mirror of git://gcc.gnu.org/git/gcc.git
399 lines
14 KiB
Java
399 lines
14 KiB
Java
// XMLReader.java - read an XML document.
|
||
// http://www.saxproject.org
|
||
// Written by David Megginson
|
||
// NO WARRANTY! This class is in the Public Domain.
|
||
|
||
// $Id: XMLReader.java,v 1.3.2.5 2002/01/29 21:34:14 dbrownell Exp $
|
||
|
||
package org.xml.sax;
|
||
|
||
import java.io.IOException;
|
||
|
||
|
||
/**
|
||
* Interface for reading an XML document using callbacks.
|
||
*
|
||
* <blockquote>
|
||
* <em>This module, both source code and documentation, is in the
|
||
* Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
|
||
* See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
|
||
* for further information.
|
||
* </blockquote>
|
||
*
|
||
* <p><strong>Note:</strong> despite its name, this interface does
|
||
* <em>not</em> extend the standard Java {@link java.io.Reader Reader}
|
||
* interface, because reading XML is a fundamentally different activity
|
||
* than reading character data.</p>
|
||
*
|
||
* <p>XMLReader is the interface that an XML parser's SAX2 driver must
|
||
* implement. This interface allows an application to set and
|
||
* query features and properties in the parser, to register
|
||
* event handlers for document processing, and to initiate
|
||
* a document parse.</p>
|
||
*
|
||
* <p>All SAX interfaces are assumed to be synchronous: the
|
||
* {@link #parse parse} methods must not return until parsing
|
||
* is complete, and readers must wait for an event-handler callback
|
||
* to return before reporting the next event.</p>
|
||
*
|
||
* <p>This interface replaces the (now deprecated) SAX 1.0 {@link
|
||
* org.xml.sax.Parser Parser} interface. The XMLReader interface
|
||
* contains two important enhancements over the old Parser
|
||
* interface (as well as some minor ones):</p>
|
||
*
|
||
* <ol>
|
||
* <li>it adds a standard way to query and set features and
|
||
* properties; and</li>
|
||
* <li>it adds Namespace support, which is required for many
|
||
* higher-level XML standards.</li>
|
||
* </ol>
|
||
*
|
||
* <p>There are adapters available to convert a SAX1 Parser to
|
||
* a SAX2 XMLReader and vice-versa.</p>
|
||
*
|
||
* @since SAX 2.0
|
||
* @author David Megginson
|
||
* @version 2.0.1 (sax2r2)
|
||
* @see org.xml.sax.XMLFilter
|
||
* @see org.xml.sax.helpers.ParserAdapter
|
||
* @see org.xml.sax.helpers.XMLReaderAdapter
|
||
*/
|
||
public interface XMLReader
|
||
{
|
||
|
||
|
||
////////////////////////////////////////////////////////////////////
|
||
// Configuration.
|
||
////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
/**
|
||
* Look up the value of a feature flag.
|
||
*
|
||
* <p>The feature name is any fully-qualified URI. It is
|
||
* possible for an XMLReader to recognize a feature name but
|
||
* temporarily be unable to return its value.
|
||
* Some feature values may be available only in specific
|
||
* contexts, such as before, during, or after a parse.
|
||
* Also, some feature values may not be programmatically accessible.
