edu.mit.ai.psg.jeva
Class TypeMethods

java.lang.Object
  |
  +--edu.mit.ai.psg.jeva.TypeMethods

public class TypeMethods

extends Object

Predicates and Methods for testing and comparing types. General type operations operate on type IClass, which includes both interpreted and wrapped compiled classes. Numeric type operations operaton only on type Class, since there are no interpreted numeric types.

Author:

CarlManning, caroma@ai.mit.edu
Copyright (c) 1997, 1998, 1999 Massachusetts Institute of Technology

Field Summary

static IClass	booleanIClass
static IClass	byteIClass
static IClass	charIClass
static IClass	ClassIClass
static IClass	CloneableIClass
static IClass	doubleIClass
static IClass	ErrorIClass
static IClass	floatIClass
static IClass	intIClass
static IClass	longIClass
static IClass	NumberIClass
static IClass	ObjectIClass
static IClass	RuntimeExceptionIClass
static IClass	shortIClass
static IClass	StringIClass
static IClass	ThrowableIClass
static IClass	voidIClass

Constructor Summary

TypeMethods()

Method Summary

static IClass	binaryCombineBitwiseTypes(Token operator, IClass cX, IClass cY)
static IClass	binaryCombineNumericTypes(Token operator, IClass cX, IClass cY)
static IClass	binaryCombineShiftTypes(Token operator, IClass leftType, IClass rightType)
static Class	binaryPromoteType(Class cX, Class cY) [JavaLangSpec1.0 sec 5.6.2 Binary Numeric Promotion]
static boolean	canNarrowPrimitive(Class to, Class from) [JavaLangSpec1.0 sec 5.1.3 Narrowing Primitive Conversions]
static boolean	canNarrowPrimitiveConstant(Class receivingType, Class exprType, IExpressionNode expr, IEnv env) [JavaLangSpec1.0 sec 5.2, 15.24] check if expr is integer constant that fits in char, short, or byte.
static boolean	canNarrowReference(IClass to, IClass from) [JavaLangSpec1.0 sec 5.1.5 Narrowing Reference Conversions] Uses i.isAssignableFrom(c) to test c implements interface i
static boolean	canWidenPrimitive(Class to, Class from) [JavaLangSpec1.0 sec 5.1.2 Widening Primitive Conversions]
static boolean	canWidenPrimitive(IClass to, IClass from)
static boolean	canWidenReference(Class to, Class from) [JavaLangSpec1.0 sec 5.1.4 Widening Reference Conversions] null used as class of null, can be assigned to any Reference type, so more general than to.isAssignableFrom(from)
static boolean	canWidenReference(IClass to, IClass from) implements isAssignableFrom for interpreted classes by searching
static void	checkCastTypes(IClass castType, IClass exprType) check for impermissible casts.
static IClass	getIClass(Object obj) get IClass for implementation class of object
static boolean	isAbstractClass(IClass aClass)
static boolean	isApplicable(IClass[] parameterTypes, IClass[] argExprTypes)
static boolean	isApplicable(IConstructor constructor, IClass[] argExprTypes)
static boolean	isApplicable(IMethod method, IClass[] argExprTypes) [JavaLangSpec 15.11.2.1 Find Methods that are applicable (& accessible)] Accessibility is not a concern, since only public methods are accessible through reflection (not necessarily true in Java1.2).
static boolean	isAssignable(IClass receivingIClass, IExpressionNode expr, IEnv env)
static boolean	isAssignableType(Class receivingType, Class exprType, IExpressionNode expr, IEnv env) [JavaLangSpec1.0 sec 5.2 Assignment Conversion] This checks for primitive as well as reference widenings.
static boolean	isBindableType(Class receivingType, Class exprType) [JavaLangSpec1.0 sec 5.3 Method Invocation Conversion]
static boolean	isBindableType(IClass receivingIClass, IClass exprIClass)
static boolean	isCaughtOrDeclaredException(IClass exceptionClass, IClass[] caughtOrDeclareds)
static boolean	isClassType(IClass type)
static boolean	isFinalClass(IClass aClass)
static boolean	isImplementation(IClass sub, IClass anInterface)
static boolean	isIntegralType(Class type)
static boolean	isIntegralType(IClass type)
static boolean	isIntExpression(IExpressionNode expr, IEnv env) Check that array dims/indexes are int [JavaLangSpec1.0 sec15.9, 15.12]
static boolean	isMoreSpecific(IConstructor c1, IConstructor c2)
static boolean	isMoreSpecific(IMethod m1, IMethod m2) [JavaLangSpec 15.11.2.2 Choose Most Specific Method] assumes method name matches
static boolean	isNumericType(Class type)
static boolean	isNumericType(IClass type)
static boolean	isReferenceType(Class type)
static boolean	isReferenceType(IClass type)
static boolean	isSubclass(IClass sub, IClass aSuper)
static boolean	isSubinterface(IClass sub, IClass aSuper)
static boolean	isUncheckedException(IClass exceptionClass)
static IClass	makeArrayType(IClass baseType, int nDims)
static IClass	nameToPrimitiveIClass(String name)
static Class	nameToPrimitiveType(String name)
static IClass	toPrimitiveIClass(IClass wrapperType)
static Class	toPrimitiveType(Class wrapperType)
static String	toSourceString(Class type)
static String	toSourceString(IClass type) Return source code declaration string for class even if it is an array, e.g., "int[][]" instead of "[[I", which is what type.getName() returns
static Class	unaryPromoteType(Class type) [JavaLangSpec1.0 sec 5.6.1 Unary Numeric Promotion]
static IClass	unaryPromoteType(IClass type)

