org.apache.xerces.util
Class NamespaceSupport

java.lang.Object
  extended by org.apache.xerces.util.NamespaceSupport
All Implemented Interfaces:
org.apache.xerces.xni.NamespaceContext
Direct Known Subclasses:
MultipleScopeNamespaceSupport, SchemaNamespaceSupport

public class NamespaceSupport
extends java.lang.Object
implements org.apache.xerces.xni.NamespaceContext

Namespace support for XML document handlers. This class doesn't perform any error checking and assumes that all strings passed as arguments to methods are unique symbols. The SymbolTable class can be used for this purpose.

Version:
$Id: NamespaceSupport.java 965250 2010-07-18 16:04:58Z mrglavas $
Author:
Andy Clark, IBM

Nested Class Summary
protected  class NamespaceSupport.Prefixes
           
 
Field Summary
protected  int[] fContext
          Context indexes.
protected  int fCurrentContext
          The current context.
protected  java.lang.String[] fNamespace
          Namespace binding information.
protected  int fNamespaceSize
          The top of the namespace information array.
protected  java.lang.String[] fPrefixes
           
 
Fields inherited from interface org.apache.xerces.xni.NamespaceContext
XML_URI, XMLNS_URI
 
Constructor Summary
NamespaceSupport()
          Default constructor.
NamespaceSupport(org.apache.xerces.xni.NamespaceContext context)
          Constructs a namespace context object and initializes it with the prefixes declared in the specified context.
 
Method Summary
 boolean containsPrefix(java.lang.String prefix)
          Checks whether a binding or unbinding for the given prefix exists in the context.
 boolean declarePrefix(java.lang.String prefix, java.lang.String uri)
          Declare a Namespace prefix.
 java.util.Enumeration getAllPrefixes()
          Return an enumeration of all prefixes whose declarations are active in the current context.
 java.lang.String getDeclaredPrefixAt(int index)
          Returns the prefix at the specified index in the current context.
 int getDeclaredPrefixCount()
          Return a count of locally declared prefixes, including the default prefix if bound.
 java.lang.String getPrefix(java.lang.String uri)
          Look up a namespace URI and get one of the mapped prefix.
 java.lang.String getURI(java.lang.String prefix)
          Look up a prefix and get the currently-mapped Namespace URI.
 void popContext()
          Revert to the previous Namespace context.
 void pushContext()
          Start a new Namespace context.
 void reset()
          Reset this Namespace support object for reuse.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

fNamespace

protected java.lang.String[] fNamespace
Namespace binding information. This array is composed of a series of tuples containing the namespace binding information: <prefix, uri>. The default size can be set to anything as long as it is a power of 2 greater than 1.

See Also:
fNamespaceSize, fContext

fNamespaceSize

protected int fNamespaceSize
The top of the namespace information array.


fContext

protected int[] fContext
Context indexes. This array contains indexes into the namespace information array. The index at the current context is the start index of declared namespace bindings and runs to the size of the namespace information array.

See Also:
fNamespaceSize

fCurrentContext

protected int fCurrentContext
The current context.


fPrefixes

protected java.lang.String[] fPrefixes
Constructor Detail

NamespaceSupport

public NamespaceSupport()
Default constructor.


NamespaceSupport

public NamespaceSupport(org.apache.xerces.xni.NamespaceContext context)
Constructs a namespace context object and initializes it with the prefixes declared in the specified context.

Method Detail

reset

public void reset()
Description copied from interface: org.apache.xerces.xni.NamespaceContext
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.

Specified by:
reset in interface org.apache.xerces.xni.NamespaceContext
See Also:
NamespaceContext.reset()

pushContext

public void pushContext()
Description copied from interface: org.apache.xerces.xni.NamespaceContext
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.

Specified by:
pushContext in interface org.apache.xerces.xni.NamespaceContext
See Also:
NamespaceContext.pushContext()

popContext

public void popContext()
Description copied from interface: org.apache.xerces.xni.NamespaceContext
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.

Specified by:
popContext in interface org.apache.xerces.xni.NamespaceContext
See Also:
NamespaceContext.popContext()

declarePrefix

public boolean declarePrefix(java.lang.String prefix,
                             java.lang.String uri)
Description copied from interface: org.apache.xerces.xni.NamespaceContext
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.

Specified by:
declarePrefix in interface org.apache.xerces.xni.NamespaceContext
Parameters:
prefix - The prefix to declare, or null for the empty string.
uri - The Namespace URI to associate with the prefix.
Returns:
true if the prefix was legal, false otherwise
See Also:
NamespaceContext.declarePrefix(String, String)

getURI

public java.lang.String getURI(java.lang.String prefix)
Description copied from interface: org.apache.xerces.xni.NamespaceContext
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.

Specified by:
getURI in interface org.apache.xerces.xni.NamespaceContext
Parameters:
prefix - The prefix to look up.
Returns:
The associated Namespace URI, or null if the prefix is undeclared in this context.
See Also:
NamespaceContext.getURI(String)

getPrefix

public java.lang.String getPrefix(java.lang.String uri)
Description copied from interface: org.apache.xerces.xni.NamespaceContext
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).

Specified by:
getPrefix in interface org.apache.xerces.xni.NamespaceContext
Parameters:
uri - The namespace URI to look up.
Returns:
One of the associated prefixes, or null if the uri does not map to any prefix.
See Also:
NamespaceContext.getPrefix(String)

getDeclaredPrefixCount

public int getDeclaredPrefixCount()
Description copied from interface: org.apache.xerces.xni.NamespaceContext
Return a count of locally declared prefixes, including the default prefix if bound.

Specified by:
getDeclaredPrefixCount in interface org.apache.xerces.xni.NamespaceContext
See Also:
NamespaceContext.getDeclaredPrefixCount()

getDeclaredPrefixAt

public java.lang.String getDeclaredPrefixAt(int index)
Description copied from interface: org.apache.xerces.xni.NamespaceContext
Returns the prefix at the specified index in the current context.

Specified by:
getDeclaredPrefixAt in interface org.apache.xerces.xni.NamespaceContext
See Also:
NamespaceContext.getDeclaredPrefixAt(int)

getAllPrefixes

public java.util.Enumeration getAllPrefixes()
Description copied from interface: org.apache.xerces.xni.NamespaceContext
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.

Specified by:
getAllPrefixes in interface org.apache.xerces.xni.NamespaceContext
Returns:
Enumeration
See Also:
NamespaceContext.getAllPrefixes()

containsPrefix

public boolean containsPrefix(java.lang.String prefix)
Checks whether a binding or unbinding for the given prefix exists in the context.

Parameters:
prefix - The prefix to look up.
Returns:
true if the given prefix exists in the context


Copyright 1999-2010 The Apache Software Foundation. All Rights Reserved.