gnu.kawa.reflect

Class OccurrenceType

Implemented Interfaces:
Externalizable, TypeValue
Known Direct Subclasses:
NodeSetType

public class OccurrenceType
extends ObjectType
implements Externalizable, TypeValue

A type that matches some number of repetitions of a basetype.

Field Summary

static Type
emptySequenceType
static ClassType
typeOccurrenceType

Fields inherited from class gnu.bytecode.ObjectType

flags

Fields inherited from class gnu.bytecode.Type

booleanValue_method, boolean_ctype, boolean_type, byte_type, char_type, clone_method, doubleValue_method, double_type, floatValue_method, float_type, intValue_method, int_type, java_lang_Class_type, longValue_method, long_type, neverReturnsType, nullType, number_type, pointer_type, reflectClass, short_type, string_type, throwable_type, toString_method, tostring_type, typeArray0, void_type

Constructor Summary

OccurrenceType(Type base, int minOccurs, int maxOccurs)

Method Summary

Object
coerceFromObject(Object obj)
Convert an object to a value of this Type.
int
compare(Type other)
Return a numeric code showing "subtype" relationship: 1: if other is a pure subtype of this; 0: if has the same values; -1: if this is a pure subtype of other; -2: if they have values in common but neither is a subtype of the other; -3: if the types have no values in common.
void
emitIsInstance(Variable incoming, Compilation comp, Target target)
void
emitTestIf(Variable incoming, Declaration decl, Compilation comp)
Type
getBase()
Procedure
getConstructor()
Type
getImplementationType()
The type used to implement types not natively understood by the JVM.
static Type
getInstance(Type base, int minOccurs, int maxOccurs)
boolean
isInstance(Object obj)
static char
itemCountCode(Type type)
Returna a quantifer kind for a sequence type.
static boolean
itemCountIsOne(Type type)
static boolean
itemCountIsZeroOrOne(Type type)
static int
itemCountRange(Type type)
Return a conservative estimage on the min/max number of items of a type.
static Type
itemPrimeType(Type type)
QUery formal semantics "prime type"
int
maxOccurs()
int
minOccurs()
void
readExternal(ObjectInput in)
String
toString()
void
writeExternal(ObjectOutput out)

Methods inherited from class gnu.bytecode.ObjectType

coerceFromObject, compare, emitCoerceFromObject, getContextClass, getImplementationType, getInternalName, getMethods, getReflectClass, isExisting, isInstance, promote, setExisting

Methods inherited from class gnu.bytecode.Type

coerceFromObject, coerceToObject, compare, emitCoerceFromObject, emitCoerceToObject, emitIsInstance, getImplementationType, getName, getReflectClass, getSignature, getSize, getSizeInWords, getType, hashCode, isInstance, isMoreSpecific, isSubtype, isValidJavaTypeName, isVoid, lookupType, lowestCommonSuperType, make, promote, registerTypeForClass, setName, setReflectClass, setSignature, signatureLength, signatureLength, signatureToName, signatureToPrimitive, signatureToType, signatureToType, swappedCompareResult, toString

Field Details

emptySequenceType

public static final Type emptySequenceType

typeOccurrenceType

public static final ClassType typeOccurrenceType

Constructor Details

OccurrenceType

public OccurrenceType(Type base,
                      int minOccurs,
                      int maxOccurs)

Method Details

coerceFromObject

public Object coerceFromObject(Object obj)
Convert an object to a value of this Type. Throw a ClassCastException when this is not possible.
Overrides:
coerceFromObject in interface ObjectType

compare

public int compare(Type other)
Return a numeric code showing "subtype" relationship: 1: if other is a pure subtype of this; 0: if has the same values; -1: if this is a pure subtype of other; -2: if they have values in common but neither is a subtype of the other; -3: if the types have no values in common. "Same member" is rather loose; by "A is a subtype of B" we mean that all instance of A can be "widened" to B. More formally, A.compare(B) returns: 1: all B values can be converted to A without a coercion failure (i.e. a ClassCastException or overflow or major loss of information), but not vice versa. 0: all A values can be converted to B without a coercion failure and vice versa; -1: all A values can be converted to B without a coercion failure not not vice versa; -2: there are (potentially) some A values that can be converted to B, and some B values can be converted to A; -3: there are no A values that can be converted to B, and neither are there any B values that can be converted to A.
Overrides:
compare in interface ObjectType

emitIsInstance

public void emitIsInstance(Variable incoming,
                           Compilation comp,
                           Target target)
Specified by:
emitIsInstance in interface TypeValue

emitTestIf

public void emitTestIf(Variable incoming,
                       Declaration decl,
                       Compilation comp)
Specified by:
emitTestIf in interface TypeValue

getBase

public Type getBase()

getConstructor

public Procedure getConstructor()
Specified by:
getConstructor in interface TypeValue

getImplementationType

public Type getImplementationType()
The type used to implement types not natively understood by the JVM. Usually, the identity function. However, a language might handle union types or template types or type expressions calculated at run time. In that case return the type used at the JVM level, and known at compile time.
Specified by:
getImplementationType in interface TypeValue
Overrides:
getImplementationType in interface ObjectType

getInstance

public static Type getInstance(Type base,
                               int minOccurs,
                               int maxOccurs)

isInstance

public boolean isInstance(Object obj)
Overrides:
isInstance in interface ObjectType

itemCountCode

public static char itemCountCode(Type type)
Returna a quantifer kind for a sequence type.
Returns:
'0' if type is known to be a void (0-item) type; '1' if type is known to be a single-item type; '?' if type matches a sequence of 0 or 1 items; '+' if type matches a sequence of 1 or more items; '*' otherwise.

itemCountIsOne

public static boolean itemCountIsOne(Type type)

itemCountIsZeroOrOne

public static boolean itemCountIsZeroOrOne(Type type)

itemCountRange

public static int itemCountRange(Type type)
Return a conservative estimage on the min/max number of items of a type.
Returns:
maxCount << 12 | minCount & 0xFFF, where a maxCount of -1 means unbounded.

itemPrimeType

public static Type itemPrimeType(Type type)
QUery formal semantics "prime type"

maxOccurs

public int maxOccurs()

minOccurs

public int minOccurs()

readExternal

public void readExternal(ObjectInput in)
            throws IOException,
                   ClassNotFoundException

toString

public String toString()
Overrides:
toString in interface Type

writeExternal

public void writeExternal(ObjectOutput out)
            throws IOException