Methods inherited from class java.lang.Object

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

Field Detail

ObjectIClass

public static final IClass ObjectIClass

ClassIClass

public static final IClass ClassIClass

StringIClass

public static final IClass StringIClass

CloneableIClass

public static final IClass CloneableIClass

NumberIClass

public static final IClass NumberIClass

booleanIClass

public static final IClass booleanIClass

intIClass

public static final IClass intIClass

longIClass

public static final IClass longIClass

doubleIClass

public static final IClass doubleIClass

floatIClass

public static final IClass floatIClass

charIClass

public static final IClass charIClass

byteIClass

public static final IClass byteIClass

shortIClass

public static final IClass shortIClass

voidIClass

public static final IClass voidIClass

ThrowableIClass

public static final IClass ThrowableIClass

ErrorIClass

public static final IClass ErrorIClass

RuntimeExceptionIClass

public static final IClass RuntimeExceptionIClass

Constructor Detail

TypeMethods

public TypeMethods()

Method Detail

isReferenceType

public static final boolean isReferenceType(Class type)

isReferenceType

public static final boolean isReferenceType(IClass type)

isClassType

public static final boolean isClassType(IClass type)

isNumericType

public static final boolean isNumericType(Class type)

isNumericType

public static final boolean isNumericType(IClass type)

isIntegralType

public static final boolean isIntegralType(Class type)

isIntegralType

public static final boolean isIntegralType(IClass type)

unaryPromoteType

public static final Class unaryPromoteType(Class type)

[JavaLangSpec1.0 sec 5.6.1 Unary Numeric Promotion]

unaryPromoteType

public static final IClass unaryPromoteType(IClass type)

binaryPromoteType

public static final Class binaryPromoteType(Class cX,
                                            Class cY)

[JavaLangSpec1.0 sec 5.6.2 Binary Numeric Promotion]

binaryCombineNumericTypes

public static final IClass binaryCombineNumericTypes(Token operator,
                                                     IClass cX,
                                                     IClass cY)

Throws:

IllegalArgumentException - if given non-numeric type

binaryCombineBitwiseTypes

public static final IClass binaryCombineBitwiseTypes(Token operator,
                                                     IClass cX,
                                                     IClass cY)

Throws:

IllegalArgumentException - if given non-numeric non-boolean type

binaryCombineShiftTypes

public static final IClass binaryCombineShiftTypes(Token operator,
                                                   IClass leftType,
                                                   IClass rightType)

Throws:

IllegalArgumentException - if given non-integral types

isAssignableType

public static final boolean isAssignableType(Class receivingType,
                                             Class exprType,
                                             IExpressionNode expr,
                                             IEnv env)
                                      throws VerifyingException

[JavaLangSpec1.0 sec 5.2 Assignment Conversion] This checks for primitive as well as reference widenings.

isAssignable

public static final boolean isAssignable(IClass receivingIClass,
                                         IExpressionNode expr,
                                         IEnv env)
                                  throws VerifyingException

isBindableType

public static final boolean isBindableType(Class receivingType,
                                           Class exprType)

[JavaLangSpec1.0 sec 5.3 Method Invocation Conversion]

isBindableType

public static final boolean isBindableType(IClass receivingIClass,
                                           IClass exprIClass)

canWidenPrimitive

public static final boolean canWidenPrimitive(Class to,
                                              Class from)