|
||
* (In the case of an adapter for SAX1 {@link Parser}, there is no
|
||
* implementation-independent way to expose whether the underlying
|
||
* parser is performing validation, expanding external entities,
|
||
* and so forth.) </p>
|
||
*
|
||
* <p>All XMLReaders are required to recognize the
|
||
* http://xml.org/sax/features/namespaces and the
|
||
* http://xml.org/sax/features/namespace-prefixes feature names.</p>
|
||
*
|
||
* <p>Typical usage is something like this:</p>
|
||
*
|
||
* <pre>
|
||
* XMLReader r = new MySAXDriver();
|
||
*
|
||
* // try to activate validation
|
||
* try {
|
||
* r.setFeature("http://xml.org/sax/features/validation", true);
|
||
* } catch (SAXException e) {
|
||
* System.err.println("Cannot activate validation.");
|
||
* }
|
||
*
|
||
* // register event handlers
|
||
* r.setContentHandler(new MyContentHandler());
|
||
* r.setErrorHandler(new MyErrorHandler());
|
||
*
|
||
* // parse the first document
|
||
* try {
|
||
* r.parse("http://www.foo.com/mydoc.xml");
|
||
* } catch (IOException e) {
|
||
* System.err.println("I/O exception reading XML document");
|
||
* } catch (SAXException e) {
|
||
* System.err.println("XML exception reading document.");
|
||
* }
|
||
* </pre>
|
||
*
|
||
* <p>Implementors are free (and encouraged) to invent their own features,
|
||
* using names built on their own URIs.</p>
|
||
*
|
||
* @param name The feature name, which is a fully-qualified URI.
|
||
* @return The current value of the feature (true or false).
|
||
* @exception org.xml.sax.SAXNotRecognizedException If the feature
|
||
* value can't be assigned or retrieved.
|
||
* @exception org.xml.sax.SAXNotSupportedException When the
|
||
* XMLReader recognizes the feature name but
|
||
* cannot determine its value at this time.
|
||
* @see #setFeature
|
||
*/
|
||
public boolean getFeature (String name)
|
||
throws SAXNotRecognizedException, SAXNotSupportedException;
|
||
|
||
|
||
/**
|
||
* Set the value of a feature flag.
|
||
*
|
||
* <p>The feature name is any fully-qualified URI. It is
|
||
* possible for an XMLReader to expose a feature value but
|
||
* to be unable to change the current value.
|
||
* Some feature values may be immutable or mutable only
|
||
* in specific contexts, such as before, during, or after
|
||
* a parse.</p>
|
||
*
|
||
* <p>All XMLReaders are required to support setting
|
||
* http://xml.org/sax/features/namespaces to true and
|
||
* http://xml.org/sax/features/namespace-prefixes to false.</p>
|
||
*
|
||
* @param name The feature name, which is a fully-qualified URI.
|
||
* @param value The requested value of the feature (true or false).
|
||
* @exception org.xml.sax.SAXNotRecognizedException If the feature
|
||
* value can't be assigned or retrieved.
|
||
* @exception org.xml.sax.SAXNotSupportedException When the
|
||
* XMLReader recognizes the feature name but
|
||
* cannot set the requested value.
|
||
* @see #getFeature
|
||
*/
|
||
public void setFeature (String name, boolean value)
|
||
throws SAXNotRecognizedException, SAXNotSupportedException;
|
||
|
||
|
||
/**
|
||
* Look up the value of a property.
|
||
*
|
||
* <p>The property name is any fully-qualified URI. It is
|
||
* possible for an XMLReader to recognize a property name but
|
||
* temporarily be unable to return its value.
|
||
* Some property values may be available only in specific
|
||
* contexts, such as before, during, or after a parse.</p>
|
||
*
|
||
* <p>XMLReaders are not required to recognize any specific
|
||
* property names, though an initial core set is documented for
|
||
* SAX2.</p>
|
||
*
|
||
* <p>Implementors are free (and encouraged) to invent their own properties,
|
||
* using names built on their own URIs.</p>
|
||
*
|
||
* @param name The property name, which is a fully-qualified URI.
|
||
* @return The current value of the property.
|
||
* @exception org.xml.sax.SAXNotRecognizedException If the property
|
||
* value can't be assigned or retrieved.
|
||
* @exception org.xml.sax.SAXNotSupportedException When the
|
||
* XMLReader recognizes the property name but
|
||
* cannot determine its value at this time.
