File	Doc	Category	Size	Date	Package
NamespaceSupport.java	API Doc	Android 1.5 API	26985	Wed May 06 22:41:06 BST 2009	org.xml.sax.helpers

NamespaceSupport

• java.lang.Object

String parts[] = new String[3];
NamespaceSupport support = new NamespaceSupport();

support.pushContext();
support.declarePrefix("", "http://www.w3.org/1999/xhtml");
support.declarePrefix("dc", "http://www.purl.org/dc#");

parts = support.processName("p", parts, false);
System.out.println("Namespace URI: " + parts[0]);
System.out.println("Local name: " + parts[1]);
System.out.println("Raw name: " + parts[2]);

parts = support.processName("dc:title", parts, false);
System.out.println("Namespace URI: " + parts[0]);
System.out.println("Local name: " + parts[1]);
System.out.println("Raw name: " + parts[2]);

support.popContext();

Fields Summary
public static final String	XMLNS The XML Namespace URI as a constant. The value is http://www.w3.org/XML/1998/namespace as defined in the "Namespaces in XML" * recommendation. This is the Namespace URI that is automatically mapped to the "xml" prefix.
public static final String	NSDECL The namespace declaration URI as a constant. The value is http://www.w3.org/xmlns/2000/, as defined in a backwards-incompatible erratum to the "Namespaces in XML" recommendation. Because that erratum postdated SAX2, SAX2 defaults to the original recommendation, and does not normally use this URI. This is the Namespace URI that is optionally applied to xmlns and xmlns:* attributes, which are used to declare namespaces.
private static final Enumeration	EMPTY_ENUMERATION An empty enumeration.
private Context[]	contexts
private Context	currentContext
private int	contextPos
private boolean	namespaceDeclUris

Constructors Summary
public NamespaceSupport() Create a new Namespace support object.  //////////////////////////////////////////////////////////////////// // Constructor. //////////////////////////////////////////////////////////////////// reset();