[JavaLangSpec1.0 sec 5.1.2 Widening Primitive Conversions]

canWidenPrimitive

public static final boolean canWidenPrimitive(IClass to,
                                              IClass from)

canNarrowPrimitiveConstant

public static final boolean canNarrowPrimitiveConstant(Class receivingType,
                                                       Class exprType,
                                                       IExpressionNode expr,
                                                       IEnv env)
                                                throws VerifyingException

[JavaLangSpec1.0 sec 5.2, 15.24] check if expr is integer constant that fits in char, short, or byte.

canNarrowPrimitive

public static final boolean canNarrowPrimitive(Class to,
                                               Class from)

[JavaLangSpec1.0 sec 5.1.3 Narrowing Primitive Conversions]

canWidenReference

public static final boolean canWidenReference(Class to,
                                              Class from)

[JavaLangSpec1.0 sec 5.1.4 Widening Reference Conversions] null used as class of null, can be assigned to any Reference type, so more general than to.isAssignableFrom(from)

canWidenReference

public static final boolean canWidenReference(IClass to,
                                              IClass from)

implements isAssignableFrom for interpreted classes by searching

isFinalClass

public static final boolean isFinalClass(IClass aClass)

isAbstractClass

public static final boolean isAbstractClass(IClass aClass)

isSubinterface

public static final boolean isSubinterface(IClass sub,
                                           IClass aSuper)

isSubclass

public static final boolean isSubclass(IClass sub,
                                       IClass aSuper)

isImplementation

public static final boolean isImplementation(IClass sub,
                                             IClass anInterface)

canNarrowReference

public static final boolean canNarrowReference(IClass to,
                                               IClass from)

[JavaLangSpec1.0 sec 5.1.5 Narrowing Reference Conversions] Uses i.isAssignableFrom(c) to test c implements interface i

toPrimitiveType

public static final Class toPrimitiveType(Class wrapperType)

toPrimitiveIClass

public static final IClass toPrimitiveIClass(IClass wrapperType)

nameToPrimitiveType

public static final Class nameToPrimitiveType(String name)
                                       throws ClassNotFoundException

nameToPrimitiveIClass

public static final IClass nameToPrimitiveIClass(String name)
                                          throws ClassNotFoundException

toSourceString

public static final String toSourceString(IClass type)

Return source code declaration string for class even if it is an array, e.g., "int[][]" instead of "[[I", which is what type.getName() returns

toSourceString

public static final String toSourceString(Class type)

makeArrayType

public static final IClass makeArrayType(IClass baseType,
                                         int nDims)

checkCastTypes

public static final void checkCastTypes(IClass castType,
                                        IClass exprType)

check for impermissible casts. [JavaLangSpec1.0 sec 5.4 Casting Conversion] Throws ClassCastException if a check fails. Many type mismatches are compile time errors, not runtime errors, so caller may want to catch the ClassCastException and throw an IllegalTypeException instead.

isApplicable

public static final boolean isApplicable(IMethod method,
                                         IClass[] argExprTypes)

[JavaLangSpec 15.11.2.1 Find Methods that are applicable (& accessible)] Accessibility is not a concern, since only public methods are accessible through reflection (not necessarily true in Java1.2).

isApplicable

public static final boolean isApplicable(IConstructor constructor,
                                         IClass[] argExprTypes)

isApplicable

public static final boolean isApplicable(IClass[] parameterTypes,
                                         IClass[] argExprTypes)

isMoreSpecific

public static final boolean isMoreSpecific(IMethod m1,
                                           IMethod m2)

[JavaLangSpec 15.11.2.2 Choose Most Specific Method] assumes method name matches

isMoreSpecific

public static final boolean isMoreSpecific(IConstructor c1,
                                           IConstructor c2)

isIntExpression

public static final boolean isIntExpression(IExpressionNode expr,
                                            IEnv env)
                                     throws VerifyingException

Check that array dims/indexes are int [JavaLangSpec1.0 sec15.9, 15.12]

isUncheckedException

public static boolean isUncheckedException(IClass exceptionClass)

isCaughtOrDeclaredException

public static boolean isCaughtOrDeclaredException(IClass exceptionClass,
                                                  IClass[] caughtOrDeclareds)

getIClass

public static IClass getIClass(Object obj)

get IClass for implementation class of object