public interface NamespaceContext

Interface for read only XML Namespace context processing.

An XML Namespace has the properties:

• Namespace URI: Namespace name expressed as a URI to which the prefix is bound
• prefix: syntactically, this is the part of the attribute name following the XMLConstants.XMLNS_ATTRIBUTE ("xmlns") in the Namespace declaration

example: <element xmlns:prefix="http://Namespace-name-URI">

All get*(*) methods operate in the current scope for Namespace URI and prefix resolution.

Note that a Namespace URI can be bound to multiple prefixes in the current scope. This can occur when multiple XMLConstants.XMLNS_ATTRIBUTE ("xmlns") Namespace declarations occur in the same Start-Tag and refer to the same Namespace URI. e.g.

<element xmlns:prefix1="http://Namespace-name-URI"
          xmlns:prefix2="http://Namespace-name-URI">

This can also occur when the same Namespace URI is used in multiple XMLConstants.XMLNS_ATTRIBUTE ("xmlns") Namespace declarations in the logical parent element hierarchy. e.g.

<parent xmlns:prefix1="http://Namespace-name-URI">
   <child xmlns:prefix2="http://Namespace-name-URI">
     ...
   </child>
 </parent>

A prefix can only be bound to a single Namespace URI in the current scope.

String getNamespaceURI(String prefix)

Get Namespace URI bound to a prefix in the current scope.

When requesting a Namespace URI by prefix, the following table describes the returned Namespace URI value for all possible prefix values:

getNamespaceURI(prefix) return value for specified prefixes
prefix parameter	Namespace URI return value
DEFAULT_NS_PREFIX ("")	default Namespace URI in the current scope or XMLConstants.NULL_NS_URI("") when there is no default Namespace URI in the current scope
bound prefix	Namespace URI bound to prefix in current scope
unbound prefix	XMLConstants.NULL_NS_URI("")
XMLConstants.XML_NS_PREFIX ("xml")	XMLConstants.XML_NS_URI ("http://www.w3.org/XML/1998/namespace")
XMLConstants.XMLNS_ATTRIBUTE ("xmlns")	XMLConstants.XMLNS_ATTRIBUTE_NS_URI ("http://www.w3.org/2000/xmlns/")
null	IllegalArgumentException is thrown

String getPrefix(String namespaceURI)

Get prefix bound to Namespace URI in the current scope.

To get all prefixes bound to a Namespace URI in the current scope, use getPrefixes(String namespaceURI).

When requesting a prefix by Namespace URI, the following table describes the returned prefix value for all Namespace URI values:

getPrefix(namespaceURI) return value for specified Namespace URIs
Namespace URI parameter	prefix value returned
<default Namespace URI>	XMLConstants.DEFAULT_NS_PREFIX ("")
bound Namespace URI	prefix bound to Namespace URI in the current scope, if multiple prefixes are bound to the Namespace URI in the current scope, a single arbitrary prefix, whose choice is implementation dependent, is returned
unbound Namespace URI	null
XMLConstants.XML_NS_URI ("http://www.w3.org/XML/1998/namespace")	XMLConstants.XML_NS_PREFIX ("xml")
XMLConstants.XMLNS_ATTRIBUTE_NS_URI ("http://www.w3.org/2000/xmlns/")	XMLConstants.XMLNS_ATTRIBUTE ("xmlns")
null	IllegalArgumentException is thrown

Iterator getPrefixes(String namespaceURI)

Get all prefixes bound to a Namespace URI in the current scope.

An Iterator over String elements is returned in an arbitrary, implementation dependent, order.

The Iterator is not modifiable. e.g. the remove() method will throw UnsupportedOperationException.

When requesting prefixes by Namespace URI, the following table describes the returned prefixes value for all Namespace URI values:

getPrefixes(namespaceURI) return value for specified Namespace URIs
Namespace URI parameter	prefixes value returned
bound Namespace URI, including the <default Namespace URI>	Iterator over prefixes bound to Namespace URI in the current scope in an arbitrary, implementation dependent, order
unbound Namespace URI	empty Iterator
XMLConstants.XML_NS_URI ("http://www.w3.org/XML/1998/namespace")	Iterator with one element set to XMLConstants.XML_NS_PREFIX ("xml")
XMLConstants.XMLNS_ATTRIBUTE_NS_URI ("http://www.w3.org/2000/xmlns/")	Iterator with one element set to XMLConstants.XMLNS_ATTRIBUTE ("xmlns")
null	IllegalArgumentException is thrown