saxwriter.java

解决如何把XML应用到JAVA里问题

/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package org.dom4j.io;

import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.dom4j.Attribute;
import org.dom4j.Branch;
import org.dom4j.CDATA;
import org.dom4j.CharacterData;
import org.dom4j.Comment;
import org.dom4j.Document;
import org.dom4j.DocumentType;
import org.dom4j.Element;
import org.dom4j.Entity;
import org.dom4j.Namespace;
import org.dom4j.Node;
import org.dom4j.ProcessingInstruction;
import org.dom4j.Text;
import org.dom4j.tree.NamespaceStack;

import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.DTDHandler;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
import org.xml.sax.XMLReader;
import org.xml.sax.ext.LexicalHandler;
import org.xml.sax.helpers.AttributesImpl;
import org.xml.sax.helpers.LocatorImpl;

/**
 * <p>
 * <code>SAXWriter</code> writes a DOM4J tree to a SAX ContentHandler.
 * </p>
 * 
 * @author <a href="mailto:[e-mail]">James Strachan </a>
 * @version $Revision: 1.24 $
 */
public class SAXWriter implements XMLReader {
    protected static final String[] LEXICAL_HANDLER_NAMES = {
            "http://xml.org/sax/properties/lexical-handler",
            "http://xml.org/sax/handlers/LexicalHandler" };

    protected static final String FEATURE_NAMESPACE_PREFIXES 
            = "http://xml.org/sax/features/namespace-prefixes";

    protected static final String FEATURE_NAMESPACES 
            = "http://xml.org/sax/features/namespaces";

    /** <code>ContentHandler</code> to which SAX events are raised */
    private ContentHandler contentHandler;

    /** <code>DTDHandler</code> fired when a document has a DTD */
    private DTDHandler dtdHandler;

    /** <code>EntityResolver</code> fired when a document has a DTD */
    private EntityResolver entityResolver;

    private ErrorHandler errorHandler;

    /** <code>LexicalHandler</code> fired on Entity and CDATA sections */
    private LexicalHandler lexicalHandler;

    /** <code>AttributesImpl</code> used when generating the Attributes */
    private AttributesImpl attributes = new AttributesImpl();

    /** Stores the features */
    private Map features = new HashMap();

    /** Stores the properties */
    private Map properties = new HashMap();

    /** Whether namespace declarations are exported as attributes or not */
    private boolean declareNamespaceAttributes;

    public SAXWriter() {
        properties.put(FEATURE_NAMESPACE_PREFIXES, Boolean.FALSE);
        properties.put(FEATURE_NAMESPACE_PREFIXES, Boolean.TRUE);
    }

    public SAXWriter(ContentHandler contentHandler) {
        this();
        this.contentHandler = contentHandler;
    }

    public SAXWriter(ContentHandler contentHandler,
            LexicalHandler lexicalHandler) {
        this();
        this.contentHandler = contentHandler;
        this.lexicalHandler = lexicalHandler;
    }

    public SAXWriter(ContentHandler contentHandler,
            LexicalHandler lexicalHandler, EntityResolver entityResolver) {
        this();
        this.contentHandler = contentHandler;
        this.lexicalHandler = lexicalHandler;
        this.entityResolver = entityResolver;
    }

    /**
     * A polymorphic method to write any Node to this SAX stream
     * 
     * @param node
     *            DOCUMENT ME!
     * 
     * @throws SAXException
     *             DOCUMENT ME!
     */
    public void write(Node node) throws SAXException {
        int nodeType = node.getNodeType();

        switch (nodeType) {
            case Node.ELEMENT_NODE:
                write((Element) node);

                break;

            case Node.ATTRIBUTE_NODE:
                write((Attribute) node);

                break;

            case Node.TEXT_NODE:
                write(node.getText());

                break;

            case Node.CDATA_SECTION_NODE:
                write((CDATA) node);

                break;

            case Node.ENTITY_REFERENCE_NODE:
                write((Entity) node);

                break;

            case Node.PROCESSING_INSTRUCTION_NODE:
                write((ProcessingInstruction) node);

                break;

            case Node.COMMENT_NODE:
                write((Comment) node);

                break;

            case Node.DOCUMENT_NODE:
                write((Document) node);

                break;

            case Node.DOCUMENT_TYPE_NODE:
                write((DocumentType) node);

                break;

            case Node.NAMESPACE_NODE:

                // Will be output with attributes
                // write((Namespace) node);
                break;

            default:
                throw new SAXException("Invalid node type: " + node);
        }
    }

    /**
     * Generates SAX events for the given Document and all its content
     * 
     * @param document
     *            is the Document to parse
     * 
     * @throws SAXException
     *             if there is a SAX error processing the events
     */
    public void write(Document document) throws SAXException {
        if (document != null) {
            checkForNullHandlers();

            documentLocator(document);
            startDocument();
            entityResolver(document);
            dtdHandler(document);

            writeContent(document, new NamespaceStack());
            endDocument();
        }
    }

    /**
     * Generates SAX events for the given Element and all its content
     * 
     * @param element
     *            is the Element to parse
     * 
     * @throws SAXException
     *             if there is a SAX error processing the events
     */
    public void write(Element element) throws SAXException {
        write(element, new NamespaceStack());
    }

    /**
     * <p>
     * Writes the opening tag of an {@link Element}, including its {@link
     * Attribute}s but without its content.
     * </p>
     * 
     * @param element
     *            <code>Element</code> to output.
     * 
     * @throws SAXException
     *             DOCUMENT ME!
     */
    public void writeOpen(Element element) throws SAXException {
        startElement(element, null);
    }

