http://xml.apache.org/commons/components/external/: xml-commons provides an Apache-hosted set of DOM, SAX, and JAXP interfaces for use in other xml-based projects. Our hope is that we can standardize on both a common version and packaging scheme for these critical XML standards interfaces to make the lives of both our developers and users easier. The External Components portion of xml-commons contains interfaces that are defined by external standards organizations. For DOM, that's the W3C; for SAX it's David Megginson and sax.sourceforge.net; for JAXP it's Sun. 
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// $Id: DocumentBuilder.java 584483 2007-10-14 02:54:48Z mrglavas $

package javax.xml.parsers;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;

import javax.xml.validation.Schema;

import org.w3c.dom.Document;
import org.w3c.dom.DOMImplementation;

import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;


Defines the API to obtain DOM Document instances from an XML document. Using this class, an application programmer can obtain a Document from XML.
 An instance of this class can be obtained from the DocumentBuilderFactory.newDocumentBuilder() method. Once an instance of this class is obtained, XML can be parsed from a variety of input sources. These input sources are InputStreams, Files, URLs, and SAX InputSources.

Note that this class reuses several classes from the SAX API. This
does not require that the implementor of the underlying DOM
implementation use a SAX parser to parse XML document into a
Document. It merely requires that the implementation
communicate with the application using these existing APIs.

Author:Jeff Suttor
Version:$Revision: 584483 $, $Date: 2007-10-13 22:54:48 -0400 (Sat, 13 Oct 2007) $
/**
 * Defines the API to obtain DOM Document instances from an XML
 * document. Using this class, an application programmer can obtain a
 * {@link Document} from XML.<p>
 *
 * An instance of this class can be obtained from the
 * {@link DocumentBuilderFactory#newDocumentBuilder()} method. Once
 * an instance of this class is obtained, XML can be parsed from a
 * variety of input sources. These input sources are InputStreams,
 * Files, URLs, and SAX InputSources.<p>
 *
 * Note that this class reuses several classes from the SAX API. This
 * does not require that the implementor of the underlying DOM
 * implementation use a SAX parser to parse XML document into a
 * <code>Document</code>. It merely requires that the implementation
 * communicate with the application using these existing APIs.
 *
 * @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
 * @version $Revision: 584483 $, $Date: 2007-10-13 22:54:48 -0400 (Sat, 13 Oct 2007) $
 */

public abstract class DocumentBuilder {
    
    private static final boolean DEBUG = false;
    
    
Protected constructor 
/** Protected constructor */
    protected DocumentBuilder () {
    }

	
Reset this DocumentBuilder to its original configuration.


DocumentBuilder is reset to the same state as when it was created with DocumentBuilderFactory.newDocumentBuilder(). reset() is designed to allow the reuse of existing DocumentBuilders
thus saving resources associated with the creation of new DocumentBuilders.


The reset DocumentBuilder is not guaranteed to have the same EntityResolver or ErrorHandler Objects, e.g. Object.equals(Object obj). It is guaranteed to have a functionally equal EntityResolver and ErrorHandler.


Since:1.5
/**
	  * <p>Reset this <code>DocumentBuilder</code> to its original configuration.</p>
	  * 
	  * <p><code>DocumentBuilder</code> is reset to the same state as when it was created with
	  * {@link DocumentBuilderFactory#newDocumentBuilder()}.
	  * <code>reset()</code> is designed to allow the reuse of existing <code>DocumentBuilder</code>s
	  * thus saving resources associated with the creation of new <code>DocumentBuilder</code>s.</p>
	  * 
	  * <p>The reset <code>DocumentBuilder</code> is not guaranteed to have the same {@link EntityResolver} or {@link ErrorHandler}
	  * <code>Object</code>s, e.g. {@link Object#equals(Object obj)}.  It is guaranteed to have a functionally equal
	  * <code>EntityResolver</code> and <code>ErrorHandler</code>.</p>
	  * 
	  * @since 1.5
	  */
	public void reset() {
	
		// implementors should override this method
		throw new UnsupportedOperationException(
			"This DocumentBuilder, \"" + this.getClass().getName() + "\", does not support the reset functionality."
			+ "  Specification \"" + this.getClass().getPackage().getSpecificationTitle() + "\""
			+ " version \"" + this.getClass().getPackage().getSpecificationVersion() + "\""
			);
	}

    
Parse the content of the given InputStream as an XML document and return a new DOM Document object. An IllegalArgumentException is thrown if the
InputStream is null.

