net.sf.saxon.s9api
Class XdmItem

java.lang.Object
  net.sf.saxon.s9api.XdmValue
      net.sf.saxon.s9api.XdmItem

All Implemented Interfaces:

Iterable<XdmItem>

Direct Known Subclasses:

XdmAtomicValue, XdmNode

public abstract class XdmItem
extends XdmValue

The class XdmItem represents an item in a sequence, as defined by the XDM data model. An item is either an atomic value or a node.

An item is a member of a sequence, but it can also be considered as a sequence (of length one) in its own right. XdmItem is a subtype of XdmValue because every Item in the XDM data model is also a value.

It cannot be assumed that every sequence of length one will be represented by an XdmItem. It is quite possible for an XdmValue that is not an XdmItem to hold a singleton sequence.

Saxon provides two concrete subclasses of XdmItem, namely XdmNode and XdmAtomicValue. Users must not attempt to create additional subclasses.

Method Summary

String	getStringValue() Get the string value of the item.
boolean	isAtomicValue() Determine whether the item is an atomic value or a node
static XdmItem	newAtomicValue(String value, ItemType type) Factory method to construct an atomic value given its lexical representation and the required item type
int	size() Get the number of items in the sequence

Methods inherited from class net.sf.saxon.s9api.XdmValue

getUnderlyingValue, itemAt, iterator

Methods inherited from class java.lang.Object

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

Method Detail

newAtomicValue

public static XdmItem newAtomicValue(String value,
                                     ItemType type)
                              throws SaxonApiException

Factory method to construct an atomic value given its lexical representation and the required item type

Parameters:

value - the lexical representation of the required value

type - the item type of the required value

Returns:

the constructed item

Throws:

SaxonApiException - if the supplied string is not in the lexical space of the target type, or if the target type is not atomic

getStringValue

public String getStringValue()

Get the string value of the item. For a node, this gets the string value of the node. For an atomic value, it has the same effect as casting the value to a string. In all cases the result is the same as applying the XPath string() function.

For atomic values, the result is the same as the result of calling toString. This is not the case for nodes, where toString returns an XML serialization of the node.

Returns:

the result of converting the item to a string.

isAtomicValue

public boolean isAtomicValue()

Determine whether the item is an atomic value or a node

Returns:

true if the item is an atomic value, false if it is a node

size

public int size()

Get the number of items in the sequence

Overrides:

size in class XdmValue

Returns:

the number of items in the value - always one