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Interface 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.

Since:

1.5

See Also:

Method Summary

Modifier and Type	Method	Description
`String`	`getNamespaceURI(String prefix)`	Get Namespace URI bound to a prefix in the current scope.
`String`	`getPrefix(String namespaceURI)`	Get prefix bound to Namespace URI in the current scope.
`Iterator<String>`	`getPrefixes(String namespaceURI)`	Get all prefixes bound to a Namespace URI in the current scope.

Method Details

getNamespaceURI

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:

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
Throws:: IllegalArgumentException - When prefix is null

getPrefix

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:

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
Throws:: IllegalArgumentException - When namespaceURI is null

getPrefixes

Iterator<String> 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:

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
Throws:: IllegalArgumentException - When namespaceURI is null

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