Params:
  • is – InputStream containing the content to be parsed.
Throws:
See Also:
Returns:Document result of parsing the
 InputStream
/**
     * Parse the content of the given <code>InputStream</code> as an XML
     * document and return a new DOM {@link Document} object.
     * An <code>IllegalArgumentException</code> is thrown if the
     * <code>InputStream</code> is null.
     *
     * @param is InputStream containing the content to be parsed.
     * @return <code>Document</code> result of parsing the
     *  <code>InputStream</code>
     * @exception IOException If any IO errors occur.
     * @exception SAXException If any parse errors occur.
     * @see org.xml.sax.DocumentHandler
     */
    
    public Document parse(InputStream is)
        throws SAXException, IOException {
        if (is == null) {
            throw new IllegalArgumentException("InputStream cannot be null");
        }
        
        InputSource in = new InputSource(is);
        return parse(in);
    }

    
Parse the content of the given InputStream as an XML document and return a new DOM Document object. An IllegalArgumentException is thrown if the
InputStream is null.

Params:
  • is – InputStream containing the content to be parsed.
  • systemId – Provide a base for resolving relative URIs.
Throws:
See Also:
Returns:A new DOM Document object.
/**
     * Parse the content of the given <code>InputStream</code> as an
     * XML document and return a new DOM {@link Document} object.
     * An <code>IllegalArgumentException</code> is thrown if the
     * <code>InputStream</code> is null.
     *
     * @param is InputStream containing the content to be parsed.
     * @param systemId Provide a base for resolving relative URIs.
     * @return A new DOM Document object.
     * @exception IOException If any IO errors occur.
     * @exception SAXException If any parse errors occur.
     * @see org.xml.sax.DocumentHandler
     */
    
    public Document parse(InputStream is, String systemId)
        throws SAXException, IOException {
        if (is == null) {
            throw new IllegalArgumentException("InputStream cannot be null");
        }
        
        InputSource in = new InputSource(is);
        in.setSystemId(systemId);
        return parse(in);
    }

    
Parse the content of the given URI as an XML document and return a new DOM Document object. An IllegalArgumentException is thrown if the
URI is null null.

Params:
  • uri – The location of the content to be parsed.
Throws:
See Also:
Returns:A new DOM Document object.
/**
     * Parse the content of the given URI as an XML document
     * and return a new DOM {@link Document} object.
     * An <code>IllegalArgumentException</code> is thrown if the
     * URI is <code>null</code> null.
     *
     * @param uri The location of the content to be parsed.
     * @return A new DOM Document object.
     * @exception IOException If any IO errors occur.
     * @exception SAXException If any parse errors occur.
     * @see org.xml.sax.DocumentHandler
     */
    
    public Document parse(String uri)
        throws SAXException, IOException {
        if (uri == null) {
            throw new IllegalArgumentException("URI cannot be null");
        }
        
        InputSource in = new InputSource(uri);
        return parse(in);
    }

    
Parse the content of the given file as an XML document and return a new DOM Document object. An IllegalArgumentException is thrown if the
File is null null.

Params:
  • f – The file containing the XML to parse.
Throws:
See Also:
Returns:A new DOM Document object.
/**
     * Parse the content of the given file as an XML document
     * and return a new DOM {@link Document} object.
     * An <code>IllegalArgumentException</code> is thrown if the
     * <code>File</code> is <code>null</code> null.
     *
     * @param f The file containing the XML to parse.
     * @exception IOException If any IO errors occur.
     * @exception SAXException If any parse errors occur.
     * @see org.xml.sax.DocumentHandler
     * @return A new DOM Document object.
     */
    
    public Document parse(File f) throws SAXException, IOException {
        if (f == null) {
            throw new IllegalArgumentException("File cannot be null");
        }
        
        String escapedURI = FilePathToURI.filepath2URI(f.getAbsolutePath());
        
        if (DEBUG) {
            System.out.println("Escaped URI = " + escapedURI);
        }

        InputSource in = new InputSource(escapedURI);
        return parse(in);
    }

    
Parse the content of the given input source as an XML document and return a new DOM Document object. An IllegalArgumentException is thrown if the
InputSource is null null.

Params:
  • is – InputSource containing the content to be parsed.
Throws:
See Also:
Returns:A new DOM Document object.
/**
     * Parse the content of the given input source as an XML document
     * and return a new DOM {@link Document} object.
     * An <code>IllegalArgumentException</code> is thrown if the
     * <code>InputSource</code> is <code>null</code> null.
     *
     * @param is InputSource containing the content to be parsed.
     * @exception IOException If any IO errors occur.
     * @exception SAXException If any parse errors occur.
     * @see org.xml.sax.DocumentHandler
     * @return A new DOM Document object.
     */
    
    public abstract Document parse(InputSource is)
        throws  SAXException, IOException;

    
    
Indicates whether or not this parser is configured to
understand namespaces.

