net.sf.saxon.value

Class IntegerRange

public class IntegerRange extends Value implements 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
longend
longstart
Constructor Summary
IntegerRange(long start, long end)
Construct an integer range expression
Method Summary
intgetCardinality()
Determine the cardinality
longgetEnd()
Get the last integer in the sequence (inclusive)
ItemTypegetItemType(TypeHierarchy th)
Determine the data type of the items in the expression, if possible
intgetLength()
Get the length of the sequence
longgetStart()
Get the first integer in the sequence (inclusive)
ItemitemAt(int n)
Get the n'th item in the sequence (starting from 0).
SequenceIteratoriterate()
Return an Iterator to iterate over the values of a sequence.
GroundedValuesubsequence(int start, int length)
Get a subsequence of the value

Field Detail

end

public long end

start

public long start

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

getCardinality

public int getCardinality()
Determine the cardinality

getEnd

public long getEnd()
Get the last integer in the sequence (inclusive)

Returns: the last integer in the sequence (inclusive)

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)

getLength

public int getLength()
Get the length of the sequence

getStart

public long getStart()
Get the first integer in the sequence (inclusive)

Returns: the first integer in the sequence (inclusive)

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()
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.

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

subsequence

public GroundedValue subsequence(int start, int length)
Get a subsequence of the value

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.