char2Double, Char2Float, Char2Int, Char2Long, Char2Short, Char2String, COMPILE_TYPE_MASK, Double2Byte, Double2Char, Double2Double, Double2Float, Double2Int, Double2Long, Double2Short, Double2String, Float2Byte, Float2Char, Float2Double, Float2Float, Float2Int, Float2Long, Float2Short, Float2String, IMPLICIT_CONVERSION_MASK, Int2Byte, Int2Char, Int2Double, Int2Float, Int2Int, Int2Long, Int2Short, Int2String, Long2Byte, Long2Char, Long2Double, Long2Float, Long2Int, Long2Long, Long2Short, Long2String, NoId, Null2String, Object2Object, Object2String, Short2Byte, Short2Char, Short2Double, Short2Float, Short2Int, Short2Long, Short2Short, Short2String, String2String, T_boolean, T_byte, T_char, T_double, T_float, T_int, T_JavaIoException, T_JavaIoExternalizable, T_JavaIoObjectStreamException, T_JavaIoPrintStream, T_JavaIoSerializable, T_JavaLangAnnotationAnnotation, T_JavaLangAnnotationDocumented, T_JavaLangAnnotationElementType, T_JavaLangAnnotationInherited, T_JavaLangAnnotationRetention, T_JavaLangAnnotationRetentionPolicy, T_JavaLangAnnotationTarget, T_JavaLangAssertionError, T_JavaLangBoolean, T_JavaLangByte, T_JavaLangCharacter, T_JavaLangClass, T_JavaLangClassNotFoundException, T_JavaLangCloneable, T_JavaLangDeprecated, T_JavaLangDouble, T_JavaLangEnum, T_JavaLangError, T_JavaLangException, T_JavaLangFloat, T_JavaLangIllegalArgumentException, T_JavaLangInteger, T_JavaLangIterable, T_JavaLangLong, T_JavaLangNoClassDefError, T_JavaLangObject, T_JavaLangOverride, T_JavaLangReflectConstructor, T_JavaLangReflectField, T_JavaLangReflectMethod, T_JavaLangRuntimeException, T_JavaLangShort, T_JavaLangString, T_JavaLangStringBuffer, T_JavaLangStringBuilder, T_JavaLangSuppressWarnings, T_JavaLangSystem, T_JavaLangThrowable, T_JavaLangVoid, T_JavaUtilIterator, T_long, T_null, T_short, T_undefined, T_void, UNBOXING

Constructor Summary

CombinedBinaryExpression(CombinedBinaryExpression expression)

CombinedBinaryExpression(Expression left, Expression right, int operator, int arity)
Make a new CombinedBinaryExpression.

Method Summary

FlowInfo	analyseCode(BlockScope currentScope, FlowContext flowContext, FlowInfo flowInfo)
void	generateOptimizedStringConcatenation(BlockScope blockScope, CodeStream codeStream, int typeID)
void	generateOptimizedStringConcatenationCreation(BlockScope blockScope, CodeStream codeStream, int typeID)
java.lang.StringBuffer	printExpressionNoParenthesis(int indent, java.lang.StringBuffer output)
TypeBinding	resolveType(BlockScope scope) Resolve the type of this expression in the context of a blockScope
void	traverse(ASTVisitor visitor, BlockScope scope) Traverse an expression in the context of a blockScope
void	tuneArityMax() Change arityMax if and as needed.

Methods inherited from class org.eclipse.jdt.internal.compiler.ast.BinaryExpression

computeConstant, generateCode, generateLogicalAnd, generateLogicalOr, generateLogicalXor, generateOptimizedBoolean, generateOptimizedGreaterThan, generateOptimizedGreaterThanOrEqual, generateOptimizedLessThan, generateOptimizedLessThanOrEqual, generateOptimizedLogicalAnd, generateOptimizedLogicalOr, generateOptimizedLogicalXor, isCompactableOperation, optimizedBooleanConstant, optimizedBooleanConstant

Methods inherited from class org.eclipse.jdt.internal.compiler.ast.OperatorExpression

classInitialize, generateTableTestCase, get_AND_AND, get_AND, get_DIVIDE, get_EQUAL_EQUAL, get_GREATER_EQUAL, get_GREATER, get_LEFT_SHIFT, get_LESS_EQUAL, get_LESS, get_MINUS, get_MULTIPLY, get_OR_OR, get_OR, get_PLUS, get_REMAINDER, get_RIGHT_SHIFT, get_UNSIGNED_RIGHT_SHIFT, get_XOR, nullStatus, operatorToString, printExpression

