net.sf.saxon.value

Class IntegerRange

public class IntegerRange extends Value

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
long	end
long	start

Constructor Summary
	IntegerRange(long start, long end)

Method Summary
void	display(int level, NamePool pool, PrintStream out) Diagnostic display of the expression
int	getCardinality() Determine the cardinality
long	getEnd()
int	getImplementationMethod() An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process().
ItemType	getItemType(TypeHierarchy th) Determine the data type of the items in the expression, if possible
int	getLength() Get the length of the sequence
long	getStart()
Item	itemAt(int n) Get the n'th item in the sequence (starting from 0).
SequenceIterator	iterate(XPathContext context) Return an Iterator to iterate over the values of a sequence.

Constructor Detail

IntegerRange

public IntegerRange(long start, long end)

Method Detail

display

public void display(int level, NamePool pool, PrintStream out)

Diagnostic display of the expression

getCardinality

public int getCardinality()

Determine the cardinality

An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process(). This method indicates which of these methods is provided directly. The other methods will always be available indirectly, using an implementation that relies on one of the other methods.

getItemType

public ItemType getItemType(TypeHierarchy th)

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

Parameters: th

Returns: AnyItemType (not known)

getLength

public int getLength()

Get the length of the sequence

getStart

public long getStart()

itemAt

public Item 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)

iterate

public SequenceIterator iterate(XPathContext context)

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.

Parameters: context supplies the context for evaluation

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

Throws: net.sf.saxon.trans.XPathException if any dynamic error occurs evaluating the expression