|
||
* @see #setProperty
|
||
*/
|
||
public Object getProperty (String name)
|
||
throws SAXNotRecognizedException, SAXNotSupportedException;
|
||
|
||
|
||
/**
|
||
* Set the value of a property.
|
||
*
|
||
* <p>The property name is any fully-qualified URI. It is
|
||
* possible for an XMLReader to recognize a property name but
|
||
* to be unable to change the current value.
|
||
* Some property values may be immutable or mutable only
|
||
* in specific contexts, such as before, during, or after
|
||
* a parse.</p>
|
||
*
|
||
* <p>XMLReaders are not required to recognize setting
|
||
* any specific property names, though a core set is defined by
|
||
* SAX2.</p>
|
||
*
|
||
* <p>This method is also the standard mechanism for setting
|
||
* extended handlers.</p>
|
||
*
|
||
* @param name The property name, which is a fully-qualified URI.
|
||
* @param value The requested value for the property.
|
||
* @exception org.xml.sax.SAXNotRecognizedException If the property
|
||
* value can't be assigned or retrieved.
|
||
* @exception org.xml.sax.SAXNotSupportedException When the
|
||
* XMLReader recognizes the property name but
|
||
* cannot set the requested value.
|
||
*/
|
||
public void setProperty (String name, Object value)
|
||
throws SAXNotRecognizedException, SAXNotSupportedException;
|
||
|
||
|
||
|
||
////////////////////////////////////////////////////////////////////
|
||
// Event handlers.
|
||
////////////////////////////////////////////////////////////////////
|
||
|
||
|
||
/**
|
||
* Allow an application to register an entity resolver.
|
||
*
|
||
* <p>If the application does not register an entity resolver,
|
||
* the XMLReader will perform its own default resolution.</p>
|
||
*
|
||
* <p>Applications may register a new or different resolver in the
|
||
* middle of a parse, and the SAX parser must begin using the new
|
||
* resolver immediately.</p>
|
||
*
|
||
* @param resolver The entity resolver.
|
||
* @see #getEntityResolver
|
||
*/
|
||
public void setEntityResolver (EntityResolver resolver);
|
||
|
||
|
||
/**
|
||
* Return the current entity resolver.
|
||
*
|
||
* @return The current entity resolver, or null if none
|
||
* has been registered.
|
||
* @see #setEntityResolver
|
||
*/
|
||
public EntityResolver getEntityResolver ();
|
||
|
||
|
||
/**
|
||
* Allow an application to register a DTD event handler.
|
||
*
|
||
* <p>If the application does not register a DTD handler, all DTD
|
||
* events reported by the SAX parser will be silently ignored.</p>
|
||
*
|
||
* <p>Applications may register a new or different handler in the
|
||
* middle of a parse, and the SAX parser must begin using the new
|
||
* handler immediately.</p>
|
||
*
|
||
* @param handler The DTD handler.
|
||
* @see #getDTDHandler
|
||
*/
|
||
public void setDTDHandler (DTDHandler handler);
|
||
|
||
|
||
/**
|
||
* Return the current DTD handler.
|
||
*
|
||
* @return The current DTD handler, or null if none
|
||
* has been registered.
|
||
* @see #setDTDHandler
|
||
*/
|
||
public DTDHandler getDTDHandler ();
|
||
|
||
|
||
/**
|
||
* Allow an application to register a content event handler.
|
||
*
|
||
* <p>If the application does not register a content handler, all
|
||
* content events reported by the SAX parser will be silently
|
||
* ignored.</p>
|
||
*
|
||
* <p>Applications may register a new or different handler in the
|
||
* middle of a parse, and the SAX parser must begin using the new
|
||
* handler immediately.</p>
|
||
*
|
||
* @param handler The content handler.
|
||
* @see #getContentHandler
|
||
*/
|
||
public void setContentHandler (ContentHandler handler);
|
||
|
||
|
||
/**
|
||
* Return the current content handler.
|
||
*
|
||
* @return The current content handler, or null if none
|
||
* has been registered.
