org.openestate.io.examples.TrovitReadingExample Maven / Gradle / Ivy

Go to download
/*
 * Copyright 2015-2016 OpenEstate.org.
 *
 * 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.openestate.io.examples;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import javax.xml.bind.JAXBException;
import javax.xml.parsers.ParserConfigurationException;
import org.apache.commons.lang3.StringUtils;
import org.apache.log4j.PropertyConfigurator;
import org.openestate.io.trovit.TrovitDocument;
import org.openestate.io.trovit.TrovitUtils;
import org.openestate.io.trovit.xml.Ad;
import org.openestate.io.trovit.xml.Trovit;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.xml.sax.SAXException;

/**
 * Example for reading Trovit XML feeds.
 * 
 * This example illustrates how to read Trovit XML feeds.
 *
 * @since 1.0
 * @author Andreas Rudolph
 */
public class TrovitReadingExample
{
  private final static Logger LOGGER = LoggerFactory.getLogger( TrovitReadingExample.class );
  private final static String PACKAGE = "/org/openestate/io/examples";

  /**
   * Start the example application.
   *
   * @param args
   * command line arguments
   */
  public static void main( String[] args )
  {
    // init logging
    PropertyConfigurator.configure(
      TrovitReadingExample.class.getResource( PACKAGE + "/log4j.properties" ) );

    // read example files, if no files were specified as command line arguments
    if (args.length<1)
    {
      try
      {
        read( TrovitReadingExample.class.getResourceAsStream( PACKAGE + "/trovit.xml" ) );
      }
      catch (Exception ex)
      {
        LOGGER.error( "Can't read example file!" );
        LOGGER.error( "> " + ex.getLocalizedMessage(), ex );
        System.exit( 2 );
      }
    }

    // read files, that were specified as command line arguments
    else
    {
      for (String arg : args)
      {
        try
        {
          read( new File( arg ) );
        }
        catch (Exception ex)
        {
          LOGGER.error( "Can't read file '" + arg + "'!" );
          LOGGER.error( "> " + ex.getLocalizedMessage(), ex );
          System.exit( 2 );
        }
      }
    }
  }

  /**
   * Read a {@link File} into a {@link TrovitDocument} and print some of its
   * content to console.
   *
   * @param xmlFile
   * the file to read
   *
   * @throws SAXException
   * if the file is not readable by the XML parser
   *
   * @throws IOException
   * if the file is not readable
   *
   * @throws ParserConfigurationException
   * if the XML parser is improperly configured
   *
   * @throws JAXBException
   * if XML conversion into Java objects failed
   */
  protected static void read( File xmlFile ) throws SAXException, IOException, ParserConfigurationException, JAXBException
  {
    LOGGER.info( "process file: " + xmlFile.getAbsolutePath() );
    if (!xmlFile.isFile())
    {
      LOGGER.warn( "> provided file is invalid" );
      return;
    }
    TrovitDocument doc = TrovitUtils.createDocument( xmlFile );
    if (doc==null)
    {
      LOGGER.warn( "> provided XML is not supported" );
    }
    else
    {
      printToConsole( doc );
    }
  }

  /**
   * Read a {@link InputStream} into a {@link TrovitDocument} and print some of
   * its content to console.
   *
   * @param xmlInputStream
   * the input stream to read
   *
   * @throws SAXException
   * if the file is not readable by the XML parser
   *
   * @throws IOException
   * if the file is not readable
   *
   * @throws ParserConfigurationException
   * if the XML parser is improperly configured
   *
   * @throws JAXBException
   * if XML conversion into Java objects failed
   */
  protected static void read( InputStream xmlInputStream ) throws SAXException, IOException, ParserConfigurationException, JAXBException
  {
    LOGGER.info( "process example file" );
    TrovitDocument doc = TrovitUtils.createDocument( xmlInputStream );
    if (doc==null)
    {
      LOGGER.warn( "> provided XML is not supported" );
    }
    else
    {
      printToConsole( doc );
    }
  }

  /**
   * Print some content of a {@link TrovitDocument} to console.
   *
   * @param doc
   * the document to process
   *
   * @throws JAXBException
   * if XML conversion into Java objects failed
   */
  protected static void printToConsole( TrovitDocument doc ) throws JAXBException
  {
    Trovit trovit = doc.toObject();

    // process ads
    for (Ad ad : trovit.getAd())
    {
      // get object nr
      String objectNr = StringUtils.trimToNull( ad.getId() );
      if (objectNr==null) objectNr = "???";

      // get object title
      String objectTitle = StringUtils.trimToNull( ad.getTitle() );
      if (objectTitle==null) objectTitle = "???";

      // print object informations to console
      LOGGER.info( "> found object '" + objectNr + "' "
        + "with title '" + objectTitle + "'" );
    }
  }
}