saxmodifier.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.File;
import java.io.InputStream;
import java.io.Reader;
import java.net.URL;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.DocumentFactory;

import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;

/**
 * The SAXModifier reads, modifies and writes XML documents using SAX.
 * 
 * <p>
 * Registered {@link ElementModifier}objects can provide modifications to (part
 * of) the xml tree, while the document is still being processed. This makes it
 * possible to change large xml documents without having them in memory.
 * </p>
 * 
 * <p>
 * The modified document is written when the {@link XMLWriter}is specified.
 * </p>
 * 
 * @author Wonne Keysers (Realsoftware.be)
 * 
 * @see org.dom4j.io.SAXReader
 * @see org.dom4j.io.XMLWriter
 */
public class SAXModifier {
    private XMLWriter xmlWriter;

    private XMLReader xmlReader;

    private boolean pruneElements;

    private SAXModifyReader modifyReader;

    private HashMap modifiers = new HashMap();

    /**
     * Creates a new modifier. <br>
     * The XMLReader to parse the source will be created via the
     * org.xml.sax.driver system property or JAXP if the system property is not
     * set.
     */
    public SAXModifier() {
    }

    /**
     * Creates a new modifier. <br>
     * The XMLReader to parse the source will be created via the
     * org.xml.sax.driver system property or JAXP if the system property is not
     * set.
     * 
     * @param pruneElements
     *            Set to true when the modified document must NOT be kept in
     *            memory.
     */
    public SAXModifier(boolean pruneElements) {
        this.pruneElements = pruneElements;
    }

    /**
     * Creates a new modifier that will the specified {@link
     * org.xml.sax.XMLReader} to parse the source.
     * 
     * @param xmlReader
     *            The XMLReader to use
     */
    public SAXModifier(XMLReader xmlReader) {
        this.xmlReader = xmlReader;
    }

    /**
     * Creates a new modifier that will the specified {@link
     * org.xml.sax.XMLReader} to parse the source.
     * 
     * @param xmlReader
     *            The XMLReader to use
     * @param pruneElements
     *            Set to true when the modified document must NOT be kept in
     *            memory.
     */
    public SAXModifier(XMLReader xmlReader, boolean pruneElements) {
        this.xmlReader = xmlReader;
    }

    /**
     * Reads a Document from the given {@link java.io.File}and writes it to the
     * specified {@link XMLWriter}using SAX. Registered {@linkElementModifier}
     * objects are invoked on the fly.
     * 
     * @param source
     *            is the <code>File</code> to read from.
     * 
     * @return the newly created Document instance
     * 
     * @throws DocumentException
     *             DocumentException org.dom4j.DocumentException} if an error
     *             occurs during parsing.
     */
    public Document modify(File source) throws DocumentException {
        try {
            return installModifyReader().read(source);
        } catch (SAXModifyException ex) {
            Throwable cause = ex.getCause();
            throw new DocumentException(cause.getMessage(), cause);
        }
    }

    /**
     * Reads a Document from the given {@link org.xml.sax.InputSource}and
     * writes it to the specified {@link XMLWriter}using SAX. Registered
     * {@link ElementModifier}objects are invoked on the fly.
     * 
     * @param source
     *            is the <code>org.xml.sax.InputSource</code> to read from.
     * 
     * @return the newly created Document instance
     * 
     * @throws DocumentException
     *             DocumentException org.dom4j.DocumentException} if an error
     *             occurs during parsing.
     */
    public Document modify(InputSource source) throws DocumentException {
        try {
            return installModifyReader().read(source);
        } catch (SAXModifyException ex) {
            Throwable cause = ex.getCause();
            throw new DocumentException(cause.getMessage(), cause);
        }
    }

    /**
     * Reads a Document from the given {@link java.io.InputStream}and writes it
     * to the specified {@link XMLWriter}using SAX. Registered {@link
     * ElementModifier} objects are invoked on the fly.
     * 
     * @param source
     *            is the <code>java.io.InputStream</code> to read from.
     * 
     * @return the newly created Document instance
     * 
     * @throws DocumentException
     *             DocumentException org.dom4j.DocumentException} if an error
     *             occurs during parsing.
     */
    public Document modify(InputStream source) throws DocumentException {
        try {
            return installModifyReader().read(source);
        } catch (SAXModifyException ex) {
            Throwable cause = ex.getCause();
            throw new DocumentException(cause.getMessage(), cause);
        }
    }

    /**
     * Reads a Document from the given {@link java.io.InputStream}and writes it
     * to the specified {@link XMLWriter}using SAX. Registered {@link
     * ElementModifier} objects are invoked on the fly.
     * 
     * @param source
     *            is the <code>java.io.InputStream</code> to read from.
     * @param systemId
     *            DOCUMENT ME!
     * 
     * @return the newly created Document instance
     * 
     * @throws DocumentException
     *             DocumentException org.dom4j.DocumentException} if an error
     *             occurs during parsing.
     */
    public Document modify(InputStream source, String systemId)
            throws DocumentException {
        try {
            return installModifyReader().read(source);
        } catch (SAXModifyException ex) {
            Throwable cause = ex.getCause();
            throw new DocumentException(cause.getMessage(), cause);
        }
    }

    /**
     * Reads a Document from the given {@link java.io.Reader}and writes it to
     * the specified {@link XMLWriter}using SAX. Registered {@link
     * ElementModifier} objects are invoked on the fly.
     * 
     * @param source
     *            is the <code>java.io.Reader</code> to read from.
     * 
     * @return the newly created Document instance
     * 
     * @throws DocumentException
     *             DocumentException org.dom4j.DocumentException} if an error
     *             occurs during parsing.
     */
    public Document modify(Reader source) throws DocumentException {
        try {
            return installModifyReader().read(source);
        } catch (SAXModifyException ex) {
            Throwable cause = ex.getCause();
            throw new DocumentException(cause.getMessage(), cause);
        }
    }

    /**
     * Reads a Document from the given {@link java.io.Reader}and writes it to
     * the specified {@link XMLWriter}using SAX. Registered {@link
     * ElementModifier} objects are invoked on the fly.
     * 
     * @param source
     *            is the <code>java.io.Reader</code> to read from.
     * @param systemId
     *            DOCUMENT ME!
     *