NamespaceContext

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.

Public Method Summary

abstract String
getNamespaceURI(String prefix)

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

abstract String
getPrefix(String namespaceURI)

Get prefix bound to Namespace URI in the current scope.

abstract Iterator
getPrefixes(String namespaceURI)

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

Public Methods

public abstract 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

Parameters
prefix prefix to look up
Returns
  • Namespace URI bound to prefix in the current scope

public abstract 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).

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

Parameters
namespaceURI URI of Namespace to lookup
Returns
  • prefix bound to Namespace URI in current context

public abstract 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

Parameters
namespaceURI URI of Namespace to lookup
Returns
  • Iterator for all prefixes bound to the Namespace URI in the current scope