public class SingletonItem<T extends Item> extends Value<T> implements GroundedValue<T>
Modifier and Type | Field and Description |
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protected T |
item |
INDETERMINATE_ORDERING
EMPTY_VALUE_ARRAY
Constructor and Description |
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SingletonItem(T item)
Create a node-set containing zero or one nodes
|
Modifier and Type | Method and Description |
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T |
asItem()
Return the value in the form of an Item
|
boolean |
effectiveBooleanValue()
Get the effective boolean value
|
int |
getCardinality()
Determine the static cardinality
|
ItemType |
getItemType(TypeHierarchy th)
Determine the data type of the items in the expression.
|
int |
getLength()
Get the length of the sequence
|
String |
getStringValue()
Convert the value to a string, using the serialization rules.
|
T |
itemAt(int n)
Get the n'th item in the sequence (starting from 0).
|
SequenceIterator<T> |
iterate()
Return an enumeration of this nodeset value.
|
void |
process(XPathContext context)
Process the instruction, without returning any tail calls
|
GroundedValue<T> |
subsequence(int start,
int length)
Get a subsequence of the value
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asItem, asIterator, asValue, checkPermittedContents, convertToJava, equals, fromItem, getCanonicalLexicalRepresentation, getIterator, getSchemaComparable, getSequenceLength, getStringValueCS, hashCode, isIdentical, reduce
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait
getStringValueCS
public SingletonItem(T item)
item
- The node or function-item to be contained in the node-set, or null if the sequence
is to be emptypublic T asItem()
public void process(XPathContext context) throws XPathException
process
in class Value<T extends Item>
context
- The dynamic context, giving access to the current node,
the current variables, etc.XPathException
- if an error occurs (for example if the value is
a closure that needs to be evaluated)public ItemType getItemType(TypeHierarchy th)
getItemType
in class Value<T extends Item>
th
- the type hierarchy cachepublic int getCardinality()
getCardinality
in class Value<T extends Item>
public int getLength()
public T itemAt(int n)
itemAt
in interface GroundedValue<T extends Item>
itemAt
in class Value<T extends Item>
n
- position of the required item, counting from zero.public GroundedValue<T> subsequence(int start, int length)
subsequence
in interface GroundedValue<T extends Item>
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 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 sequencepublic SequenceIterator<T> iterate()
public boolean effectiveBooleanValue()
effectiveBooleanValue
in class Value<T extends Item>
public String getStringValue()
getStringValue
in interface ValueRepresentation<T extends Item>
getStringValue
in class Value<T extends Item>