Returns:true if this parser is configured to understand
        namespaces; false otherwise.
/**
     * Indicates whether or not this parser is configured to
     * understand namespaces.
     *
     * @return true if this parser is configured to understand
     *         namespaces; false otherwise.
     */

    public abstract boolean isNamespaceAware();

    
Indicates whether or not this parser is configured to
validate XML documents.

Returns:true if this parser is configured to validate
        XML documents; false otherwise.
/**
     * Indicates whether or not this parser is configured to
     * validate XML documents.
     *
     * @return true if this parser is configured to validate
     *         XML documents; false otherwise.
     */
    
    public abstract boolean isValidating();

    
Specify the EntityResolver to be used to resolve entities present in the XML document to be parsed. Setting this to null will result in the underlying
implementation using it's own default implementation and
behavior.

Params:
  • er – The EntityResolver to be used to resolve entities
          present in the XML document to be parsed.
/**
     * Specify the {@link EntityResolver} to be used to resolve
     * entities present in the XML document to be parsed. Setting
     * this to <code>null</code> will result in the underlying
     * implementation using it's own default implementation and
     * behavior.
     *
     * @param er The <code>EntityResolver</code> to be used to resolve entities
     *           present in the XML document to be parsed.
     */

    public abstract void setEntityResolver(EntityResolver er);

    
Specify the ErrorHandler to be used by the parser. Setting this to null will result in the underlying
implementation using it's own default implementation and
behavior.

Params:
  • eh – The ErrorHandler to be used by the parser.
/**
     * Specify the {@link ErrorHandler} to be used by the parser.
     * Setting this to <code>null</code> will result in the underlying
     * implementation using it's own default implementation and
     * behavior.
     *
     * @param eh The <code>ErrorHandler</code> to be used by the parser.
     */

    public abstract void setErrorHandler(ErrorHandler eh);

    
Obtain a new instance of a DOM Document object to build a DOM tree with. 
Returns:A new instance of a DOM Document object.
/**
     * Obtain a new instance of a DOM {@link Document} object
     * to build a DOM tree with.
     *
     * @return A new instance of a DOM Document object.
     */
    
    public abstract Document newDocument();

    
Obtain an instance of a DOMImplementation object. 
Returns:A new instance of a DOMImplementation.
/**
     * Obtain an instance of a {@link DOMImplementation} object.
     *
     * @return A new instance of a <code>DOMImplementation</code>.
     */

    public abstract DOMImplementation getDOMImplementation();
    
    
Get a reference to the the Schema being used by the XML processor.


If no schema is being used, null is returned.


Throws:
  • UnsupportedOperationException – 
     For backward compatibility, when implementations for
     earlier versions of JAXP is used, this exception will be
     thrown.
Returns:Schema being used or null
 if none in use
Since:1.5
/** <p>Get a reference to the the {@link Schema} being used by
     * the XML processor.</p>
     *
     * <p>If no schema is being used, <code>null</code> is returned.</p>
     *
     * @return {@link Schema} being used or <code>null</code>
     *  if none in use
     * 
     * @throws UnsupportedOperationException
     *      For backward compatibility, when implementations for
     *      earlier versions of JAXP is used, this exception will be
     *      thrown.
     * 
     * @since 1.5
     */
    public Schema getSchema() {
        throw new UnsupportedOperationException(
            "This parser does not support specification \""
            + this.getClass().getPackage().getSpecificationTitle()
            + "\" version \""
            + this.getClass().getPackage().getSpecificationVersion()
            + "\""
            );
    }
    
    
    
Get the XInclude processing mode for this parser.


Throws:
  • UnsupportedOperationException – 
     For backward compatibility, when implementations for
     earlier versions of JAXP is used, this exception will be
     thrown.
See Also:
Returns: the return value of the DocumentBuilderFactory.isXIncludeAware() when this parser was created from factory.
Since:1.5
/**
     * <p>Get the XInclude processing mode for this parser.</p>
     * 
     * @return

     *      the return value of
     *      the {@link DocumentBuilderFactory#isXIncludeAware()}
     *      when this parser was created from factory.
     * 
     * @throws UnsupportedOperationException
     *      For backward compatibility, when implementations for
     *      earlier versions of JAXP is used, this exception will be
     *      thrown.
     * 
     * @since 1.5
     * 
     * @see DocumentBuilderFactory#setXIncludeAware(boolean)
     */
    public boolean isXIncludeAware() {
        throw new UnsupportedOperationException(
            "This parser does not support specification \""
            + this.getClass().getPackage().getSpecificationTitle()
            + "\" version \""
            + this.getClass().getPackage().getSpecificationVersion()
            + "\""
            );
    }
}