|
||
* @see #setContentHandler
|
||
*/
|
||
public ContentHandler getContentHandler ();
|
||
|
||
|
||
/**
|
||
* Allow an application to register an error event handler.
|
||
*
|
||
* <p>If the application does not register an error handler, all
|
||
* error events reported by the SAX parser will be silently
|
||
* ignored; however, normal processing may not continue. It is
|
||
* highly recommended that all SAX applications implement an
|
||
* error handler to avoid unexpected bugs.</p>
|
||
*
|
||
* <p>Applications may register a new or different handler in the
|
||
* middle of a parse, and the SAX parser must begin using the new
|
||
* handler immediately.</p>
|
||
*
|
||
* @param handler The error handler.
|
||
* @see #getErrorHandler
|
||
*/
|
||
public void setErrorHandler (ErrorHandler handler);
|
||
|
||
|
||
/**
|
||
* Return the current error handler.
|
||
*
|
||
* @return The current error handler, or null if none
|
||
* has been registered.
|
||
* @see #setErrorHandler
|
||
*/
|
||
public ErrorHandler getErrorHandler ();
|
||
|
||
|
||
|
||
////////////////////////////////////////////////////////////////////
|
||
// Parsing.
|
||
////////////////////////////////////////////////////////////////////
|
||
|
||
/**
|
||
* Parse an XML document.
|
||
*
|
||
* <p>The application can use this method to instruct the XML
|
||
* reader to begin parsing an XML document from any valid input
|
||
* source (a character stream, a byte stream, or a URI).</p>
|
||
*
|
||
* <p>Applications may not invoke this method while a parse is in
|
||
* progress (they should create a new XMLReader instead for each
|
||
* nested XML document). Once a parse is complete, an
|
||
* application may reuse the same XMLReader object, possibly with a
|
||
* different input source.</p>
|
||
*
|
||
* <p>During the parse, the XMLReader will provide information
|
||
* about the XML document through the registered event
|
||
* handlers.</p>
|
||
*
|
||
* <p>This method is synchronous: it will not return until parsing
|
||
* has ended. If a client application wants to terminate
|
||
* parsing early, it should throw an exception.</p>
|
||
*
|
||
* @param source The input source for the top-level of the
|
||
* XML document.
|
||
* @exception org.xml.sax.SAXException Any SAX exception, possibly
|
||
* wrapping another exception.
|
||
* @exception java.io.IOException An IO exception from the parser,
|
||
* possibly from a byte stream or character stream
|
||
* supplied by the application.
|
||
* @see org.xml.sax.InputSource
|
||
* @see #parse(java.lang.String)
|
||
* @see #setEntityResolver
|
||
* @see #setDTDHandler
|
||
* @see #setContentHandler
|
||
* @see #setErrorHandler
|
||
*/
|
||
public void parse (InputSource input)
|
||
throws IOException, SAXException;
|
||
|
||
|
||
/**
|
||
* Parse an XML document from a system identifier (URI).
|
||
*
|
||
* <p>This method is a shortcut for the common case of reading a
|
||
* document from a system identifier. It is the exact
|
||
* equivalent of the following:</p>
|
||
*
|
||
* <pre>
|
||
* parse(new InputSource(systemId));
|
||
* </pre>
|
||
*
|
||
* <p>If the system identifier is a URL, it must be fully resolved
|
||
* by the application before it is passed to the parser.</p>
|
||
*
|
||
* @param systemId The system identifier (URI).
|
||
* @exception org.xml.sax.SAXException Any SAX exception, possibly
|
||
* wrapping another exception.
|
||
* @exception java.io.IOException An IO exception from the parser,
|
||
* possibly from a byte stream or character stream
|
||
* supplied by the application.
|
||
* @see #parse(org.xml.sax.InputSource)
|
||
*/
|
||
public void parse (String systemId)
|
||
throws IOException, SAXException;
|
||
|
||
}
|