Skip to content

Most visited

Recently visited

navigation
Added in API level 8

QName

public class QName
extends Object implements Serializable

java.lang.Object
   ↳ javax.xml.namespace.QName


QName represents a qualified name as defined in the XML specifications: XML Schema Part2: Datatypes specification, Namespaces in XML, Namespaces in XML Errata.

The value of a QName contains a Namespace URI, local part and prefix.

The prefix is included in QName to retain lexical information when present in an XML input source. The prefix is NOT used in QName.equals(Object) or to compute the QName.hashCode(). Equality and the hash code are defined using only the Namespace URI and local part.

If not specified, the Namespace URI is set to XMLConstants.NULL_NS_URI. If not specified, the prefix is set to XMLConstants.DEFAULT_NS_PREFIX.

QName is immutable.

See also:

Summary

Public constructors

QName(String namespaceURI, String localPart)

QName constructor specifying the Namespace URI and local part.

QName(String namespaceURI, String localPart, String prefix)

QName constructor specifying the Namespace URI, local part and prefix.

QName(String localPart)

QName constructor specifying the local part.

Public methods

final boolean equals(Object objectToTest)

Test this QName for equality with another Object.

String getLocalPart()

Get the local part of this QName.

String getNamespaceURI()

Get the Namespace URI of this QName.

String getPrefix()

Get the prefix of this QName.

final int hashCode()

Generate the hash code for this QName.

String toString()

String representation of this QName.

static QName valueOf(String qNameAsString)

QName derived from parsing the formatted String.

Inherited methods

From class java.lang.Object

Public constructors

QName

Added in API level 8
QName (String namespaceURI, 
                String localPart)

QName constructor specifying the Namespace URI and local part.

If the Namespace URI is null, it is set to XMLConstants.NULL_NS_URI. This value represents no explicitly defined Namespace as defined by the Namespaces in XML specification. This action preserves compatible behavior with QName 1.0. Explicitly providing the XMLConstants.NULL_NS_URI value is the preferred coding style.

If the local part is null an IllegalArgumentException is thrown. A local part of "" is allowed to preserve compatible behavior with QName 1.0.

When using this constructor, the prefix is set to XMLConstants.DEFAULT_NS_PREFIX.

The Namespace URI is not validated as a URI reference. The local part is not validated as a NCName as specified in Namespaces in XML.

Parameters
namespaceURI String: Namespace URI of the QName
localPart String: local part of the QName

See also:

QName

Added in API level 8
QName (String namespaceURI, 
                String localPart, 
                String prefix)

QName constructor specifying the Namespace URI, local part and prefix.

If the Namespace URI is null, it is set to XMLConstants.NULL_NS_URI. This value represents no explicitly defined Namespace as defined by the Namespaces in XML specification. This action preserves compatible behavior with QName 1.0. Explicitly providing the XMLConstants.NULL_NS_URI value is the preferred coding style.

If the local part is null an IllegalArgumentException is thrown. A local part of "" is allowed to preserve compatible behavior with QName 1.0.

If the prefix is null, an IllegalArgumentException is thrown. Use XMLConstants.DEFAULT_NS_PREFIX to explicitly indicate that no prefix is present or the prefix is not relevant.

The Namespace URI is not validated as a URI reference. The local part and prefix are not validated as a NCName as specified in Namespaces in XML.

Parameters
namespaceURI String: Namespace URI of the QName
localPart String: local part of the QName
prefix String: prefix of the QName

QName

Added in API level 8
QName (String localPart)

QName constructor specifying the local part.

If the local part is null an IllegalArgumentException is thrown. A local part of "" is allowed to preserve compatible behavior with QName 1.0.

When using this constructor, the Namespace URI is set to XMLConstants.NULL_NS_URI and the prefix is set to XMLConstants.DEFAULT_NS_PREFIX.

In an XML context, all Element and Attribute names exist in the context of a Namespace. Making this explicit during the construction of a QName helps prevent hard to diagnosis XML validity errors. The constructors QName(String namespaceURI, String localPart) and QName(String, String, String) are preferred.

The local part is not validated as a NCName as specified in Namespaces in XML.

Parameters
localPart String: local part of the QName

See also:

Public methods

equals

Added in API level 8
boolean equals (Object objectToTest)

Test this QName for equality with another Object.

If the Object to be tested is not a QName or is null, then this method returns false.

Two QNames are considered equal if and only if both the Namespace URI and local part are equal. This method uses String.equals() to check equality of the Namespace URI and local part. The prefix is NOT used to determine equality.

This method satisfies the general contract of Object.equals(Object)

Parameters
objectToTest Object: the Object to test for equality with this QName
Returns
boolean true if the given Object is equal to this QName else false

getLocalPart

Added in API level 8
String getLocalPart ()

Get the local part of this QName.

Returns
String local part of this QName

getNamespaceURI

Added in API level 8
String getNamespaceURI ()

Get the Namespace URI of this QName.

Returns
String Namespace URI of this QName

getPrefix

Added in API level 8
String getPrefix ()

Get the prefix of this QName.

The prefix assigned to a QName might NOT be valid in a different context. For example, a QName may be assigned a prefix in the context of parsing a document but that prefix may be invalid in the context of a different document.

Returns
String prefix of this QName

hashCode

Added in API level 8
int hashCode ()

Generate the hash code for this QName.

The hash code is calculated using both the Namespace URI and the local part of the QName. The prefix is NOT used to calculate the hash code.

This method satisfies the general contract of Object.hashCode().

Returns
int hash code for this QName Object

toString

Added in API level 8
String toString ()

String representation of this QName.

The commonly accepted way of representing a QName as a String was defined by James Clark. Although this is not a standard specification, it is in common use, e.g. setParameter(String, Object). This implementation represents a QName as: "{" + Namespace URI + "}" + local part. If the Namespace URI .equals(XMLConstants.NULL_NS_URI), only the local part is returned. An appropriate use of this method is for debugging or logging for human consumption.

Note the prefix value is NOT returned as part of the String representation.

This method satisfies the general contract of Object.toString().

Returns
String String representation of this QName

valueOf

Added in API level 8
QName valueOf (String qNameAsString)

QName derived from parsing the formatted String.

If the String is null or does not conform to QName.toString() formatting, an IllegalArgumentException is thrown.

The String MUST be in the form returned by QName.toString().

The commonly accepted way of representing a QName as a String was defined by James Clark. Although this is not a standard specification, it is in common use, e.g. setParameter(String, Object). This implementation parses a String formatted as: "{" + Namespace URI + "}" + local part. If the Namespace URI .equals(XMLConstants.NULL_NS_URI), only the local part should be provided.

The prefix value CANNOT be represented in the String and will be set to XMLConstants.DEFAULT_NS_PREFIX.

This method does not do full validation of the resulting QName.

The Namespace URI is not validated as a URI reference. The local part is not validated as a NCName as specified in Namespaces in XML.

Parameters
qNameAsString String: String representation of the QName
Returns
QName QName corresponding to the given String

See also:

This site uses cookies to store your preferences for site-specific language and display options.

Hooray!

This class requires API level or higher

This doc is hidden because your selected API level for the documentation is . You can change the documentation API level with the selector above the left navigation.

For more information about specifying the API level your app requires, read Supporting Different Platform Versions.