DefaultNonBlockingXMLReader.java

/*
 *  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.
 *
 */
package org.apache.vysper.xml.sax.impl;

import java.io.IOException;
import java.nio.charset.CharsetDecoder;
import java.util.HashMap;
import java.util.Map;

import org.apache.mina.core.buffer.IoBuffer;
import org.apache.vysper.xml.sax.NonBlockingXMLReader;
import org.xml.sax.ContentHandler;
import org.xml.sax.DTDHandler;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
import org.xml.sax.helpers.DefaultHandler;

/**
 * @author The Apache MINA Project (dev@mina.apache.org)
 */
public class DefaultNonBlockingXMLReader implements NonBlockingXMLReader {

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

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

    public static final String FEATURE_COMMENTS_ALLOWED = "http://mina.apache.org/vysper/features/comments-allowed";

    public static final String FEATURE_RESTART_ALLOWED = "http://mina.apache.org/vysper/features/restart-allowed";

    public static final String PROPERTY_RESTART_QNAME = "http://mina.apache.org/vysper/properties/restart-qname";

    private ErrorHandler errorHandler = new DefaultHandler();

    private ContentHandler contentHandler = new DefaultHandler();

    private XMLParser parser;

    private Map<String, Boolean> features = new HashMap<String, Boolean>();

    private Map<String, Object> properties = new HashMap<String, Object>();

    public DefaultNonBlockingXMLReader() {
        // set default features
        features.put(FEATURE_NAMESPACES, true);
        features.put(FEATURE_NAMESPACE_PREFIXES, false);
        features.put(FEATURE_COMMENTS_ALLOWED, true);
        features.put(FEATURE_RESTART_ALLOWED, false);
    }

    /**
     * {@inheritDoc}
     */
    public boolean getFeature(String name) throws SAXNotRecognizedException, SAXNotSupportedException {
        if (features.containsKey(name)) {
            return features.get(name);
        } else {
            throw new SAXNotRecognizedException("Unknown feature");
        }
    }

    /**
     * {@inheritDoc}
     */
    public void setFeature(String name, boolean value) throws SAXNotRecognizedException, SAXNotSupportedException {

        // features must be set before parsing starts
        if (parser != null) {
            throw new SAXNotSupportedException("Feature can not be set during parsing");
        }

        if (features.containsKey(name)) {
            // TODO make configurable features and values easier to manage
            if (name.equals(FEATURE_NAMESPACES) && value) {
                // ok
            } else if (name.equals(FEATURE_NAMESPACE_PREFIXES)) {
                features.put(FEATURE_NAMESPACE_PREFIXES, value);
            } else if (name.equals(FEATURE_COMMENTS_ALLOWED)) {
                features.put(FEATURE_COMMENTS_ALLOWED, value);
            } else if (name.equals(FEATURE_RESTART_ALLOWED)) {
                features.put(FEATURE_RESTART_ALLOWED, value);
            } else {
                throw new SAXNotSupportedException("Not supported");
            }
        } else {
            throw new SAXNotRecognizedException("Unknown feature");
        }
    }

    /**
     * {@inheritDoc}
     */
    public Object getProperty(String name) throws SAXNotRecognizedException, SAXNotSupportedException {
        return properties.get(name);
    }

    /**
     * {@inheritDoc}
     */
    public void setProperty(String name, Object value) throws SAXNotRecognizedException, SAXNotSupportedException {
        properties.put(name, value);
    }

    /**
     * {@inheritDoc}
     */
    public void setEntityResolver(EntityResolver resolver) {
        throw new RuntimeException("Entity resolver not supported");
    }

    /**
     * {@inheritDoc}
     */
    public EntityResolver getEntityResolver() {
        throw new RuntimeException("Entity resolver not supported");
    }

    /**
     * {@inheritDoc}
     */
    public void setDTDHandler(DTDHandler handler) {
        throw new RuntimeException("DTD handler not supported");
    }

    public DTDHandler getDTDHandler() {
        throw new RuntimeException("DTD handler not supported");
    }

    /**
     * {@inheritDoc}
     */
    public void setContentHandler(ContentHandler handler) {
        this.contentHandler = handler;
    }

    /**
     * {@inheritDoc}
     */
    public ContentHandler getContentHandler() {
        return contentHandler;
    }

    /**
     * {@inheritDoc}
     */
    public void setErrorHandler(ErrorHandler handler) {
        this.errorHandler = handler;
    }

    /**
     * {@inheritDoc}
     */
    public ErrorHandler getErrorHandler() {
        return errorHandler;
    }

    /**
     * {@inheritDoc}
     */
    public void parse(IoBuffer buffer, CharsetDecoder decoder) throws IOException, SAXException {
        if (parser == null) {
            parser = new XMLParser(contentHandler, errorHandler, features, properties);
        }

        parser.parse(buffer, decoder);
    }

}