Methods Summary
public boolean	declarePrefix(java.lang.String prefix, java.lang.String uri) Declare a Namespace prefix. All prefixes must be declared before they are referenced. For example, a SAX driver (parser) would scan an element's attributes in two passes: first for namespace declarations, then a second pass using {@link #processName processName()} to interpret prefixes against (potentially redefined) prefixes. 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. To declare the default element Namespace, use the empty string as the prefix. Note that you must not declare a prefix after you've pushed and popped another Namespace context, or treated the declarations phase as complete by processing a prefixed name. Note that there is an asymmetry in this library: {@link #getPrefix getPrefix} will not return the "" prefix, even if you have declared a default element namespace. To check for a default namespace, you have to look it up explicitly using {@link #getURI getURI}. This asymmetry exists to make it easier to look up prefixes for attribute names, where the default prefix is not allowed. param prefix The prefix to declare, or the empty string to indicate the default element namespace. This may never have the value "xml" or "xmlns". param uri The Namespace URI to associate with the prefix. return true if the prefix was legal, false otherwise see #processName see #getURI see #getPrefix if (prefix.equals("xml") || prefix.equals("xmlns")) { return false; } else { currentContext.declarePrefix(prefix, uri); return true; }
public java.util.Enumeration	getDeclaredPrefixes() Return an enumeration of all prefixes declared in this context. The empty (default) prefix will be included in this enumeration; note that this behaviour differs from that of {@link #getPrefix} and {@link #getPrefixes}. return An enumeration of all prefixes declared in this context. see #getPrefixes see #getURI return currentContext.getDeclaredPrefixes();
public java.lang.String	getPrefix(java.lang.String uri) Return one of the prefixes mapped to a Namespace URI. If more than one prefix is currently mapped to the same URI, this method will make an arbitrary selection; if you want all of the prefixes, use the {@link #getPrefixes} method instead. Note: this will never return the empty (default) prefix; to check for a default prefix, use the {@link #getURI getURI} method with an argument of "". param uri the namespace URI return one of the prefixes currently mapped to the URI supplied, or null if none is mapped or if the URI is assigned to the default namespace see #getPrefixes(java.lang.String) see #getURI return currentContext.getPrefix(uri);
public java.util.Enumeration	getPrefixes(java.lang.String uri) Return an enumeration of all prefixes for a given URI whose declarations are active in the current context. This includes declarations from parent contexts that have not been overridden. This method returns prefixes mapped to a specific Namespace URI. The xml: prefix will be included. If you want only one prefix that's mapped to the Namespace URI, and you don't care which one you get, use the {@link #getPrefix getPrefix} method instead. Note: the empty (default) prefix is never included in this enumeration; to check for the presence of a default Namespace, use the {@link #getURI getURI} method with an argument of "". param uri The Namespace URI. return An enumeration of prefixes (never empty). see #getPrefix see #getDeclaredPrefixes see #getURI Vector prefixes = new Vector(); Enumeration allPrefixes = getPrefixes(); while (allPrefixes.hasMoreElements()) { String prefix = (String)allPrefixes.nextElement(); if (uri.equals(getURI(prefix))) { prefixes.addElement(prefix); } } return prefixes.elements();
public java.util.Enumeration	getPrefixes() 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. Note: if there is a default prefix, it will not be returned in this enumeration; check for the default prefix using the {@link #getURI getURI} with an argument of "". return An enumeration of prefixes (never empty). see #getDeclaredPrefixes see #getURI return currentContext.getPrefixes();
public java.lang.String	getURI(java.lang.String prefix) Look up a prefix and get the currently-mapped Namespace URI. This method looks up the prefix in the current context. 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. see #getPrefix see #getPrefixes return currentContext.getURI(prefix);
public boolean	isNamespaceDeclUris() Returns true if namespace declaration attributes are placed into a namespace. This behavior is not the default. return true if namespace declaration attributes are enabled, false otherwise. since SAX 2.1alpha return namespaceDeclUris;
public void	popContext() Revert to the previous Namespace context. Normally, you should pop the context at the end of each XML element. After popping the context, all Namespace prefix mappings that were previously in force are restored. You must not attempt to declare additional Namespace prefixes after popping a context, unless you push another context first. see #pushContext contexts[contextPos].clear(); contextPos--; if (contextPos < 0) { throw new EmptyStackException(); } currentContext = contexts[contextPos];
public java.lang.String[]	processName(java.lang.String qName, java.lang.String[] parts, boolean isAttribute) Process a raw XML qualified name, after all declarations in the current context have been handled by {@link #declarePrefix declarePrefix()}. This method processes a raw XML qualified name in the current context by removing the prefix and looking it up among the prefixes currently declared. The return value will be the array supplied by the caller, filled in as follows: parts[0] The Namespace URI, or an empty string if none is in use. parts[1] The local name (without prefix). parts[2] The original raw name. All of the strings in the array will be internalized. If the raw name has a prefix that has not been declared, then the return value will be null. Note that attribute names are processed differently than element names: an unprefixed element name will receive the default Namespace (if any), while an unprefixed attribute name will not. param qName The XML qualified name to be processed. param parts An array supplied by the caller, capable of holding at least three members. param isAttribute A flag indicating whether this is an attribute name (true) or an element name (false). return The supplied array holding three internalized strings representing the Namespace URI (or empty string), the local name, and the XML qualified name; or null if there is an undeclared prefix. see #declarePrefix see java.lang.String#intern String myParts[] = currentContext.processName(qName, isAttribute); if (myParts == null) { return null; } else { parts[0] = myParts[0]; parts[1] = myParts[1]; parts[2] = myParts[2]; return parts; }
public void	pushContext() Start a new Namespace context. 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. Event callback code should start a new context once per element. This means being ready to call this in either of two places. For elements that don't include namespace declarations, the ContentHandler.startElement() callback is the right place. For elements with such a declaration, it'd done in the first ContentHandler.startPrefixMapping() callback. A boolean flag can be used to track whether a context has been started yet. When either of those methods is called, it checks the flag to see if a new context needs to be started. If so, it starts the context and sets the flag. After ContentHandler.startElement() does that, it always clears the flag. Normally, SAX drivers would push a new context at the beginning of each XML element. Then they perform a first pass over the attributes to process all namespace declarations, making ContentHandler.startPrefixMapping() callbacks. Then a second pass is made, to determine the namespace-qualified names for all attributes and for the element name. Finally all the information for the ContentHandler.startElement() callback is available, so it can then be made. The Namespace support object always starts with a base context already in force: in this context, only the "xml" prefix is declared. see org.xml.sax.ContentHandler see #popContext int max = contexts.length; contexts [contextPos].declsOK = false; contextPos++; // Extend the array if necessary if (contextPos >= max) { Context newContexts[] = new Context[max*2]; System.arraycopy(contexts, 0, newContexts, 0, max); max *= 2; contexts = newContexts; } // Allocate the context if necessary. currentContext = contexts[contextPos]; if (currentContext == null) { contexts[contextPos] = currentContext = new Context(); } // Set the parent, if any. if (contextPos > 0) { currentContext.setParent(contexts[contextPos - 1]); }
public void	reset() Reset this Namespace support object for reuse. It is necessary to invoke this method before reusing the Namespace support object for a new session. If namespace declaration URIs are to be supported, that flag must also be set to a non-default value. see #setNamespaceDeclUris contexts = new Context[32]; namespaceDeclUris = false; contextPos = 0; contexts[contextPos] = currentContext = new Context(); currentContext.declarePrefix("xml", XMLNS);
public void	setNamespaceDeclUris(boolean value) Controls whether namespace declaration attributes are placed into the {@link #NSDECL NSDECL} namespace by {@link #processName processName()}. This may only be changed before any contexts have been pushed. param value the namespace declaration attribute state. A value of true enables this feature, a value of false disables it. since SAX 2.1alpha exception IllegalStateException when attempting to set this after any context has been pushed. if (contextPos != 0) throw new IllegalStateException (); if (value == namespaceDeclUris) return; namespaceDeclUris = value; if (value) currentContext.declarePrefix ("xmlns", NSDECL); else { contexts[contextPos] = currentContext = new Context(); currentContext.declarePrefix("xml", XMLNS); }