DXF2SVGGenerator.java

/*******************************************************************************
 * Copyright 2010 Simon Mieth
 * 
 * Licensed 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.kabeja.cocoon.generation;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;

import org.apache.avalon.framework.logger.Logger;
import org.apache.avalon.framework.parameters.ParameterException;
import org.apache.avalon.framework.parameters.Parameterizable;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.caching.CacheableProcessingComponent;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.generation.AbstractGenerator;
import org.apache.cocoon.util.HashUtil;
import org.apache.excalibur.source.Source;
import org.apache.excalibur.source.SourceValidity;
import org.apache.excalibur.source.impl.validity.TimeStampValidity;
import org.kabeja.dxf.DXFDocument;
import org.kabeja.dxf.parser.DXFParser;
import org.kabeja.parser.Handler;
import org.kabeja.parser.ParseException;
import org.kabeja.parser.Parser;
import org.kabeja.parser.ParserBuilder;
import org.kabeja.parser.SAXParserBuilder;
import org.kabeja.svg.SVGGenerator;
import org.kabeja.xml.SAXGenerator;
import org.xml.sax.SAXException;


/**
 * This generator parses DXF-Sources and transform the data to SVG.
 *
 * @author <a href="mailto:simon.mieth@gmx.de">Simon Mieth</a>
 *
 */
public class DXF2SVGGenerator extends AbstractGenerator
    implements CacheableProcessingComponent, Parameterizable {
    public final static String PARAMETER_CONFIG = "configfile";
    public final static String PARAMETER_ENCODING = "encoding";
    private SourceResolver resolver;
    private String src;
    protected Source inputSource;
    protected String config = null;
    protected boolean configured = false;
    protected Logger log;
    protected Parser parser;
    protected String encoding;

    /*
     * (non-Javadoc)
     *
     * @see org.apache.cocoon.sitemap.SitemapModelComponent#setup(org.apache.cocoon.environment.SourceResolver,
     *      java.util.Map, java.lang.String,
     *      org.apache.avalon.framework.parameters.Parameters)
     */
    public void setup(SourceResolver resolver, Map objectModel, String src,
        Parameters par) throws ProcessingException, SAXException, IOException {
        super.setup(resolver, objectModel, src, par);

        // this is what we need
        this.resolver = resolver;
        this.src = src;
        this.inputSource = resolver.resolveURI(src);

        if (par.isParameter(PARAMETER_ENCODING)) {
            try {
                this.encoding = par.getParameter(PARAMETER_ENCODING);
            } catch (ParameterException e) {
                log.error("Setting up encoding error:" + e.getMessage());
                this.encoding = DXFParser.DEFAULT_ENCODING;
            }
        } else {
            this.encoding = DXFParser.DEFAULT_ENCODING;
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.cocoon.generation.Generator#generate()
     */
    public void generate()
        throws IOException, SAXException, ProcessingException {
        try {
            this.parser.parse(this.inputSource.getInputStream(), this.encoding);

            DXFDocument doc = parser.getDocument();

            // the xmlConsumer the next component in
            // the pipeline from parent class
            SAXGenerator generator = new SVGGenerator();
            generator.setProperties(new HashMap());
            generator.generate(doc, this.xmlConsumer, null);

            // all is done release the source
            this.resolver.release(this.inputSource);

            // a little help for the GC
            ((Handler) this.parser).releaseDXFDocument();

            doc = null;
        } catch (ParseException e) {
            throw new ProcessingException(e);
        } catch (IOException e) {
            throw new ProcessingException(e);
        }
    }

    public Serializable getKey() {
        // the key the sourc-uri this is unique
        if (this.inputSource.getLastModified() != 0) {
            return new Long(HashUtil.hash(this.inputSource.getURI()));
        }

        return new Long(0);
    }

    public SourceValidity getValidity() {
        // the validity is simple the last modified timestamp
        long modified = this.inputSource.getLastModified();

        return new TimeStampValidity(modified);
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.avalon.framework.logger.LogEnabled#enableLogging(org.apache.avalon.framework.logger.Logger)
     */
    public void enableLogging(Logger log) {
        this.log = log;
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.avalon.framework.parameters.Parameterizable#parameterize(org.apache.avalon.framework.parameters.Parameters)
     */
    public void parameterize(Parameters params) throws ParameterException {
        if (params.isParameter(PARAMETER_CONFIG)) {
            try {
                this.initParser(params.getParameter(PARAMETER_CONFIG));
            } catch (Exception e) {
                log.error("Configuration failed:" + e.getMessage());
                throw new ParameterException("DXFParserConfiguration");
            }
        } else {
            initParser();
        }
    }

    protected void initParser() {
        this.parser = ParserBuilder.createDefaultParser();
    }

    protected void initParser(String config) throws Exception {
        // TODO use the sourceresolver
        this.parser = SAXParserBuilder.buildFromStream(new FileInputStream(
                    config));
    }
}