net.sf.saxon.value

Class IntegerRange

java.lang.Object

net.sf.saxon.value.IntegerRange

All Implemented Interfaces:

AtomicSequence, GroundedValue, Sequence

public class IntegerRange
extends Object
implements AtomicSequence, GroundedValue

This class represents a sequence of consecutive ascending integers, for example 1 to 50. The integers must be within the range of a Java long.

Field Summary

Fields

Modifier and Type	Field and Description
long	end
long	start

Constructor Summary

Constructors

Constructor and Description
IntegerRange(long start, long end) Construct an integer range expression

Method Summary

Methods

Modifier and Type	Method and Description
boolean	effectiveBooleanValue() Get the effective boolean value of this sequence
CharSequence	getCanonicalLexicalRepresentation() Get the canonical lexical representation as defined in XML Schema.
int	getCardinality() Determine the cardinality
long	getEnd() Get the last integer in the sequence (inclusive)
ItemType	getItemType(TypeHierarchy th) Determine the data type of the items in the expression, if possible
int	getLength() Get the length of the sequence
Comparable	getSchemaComparable() Get a Comparable value that implements the XML Schema ordering comparison semantics for this value.
long	getStart() Get the first integer in the sequence (inclusive)
String	getStringValue() Get the string value of this sequence.
CharSequence	getStringValueCS() Get the string value of this sequence.
AtomicValue	head() Get the first item in the sequence.
IntegerValue	itemAt(int n) Get the n'th item in the sequence (starting from 0).
SequenceIterator<IntegerValue>	iterate() Return an Iterator to iterate over the values of a sequence.
GroundedValue	reduce() Reduce the sequence to its simplest form.
GroundedValue	subsequence(int start, int length) Get a subsequence of the value

Methods inherited from class java.lang.Object

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

Field Detail

start

public long start

end

public long end

Constructor Detail

IntegerRange

public IntegerRange(long start,
            long end)

Construct an integer range expression

Parameters:

start - the first integer in the sequence (inclusive)

end - the last integer in the sequence (inclusive). Must be >= start

Method Detail

getStart

public long getStart()

Get the first integer in the sequence (inclusive)

Returns:

the first integer in the sequence (inclusive)

getEnd

public long getEnd()

Get the last integer in the sequence (inclusive)

Returns:

the last integer in the sequence (inclusive)

iterate

public SequenceIterator<IntegerValue> iterate()

Return an Iterator to iterate over the values of a sequence. The value of every expression can be regarded as a sequence, so this method is supported for all expressions. This default implementation handles iteration for expressions that return singleton values: for non-singleton expressions, the subclass must provide its own implementation.

Specified by:

iterate in interface AtomicSequence

Specified by:

iterate in interface Sequence

Returns:

a SequenceIterator that can be used to iterate over the result of the expression

Throws:

XPathException - if any dynamic error occurs evaluating the expression

getItemType

public ItemType getItemType(TypeHierarchy th)

Determine the data type of the items in the expression, if possible

Parameters:

th - the type hierarchy cache

Returns:

AnyItemType (not known)

getCardinality

public int getCardinality()

Determine the cardinality

itemAt

public IntegerValue itemAt(int n)

Get the n'th item in the sequence (starting from 0). This is defined for all Values, but its real benefits come for a sequence Value stored extensionally (or for a MemoClosure, once all the values have been read)

Specified by:

itemAt in interface AtomicSequence

Specified by:

itemAt in interface GroundedValue

Parameters:

n - the index of the required item, with 0 representing the first item in the sequence

Returns:

the n'th item if it exists, or null otherwise

subsequence

public GroundedValue subsequence(int start,
                        int length)

Get a subsequence of the value

Specified by:

subsequence in interface GroundedValue

Parameters:

start - the index of the first item to be included in the result, counting from zero. A negative value is taken as zero. If the value is beyond the end of the sequence, an empty sequence is returned

length - the number of items to be included in the result. Specify Integer.MAX_VALUE to get the subsequence up to the end of the base sequence. If the value is negative, an empty sequence is returned. If the value goes off the end of the sequence, the result returns items up to the end of the sequence

Returns:

the required subsequence.

getLength

public int getLength()

Get the length of the sequence

Specified by:

getLength in interface AtomicSequence

Specified by:

getLength in interface GroundedValue

Returns:

the number of items in the sequence

head

public AtomicValue head()

Description copied from interface: Sequence

Get the first item in the sequence.

Specified by:

head in interface AtomicSequence

Specified by:

head in interface Sequence

Returns:

the first item in the sequence if there is one, or null if the sequence is empty

getCanonicalLexicalRepresentation

public CharSequence getCanonicalLexicalRepresentation()

Get the canonical lexical representation as defined in XML Schema. This is not always the same as the result of casting to a string according to the XPath rules.

Specified by:

getCanonicalLexicalRepresentation in interface AtomicSequence

Returns:

the canonical lexical representation if defined in XML Schema; otherwise, the result of casting to string according to the XPath 2.0 rules

getSchemaComparable

public Comparable getSchemaComparable()

Get a Comparable value that implements the XML Schema ordering comparison semantics for this value. The default implementation is written to compare sequences of atomic values. This method is overridden for AtomicValue and its subclasses.

In the case of data types that are partially ordered, the returned Comparable extends the standard semantics of the compareTo() method by returning the value SequenceTool.INDETERMINATE_ORDERING when there is no defined order relationship between two given values.

Specified by:

getSchemaComparable in interface AtomicSequence

Returns:

a Comparable that follows XML Schema comparison rules

getStringValueCS

public CharSequence getStringValueCS()

Description copied from interface: GroundedValue

Get the string value of this sequence. The string value of an item is the result of applying the string() function. The string value of a sequence is the space-separated result of applying the string-join() function using a single space as the separator

Specified by:

getStringValueCS in interface AtomicSequence

Specified by:

getStringValueCS in interface GroundedValue

Returns:

the string value of the sequence.

getStringValue

public String getStringValue()

Description copied from interface: GroundedValue

Get the string value of this sequence. The string value of an item is the result of applying the string() function. The string value of a sequence is the space-separated result of applying the string-join() function using a single space as the separator

Specified by:

getStringValue in interface AtomicSequence

Specified by:

getStringValue in interface GroundedValue

Returns:

the string value of the sequence.

effectiveBooleanValue

public boolean effectiveBooleanValue()
                              throws XPathException

Description copied from interface: GroundedValue

Get the effective boolean value of this sequence

Specified by:

effectiveBooleanValue in interface GroundedValue

Returns:

the effective boolean value

Throws:

XPathException - if the sequence has no effective boolean value (for example a sequence of two integers)

reduce

public GroundedValue reduce()

Reduce the sequence to its simplest form. If the value is an empty sequence, the result will be EmptySequence.getInstance(). If the value is a single atomic value, the result will be an instance of AtomicValue. If the value is a single item of any other kind, the result will be an instance of SingletonItem. Otherwise, the result will typically be unchanged.

Specified by:

reduce in interface GroundedValue

Returns:

the simplified sequence