org.apache.xpath.domapi
Class XPathResultImpl

java.lang.Object
  org.apache.xpath.domapi.XPathResultImpl

All Implemented Interfaces:

EventListener, XPathResult

public class XPathResultImpl

extends java.lang.Object

implements XPathResult, EventListener

The class provides an implementation XPathResult according to the DOM L3 XPath Specification, Working Draft 28, March 2002.

See also the Document Object Model (DOM) Level 3 XPath Specification.

The XPathResult interface represents the result of the evaluation of an XPath expression within the context of a particular node. Since evaluation of an XPath expression can result in various result types, this object makes it possible to discover and manipulate the type and value of the result.

This implementation wraps an XObject.

See Also:

XObject, XPathResult

Field Summary

Fields inherited from interface org.w3c.dom.xpath.XPathResult

ANY_TYPE, ANY_UNORDERED_NODE_TYPE, BOOLEAN_TYPE, FIRST_ORDERED_NODE_TYPE, NUMBER_TYPE, ORDERED_NODE_ITERATOR_TYPE, ORDERED_NODE_SNAPSHOT_TYPE, STRING_TYPE, UNORDERED_NODE_ITERATOR_TYPE, UNORDERED_NODE_SNAPSHOT_TYPE

Method Summary

boolean	getBooleanValue() The value of this boolean result.
boolean	getInvalidIteratorState() Signifies that the iterator has become invalid.
double	getNumberValue() The value of this number result.
short	getResultType() A code representing the type of this result, as defined by the type constants.
Node	getSingleNodeValue() The value of this single node result, which may be null.
int	getSnapshotLength() The number of nodes in the result snapshot.
java.lang.String	getStringValue() The value of this string result.
java.lang.String	getTypeString(int type) Given a request type, return the equivalent string.
void	handleEvent(Event event) This method is called whenever an event occurs of the type for which the EventListener interface was registered.
static boolean	isValidType(short type) Check if the specified type is one of the supported types.
Node	iterateNext() Iterates and returns the next node from the node set or nullif there are no more nodes.
Node	snapshotItem(int index) Returns the indexth item in the snapshot collection.

Methods inherited from class java.lang.Object

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

Method Detail

getResultType

public short getResultType()

Description copied from interface: XPathResult

A code representing the type of this result, as defined by the type constants.

Specified by:

getResultType in interface XPathResult

See Also:

XPathResult.getResultType()

getNumberValue

public double getNumberValue()
                      throws XPathException

The value of this number result.

Specified by:

getNumberValue in interface XPathResult

Throws:

XPathException - TYPE_ERR: raised if resultType is not NUMBER_TYPE.

See Also:

XPathResult.getNumberValue()

getStringValue

public java.lang.String getStringValue()
                                throws XPathException

The value of this string result.

Specified by:

getStringValue in interface XPathResult

Throws:

XPathException - TYPE_ERR: raised if resultType is not STRING_TYPE.

See Also:

XPathResult.getStringValue()

getBooleanValue

public boolean getBooleanValue()
                        throws XPathException

Description copied from interface: XPathResult

The value of this boolean result.

Specified by:

getBooleanValue in interface XPathResult

Throws:

XPathException - TYPE_ERR: raised if resultType is not BOOLEAN_TYPE.

See Also:

XPathResult.getBooleanValue()

getSingleNodeValue

public Node getSingleNodeValue()
                        throws XPathException

The value of this single node result, which may be null.

Specified by:

getSingleNodeValue in interface XPathResult

Throws:

XPathException - TYPE_ERR: raised if resultType is not ANY_UNORDERED_NODE_TYPE or FIRST_ORDERED_NODE_TYPE.

See Also:

XPathResult.getSingleNodeValue()

getInvalidIteratorState

public boolean getInvalidIteratorState()

Description copied from interface: XPathResult

Signifies that the iterator has become invalid. True if resultType is UNORDERED_NODE_ITERATOR_TYPE or ORDERED_NODE_ITERATOR_TYPE and the document has been modified since this result was returned.

Specified by:

getInvalidIteratorState in interface XPathResult

See Also:

XPathResult.getInvalidIteratorState()

getSnapshotLength

public int getSnapshotLength()
                      throws XPathException

The number of nodes in the result snapshot. Valid values for snapshotItem indices are 0 to snapshotLength-1 inclusive.

Specified by:

getSnapshotLength in interface XPathResult

Throws:

XPathException - TYPE_ERR: raised if resultType is not UNORDERED_NODE_SNAPSHOT_TYPE or ORDERED_NODE_SNAPSHOT_TYPE.

See Also:

XPathResult.getSnapshotLength()

iterateNext

public Node iterateNext()
                 throws XPathException,
                        DOMException

Iterates and returns the next node from the node set or nullif there are no more nodes.

Specified by:

iterateNext in interface XPathResult

Returns:

Returns the next node.

Throws:

XPathException - TYPE_ERR: raised if resultType is not UNORDERED_NODE_ITERATOR_TYPE or ORDERED_NODE_ITERATOR_TYPE.

DOMException - INVALID_STATE_ERR: The document has been mutated since the result was returned.

See Also:

XPathResult.iterateNext()

snapshotItem

public Node snapshotItem(int index)
                  throws XPathException

Returns the indexth item in the snapshot collection. If index is greater than or equal to the number of nodes in the list, this method returns null. Unlike the iterator result, the snapshot does not become invalid, but may not correspond to the current document if it is mutated.

Specified by:

snapshotItem in interface XPathResult

Parameters:

index - Index into the snapshot collection.

Returns:

The node at the indexth position in the NodeList, or null if that is not a valid index.

Throws:

XPathException - TYPE_ERR: raised if resultType is not UNORDERED_NODE_SNAPSHOT_TYPE or ORDERED_NODE_SNAPSHOT_TYPE.

See Also:

XPathResult.snapshotItem(int)

isValidType

public static boolean isValidType(short type)

Check if the specified type is one of the supported types.

Parameters:

type - The specified type

Returns:

true If the specified type is supported; otherwise, returns false.

handleEvent

public void handleEvent(Event event)

Description copied from interface: EventListener

This method is called whenever an event occurs of the type for which the EventListener interface was registered.

Specified by:

handleEvent in interface EventListener

Parameters:

event - The Event contains contextual information about the event. It also contains the stopPropagation and preventDefault methods which are used in determining the event's flow and default action.

See Also:

EventListener.handleEvent(Event)

getTypeString

public java.lang.String getTypeString(int type)

Given a request type, return the equivalent string. For diagnostic purposes.

Returns:

type string