net.sf.saxon.type
Class TypeHierarchy

java.lang.Object
  net.sf.saxon.type.TypeHierarchy

All Implemented Interfaces:

java.io.Serializable

public class TypeHierarchy

extends java.lang.Object

implements java.io.Serializable

This class exists to provide answers to questions about the type hierarchy. Because such questions are potentially expensive, it caches the answers.

See Also:

Serialized Form

Field Summary

static int	DISJOINT Constant denoting relationship between two types: A is disjoint from B
static int	OVERLAPS Constant denoting relationship between two types: A overlaps B
static int	SAME_TYPE Constant denoting relationship between two types: A is the same type as B
static int	SUBSUMED_BY Constant denoting relationship between two types: A is subsumed by B
static int	SUBSUMES Constant denoting relationship between two types: A subsumes B

Constructor Summary

TypeHierarchy()

Method Summary

boolean	isSubType(ItemType subtype, ItemType supertype) Determine whether type A is type B or one of its subtypes, recursively
int	relationship(ItemType t1, ItemType t2) Determine the relationship of one item type to another.

Methods inherited from class java.lang.Object

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

Field Detail

SAME_TYPE

public static final int SAME_TYPE

Constant denoting relationship between two types: A is the same type as B

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Constant Field Values

SUBSUMES

public static final int SUBSUMES

Constant denoting relationship between two types: A subsumes B

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Constant Field Values

SUBSUMED_BY

public static final int SUBSUMED_BY

Constant denoting relationship between two types: A is subsumed by B

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Constant Field Values

OVERLAPS

public static final int OVERLAPS

Constant denoting relationship between two types: A overlaps B

See Also:

Constant Field Values

DISJOINT

public static final int DISJOINT

Constant denoting relationship between two types: A is disjoint from B

See Also:

Constant Field Values

Constructor Detail

TypeHierarchy

public TypeHierarchy()

Method Detail

isSubType

public boolean isSubType(ItemType subtype,
                         ItemType supertype)

Determine whether type A is type B or one of its subtypes, recursively

Parameters:

subtype - identifies the first type

supertype - identifies the second type

Returns:

true if the first type is the second type or a (direct or indirect) subtype of the second type

relationship

public int relationship(ItemType t1,
                        ItemType t2)

Determine the relationship of one item type to another.

Parameters:

t1 - the first item type

t2 - the second item type

Returns:

SAME_TYPE if the types are the same; SUBSUMES if the first type subsumes the second (that is, all instances of the second type are also instances of the first); SUBSUMED_BY if the second type subsumes the first; OVERLAPS if the two types overlap (have a non-empty intersection, but neither subsumes the other); DISJOINT if the two types are disjoint (have an empty intersection)