org.jage.platform.config.xml.loaders.RawDocumentLoader.java Source code

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Here is the source code for org.jage.platform.config.xml.loaders.RawDocumentLoader.java

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/**
 * Copyright (C) 2006 - 2012
 *   Pawel Kedzior
 *   Tomasz Kmiecik
 *   Kamil Pietak
 *   Krzysztof Sikora
 *   Adam Wos
 *   Lukasz Faber
 *   Daniel Krzywicki
 *   and other students of AGH University of Science and Technology.
 *
 * This file is part of AgE.
 *
 * AgE is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * AgE is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with AgE.  If not, see <http://www.gnu.org/licenses/>.
 */
/*
 * Created: 2012-01-28
 * $Id: RawDocumentLoader.java 471 2012-10-30 11:17:00Z faber $
 */

package org.jage.platform.config.xml.loaders;

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

import static java.lang.String.format;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.io.SAXReader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;

import org.jage.platform.component.definition.ConfigurationException;
import org.jage.util.io.IncorrectUriException;
import org.jage.util.io.Resource;
import org.jage.util.io.ResourceLoader;

import com.google.common.io.Closeables;

/**
 * Loads a raw DOM document from the provided resource path. Uses {@link ResourceLoader} to locate the actual resource.
 * It does not requires any delegate and should typically be used as the head of the chain.
 *
 * @author AGH AgE Team
 */
public final class RawDocumentLoader extends AbstractDocumentLoader {

    private static final Logger LOG = LoggerFactory.getLogger(RawDocumentLoader.class);

    private final SAXReader reader;

    /**
     * Creates a {@link RawDocumentLoader}.
     *
     * @throws ConfigurationException if an error happens when configuring the SAXReader.
     */
    public RawDocumentLoader() throws ConfigurationException {
        try {
            SAXParserFactory factory = SAXParserFactory.newInstance();
            factory.setValidating(true);

            SAXParser parser = factory.newSAXParser();
            parser.setProperty("http://java.sun.com/xml/jaxp/properties/schemaLanguage",
                    "http://www.w3.org/2001/XMLSchema");
            parser.setProperty("http://java.sun.com/xml/jaxp/properties/schemaSource",
                    getClass().getClassLoader().getResourceAsStream("age.xsd"));

            reader = new SAXReader(parser.getXMLReader());
            reader.setValidation(true);

        } catch (final ParserConfigurationException e) {
            throw newConfigurationException(e);
        } catch (final SAXException e) {
            throw newConfigurationException(e);
        }
    }

    @Override
    public Document loadDocument(final String path) throws ConfigurationException {
        InputStream input = null;
        try {
            final Resource resource = ResourceLoader.getResource(path);
            input = resource.getInputStream();
            reader.setErrorHandler(new AgEXmlErrorHandler(path));
            return reader.read(input);
        } catch (final IncorrectUriException e) {
            throw new ConfigurationException("Could not locate resource with path " + path, e);
        } catch (final IOException e) {
            throw new ConfigurationException("Could not open resource with path " + path, e);
        } catch (final DocumentException e) {
            throw new ConfigurationException("Could not read resource with path " + path, e);
        } finally {
            Closeables.closeQuietly(input);
        }
    }

    private ConfigurationException newConfigurationException(final Exception e) throws ConfigurationException {
        return new ConfigurationException("Could not instantiate loader", e);
    }

    /**
     * Custom error handler.
     *
     * @author AGH AgE Team
     */
    private static final class AgEXmlErrorHandler implements ErrorHandler {

        private final String path;

        private AgEXmlErrorHandler(final String path) {
            this.path = path;
        }

        @Override
        public void warning(final SAXParseException e) throws SAXException {
            LOG.warn(createLogString(e));
            throw e;
        }

        @Override
        public void error(final SAXParseException e) throws SAXException {
            LOG.error(createLogString(e));
            throw e;
        }

        @Override
        public void fatalError(final SAXParseException e) throws SAXException {
            LOG.error(createLogString(e));
            throw e;
        }

        private String createLogString(final SAXParseException e) {
            return format("'%s':%s:%s: %s", path, e.getLineNumber(), e.getColumnNumber(),
                    cleanMessage(e.getMessage()));
        }

        private String cleanMessage(final String message) {
            final String[] split = message.split(":");
            final String cleanedMessage = split.length > 1 ? split[1] : split[0];
            return cleanedMessage.trim();
        }
    }
}