    /**
     * <p>
     * Writes the closing tag of an {@link Element}
     * </p>
     * 
     * @param element
     *            <code>Element</code> to output.
     * 
     * @throws SAXException
     *             DOCUMENT ME!
     */
    public void writeClose(Element element) throws SAXException {
        endElement(element);
    }

    /**
     * Generates SAX events for the given text
     * 
     * @param text
     *            is the text to send to the SAX ContentHandler
     * 
     * @throws SAXException
     *             if there is a SAX error processing the events
     */
    public void write(String text) throws SAXException {
        if (text != null) {
            char[] chars = text.toCharArray();
            contentHandler.characters(chars, 0, chars.length);
        }
    }

    /**
     * Generates SAX events for the given CDATA
     * 
     * @param cdata
     *            is the CDATA to parse
     * 
     * @throws SAXException
     *             if there is a SAX error processing the events
     */
    public void write(CDATA cdata) throws SAXException {
        String text = cdata.getText();

        if (lexicalHandler != null) {
            lexicalHandler.startCDATA();
            write(text);
            lexicalHandler.endCDATA();
        } else {
            write(text);
        }
    }

    /**
     * Generates SAX events for the given Comment
     * 
     * @param comment
     *            is the Comment to parse
     * 
     * @throws SAXException
     *             if there is a SAX error processing the events
     */
    public void write(Comment comment) throws SAXException {
        if (lexicalHandler != null) {
            String text = comment.getText();
            char[] chars = text.toCharArray();
            lexicalHandler.comment(chars, 0, chars.length);
        }
    }

    /**
     * Generates SAX events for the given Entity
     * 
     * @param entity
     *            is the Entity to parse
     * 
     * @throws SAXException
     *             if there is a SAX error processing the events
     */
    public void write(Entity entity) throws SAXException {
        String text = entity.getText();

        if (lexicalHandler != null) {
            String name = entity.getName();
            lexicalHandler.startEntity(name);
            write(text);
            lexicalHandler.endEntity(name);
        } else {
            write(text);
        }
    }

    /**
     * Generates SAX events for the given ProcessingInstruction
     * 
     * @param pi
     *            is the ProcessingInstruction to parse
     * 
     * @throws SAXException
     *             if there is a SAX error processing the events
     */
    public void write(ProcessingInstruction pi) throws SAXException {
        String target = pi.getTarget();
        String text = pi.getText();
        contentHandler.processingInstruction(target, text);
    }

    /**
     * Should namespace declarations be converted to "xmlns" attributes. This
     * property defaults to <code>false</code> as per the SAX specification.
     * This property is set via the SAX feature
     * "http://xml.org/sax/features/namespace-prefixes"
     * 
     * @return DOCUMENT ME!
     */
    public boolean isDeclareNamespaceAttributes() {
        return declareNamespaceAttributes;
    }

    /**
     * Sets whether namespace declarations should be exported as "xmlns"
     * attributes or not. This property is set from the SAX feature
     * "http://xml.org/sax/features/namespace-prefixes"
     * 
     * @param declareNamespaceAttrs
     *            DOCUMENT ME!
     */
    public void setDeclareNamespaceAttributes(boolean declareNamespaceAttrs) {
        this.declareNamespaceAttributes = declareNamespaceAttrs;
    }

    // XMLReader methods
    // -------------------------------------------------------------------------

    /**
     * DOCUMENT ME!
     * 
     * @return the <code>ContentHandler</code> called when SAX events are
     *         raised
     */
    public ContentHandler getContentHandler() {
        return contentHandler;
    }

    /**
     * Sets the <code>ContentHandler</code> called when SAX events are raised
     * 
     * @param contentHandler
     *            is the <code>ContentHandler</code> called when SAX events
     *            are raised
     */
    public void setContentHandler(ContentHandler contentHandler) {
        this.contentHandler = contentHandler;
    }

    /**
     * DOCUMENT ME!
     * 
     * @return the <code>DTDHandler</code>
     */
    public DTDHandler getDTDHandler() {
        return dtdHandler;
    }

    /**
     * Sets the <code>DTDHandler</code>.
     * 
     * @param handler
     *            DOCUMENT ME!
     */
    public void setDTDHandler(DTDHandler handler) {
        this.dtdHandler = handler;
    }

    /**
     * DOCUMENT ME!
     * 
     * @return the <code>ErrorHandler</code>
     */
    public ErrorHandler getErrorHandler() {
        return errorHandler;
    }

    /**
     * Sets the <code>ErrorHandler</code>.
     * 
     * @param errorHandler
     *            DOCUMENT ME!
     */
    public void setErrorHandler(ErrorHandler errorHandler) {
        this.errorHandler = errorHandler;
    }

    /**
     * DOCUMENT ME!
     * 
     * @return the <code>EntityResolver</code> used when a Document contains a
     *         DTD
     */
    public EntityResolver getEntityResolver() {
        return entityResolver;
    }

    /**
     * Sets the <code>EntityResolver</code>.
     * 
     * @param entityResolver
     *            is the <code>EntityResolver</code>
     */
    public void setEntityResolver(EntityResolver entityResolver) {
        this.entityResolver = entityResolver;
    }

    /**
     * DOCUMENT ME!
     * 
     * @return the <code>LexicalHandler</code> used when a Document contains a
     *         DTD
     */
    public LexicalHandler getLexicalHandler() {
        return lexicalHandler;
    }

    /**
     * Sets the <code>LexicalHandler</code>.
     * 
     * @param lexicalHandler
     *            is the <code>LexicalHandler</code>
     */
    public void setLexicalHandler(LexicalHandler lexicalHandler) {
        this.lexicalHandler = lexicalHandler;
    }

    /**
     * Sets the <code>XMLReader</code> used to write SAX events to
     * 
     * @param xmlReader
     *            is the <code>XMLReader</code>
     */