Methods inherited from class org.eclipse.jdt.internal.compiler.ast.Expression

analyseCode, checkCastTypesCompatibility, checkNPE, checkUnsafeCast, computeConversion, generateCode, isConstantValueOfTypeAssignableToType, isConstantValueRepresentable, isDeclaredMonoNonNull, isDeclaredNonNull, isTypeReference, localVariableBinding, markAsNonNull, postConversionType, print, printStatement, resolve, resolveType, resolveTypeExpecting, reusableJSRTarget, setExpectedType, tagAsNeedCheckCast, tagAsUnnecessaryCast, toTypeReference, traverse

Methods inherited from class org.eclipse.jdt.internal.compiler.ast.Statement

branchChainTo, complainIfUnreachable, generateArguments, isEmptyBlock, isValidJavaStatement, resolveCase

Methods inherited from class org.eclipse.jdt.internal.compiler.ast.ASTNode

checkInvocationArguments, concreteStatement, isFieldUseDeprecated, isImplicitThis, isMethodUseDeprecated, isSuper, isThis, isTypeUseDeprecated, printAnnotations, printIndent, printModifiers, resolveAnnotations, resolveDeprecatedAnnotations, sourceEnd, sourceStart, toString

Methods inherited from class java.lang.Object

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

Field Detail

arity

public int arity

The number of consecutive binary expressions of this' left branch that bear the same operator as this.
Notes:

• the presence of a CombinedBinaryExpression instance resets arity, even when its operator is compatible;
• this property is maintained by the parser.

arityMax

public int arityMax

The threshold that will trigger the creation of the next full-fledged CombinedBinaryExpression. This field is only maintained for the topmost binary expression (it is 0 otherwise). It enables a variable policy, which scales better with very large expressions.

ARITY_MAX_MAX

public static final int ARITY_MAX_MAX

Upper limit for arityMax.

See Also:

Constant Field Values

ARITY_MAX_MIN

public static final int ARITY_MAX_MIN

Default lower limit for arityMax.

See Also:

Constant Field Values

defaultArityMaxStartingValue

public static int defaultArityMaxStartingValue

Default value for the first term of the series of arityMax values. Changing this allows for experimentation. Not meant to be changed during a parse operation.

referencesTable

public BinaryExpression[] referencesTable

A table of references to the binary expressions of this' left branch. Instances of CombinedBinaryExpression are not repeated here. Instead, the left subexpression of referencesTable[0] may be a combined binary expression, if appropriate. Null when this only cares about tracking the expression's arity.

Constructor Detail

CombinedBinaryExpression

public CombinedBinaryExpression(Expression left,
                                Expression right,
                                int operator,
                                int arity)

Make a new CombinedBinaryExpression. If arity is strictly greater than one, a references table is built and initialized with the reverse relationship of the one defined by BinaryExpression.left. arity and left must be compatible with each other (that is, there must be at least arity - 1 consecutive compatible binary expressions into the leftmost branch of left, the topmost of which being left's immediate left expression).

Parameters:

left - the left branch expression

right - the right branch expression

operator - the operator for this binary expression - only PLUS for now

arity - the number of binary expressions of a compatible operator that already exist into the leftmost branch of left (including left); must be strictly greater than 0

CombinedBinaryExpression

public CombinedBinaryExpression(CombinedBinaryExpression expression)

Method Detail

analyseCode

public FlowInfo analyseCode(BlockScope currentScope,
                            FlowContext flowContext,
                            FlowInfo flowInfo)

Overrides:

analyseCode in class BinaryExpression

generateOptimizedStringConcatenation

public void generateOptimizedStringConcatenation(BlockScope blockScope,
                                                 CodeStream codeStream,
                                                 int typeID)

Overrides:

generateOptimizedStringConcatenation in class BinaryExpression

generateOptimizedStringConcatenationCreation

public void generateOptimizedStringConcatenationCreation(BlockScope blockScope,
                                                         CodeStream codeStream,
                                                         int typeID)

Overrides:

generateOptimizedStringConcatenationCreation in class BinaryExpression

printExpressionNoParenthesis

public java.lang.StringBuffer printExpressionNoParenthesis(int indent,
                                                           java.lang.StringBuffer output)

Overrides:

printExpressionNoParenthesis in class BinaryExpression

resolveType

public TypeBinding resolveType(BlockScope scope)

Description copied from class: Expression

Resolve the type of this expression in the context of a blockScope

Overrides:

resolveType in class BinaryExpression

Returns:

Return the actual type of this expression after resolution

traverse

public void traverse(ASTVisitor visitor,
                     BlockScope scope)

Description copied from class: Expression

Traverse an expression in the context of a blockScope

Overrides:

traverse in class BinaryExpression

tuneArityMax

public void tuneArityMax()

Change arityMax if and as needed. The current policy is to double arityMax each time this method is called, until it reaches ARITY_MAX_MAX. Other policies may consider incrementing it less agressively. Call only after an appropriate value has been assigned to BinaryExpression.left.