* The prefix and namespace must be identical references for equal strings, thus
* each string should be internalized (@see String.intern())
* or added to the SymbolTable
*
* @see
* org.apache.xerces.util.SymbolTable
*
* @author Andy Clark, IBM
*
* @version $Id: NamespaceContext.java,v 1.10 2003/01/23 17:27:12 sandygao Exp $
*/
public interface NamespaceContext {
//
// Constants
//
/**
* The XML Namespace ("http://www.w3.org/XML/1998/namespace"). This is
* the Namespace URI that is automatically mapped to the "xml" prefix.
*/
public final static String XML_URI = "http://www.w3.org/XML/1998/namespace".intern();
/**
* XML Information Set REC
* all namespace attributes (including those named xmlns,
* whose [prefix] property has no value) have a namespace URI of http://www.w3.org/2000/xmlns/
*/
public final static String XMLNS_URI = "http://www.w3.org/2000/xmlns/".intern();
//
// NamespaceContext methods
//
/**
* Start a new Namespace context.
*
* A new context should be pushed at the beginning * of each XML element: the new context will automatically inherit * the declarations of its parent context, but it will also keep * track of which declarations were made within this context. *
* * @see #popContext */ public void pushContext(); /** * Revert to the previous Namespace context. *
* The context should be popped at the end of each * XML element. After popping the context, all Namespace prefix * mappings that were previously in force are restored. *
* Users must not attempt to declare additional Namespace * prefixes after popping a context, unless you push another * context first. * * @see #pushContext */ public void popContext(); /** * Declare a Namespace prefix. *
* This method declares a prefix in the current Namespace * context; the prefix will remain in force until this context * is popped, unless it is shadowed in a descendant context. *
* Note that to declare a default Namespace, use the empty string. * The prefixes "xml" and "xmlns" can't be rebound. *
* Note that you must not declare a prefix after * you've pushed and popped another Namespace. * * @param prefix The prefix to declare, or null for the empty * string. * @param uri The Namespace URI to associate with the prefix. * * @return true if the prefix was legal, false otherwise * * @see #getURI * @see #getDeclaredPrefixAt */ public boolean declarePrefix(String prefix, String uri); /** * Look up a prefix and get the currently-mapped Namespace URI. *
* This method looks up the prefix in the current context. If no mapping * is found, this methods will continue lookup in the parent context(s). * Use the empty string ("") for the default Namespace. * * @param prefix The prefix to look up. * * @return The associated Namespace URI, or null if the prefix * is undeclared in this context. */ public String getURI(String prefix); /** * Look up a namespace URI and get one of the mapped prefix. *
* This method looks up the namespace URI in the current context. * If more than one prefix is currently mapped to the same URI, * this method will make an arbitrary selection * If no mapping is found, this methods will continue lookup in the * parent context(s). * * @param uri The namespace URI to look up. * * @return One of the associated prefixes, or null if the uri * does not map to any prefix. * * @see #getPrefix */ public String getPrefix(String uri); /** * Return a count of locally declared prefixes, including * the default prefix if bound. */ public int getDeclaredPrefixCount(); /** * Returns the prefix at the specified index in the current context. */ public String getDeclaredPrefixAt(int index); /** * Return an enumeration of all prefixes whose declarations are active * in the current context. This includes declarations from parent contexts * that have not been overridden. * @return Enumeration */ public Enumeration getAllPrefixes(); /** * Reset this Namespace support object for reuse. * *
It is necessary to invoke this method before reusing the * Namespace support object for a new session.
* *Note that implementations of this method need to ensure that * the declaration of the prefixes "xmlns" and "xml" are available.
*/ public void reset(); } // interface NamespaceContext