net.sf.saxon.value
Class EmptySequence
- GroundedValue, Serializable, SequenceIterable, ValueRepresentation
public final class EmptySequence
An EmptySequence object represents a sequence containing no members.
asItem , asItem , asIterator , asValue , checkPermittedContents , convertJavaObjectToXPath , convertToJava , convertToJava , effectiveBooleanValue , equals , fromItem , getCanonicalLexicalRepresentation , getCardinality , getItemType , getIterator , getLength , getSchemaComparable , getStringValue , getStringValueCS , itemAt , iterate , iterate , makeQNameValue , process , reduce , stringToNumber , toString |
asItem
public Item asItem()
Return the value in the form of an Item
- asItem in interface Value
- the value in the form of an Item
effectiveBooleanValue
public boolean effectiveBooleanValue()
Get the effective boolean value - always false
- effectiveBooleanValue in interface Value
equals
public boolean equals(Object other)
Is this expression the same as another expression?
- equals in interface Value
getCardinality
public int getCardinality()
Determine the static cardinality
- getCardinality in interface Value
getInstance
public static EmptySequence getInstance()
Get the implicit instance of this class
getLength
public final int getLength()
Get the length of the sequence
- getLength in interface Value
- always 0 for an empty sequence
hashCode
public int hashCode()
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)
- itemAt in interface GroundedValue
- itemAt in interface Value
n
- position of the required item, counting from zero.
- the n'th item in the sequence, where the first item in the sequence is
numbered zero. If n is negative or >= the length of the sequence, returns null.
subsequence
public GroundedValue subsequence(int min,
int length)
Get a subsequence of the value
- subsequence in interface GroundedValue
min
- 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 returnedlength
- 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
- the required subsequence. If min is