it.tidalwave.bluemarine2.musicbrainz.impl.DefaultMusicBrainzApi Maven / Gradle / Ivy
/*
* #%L
* *********************************************************************************************************************
*
* blueMarine2 - lightweight MediaCenter
* http://bluemarine.tidalwave.it - hg clone https://bitbucket.org/tidalwave/bluemarine2-src
* %%
* Copyright (C) 2015 - 2015 Tidalwave s.a.s. (http://tidalwave.it)
* %%
*
* *********************************************************************************************************************
*
* 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.
*
* *********************************************************************************************************************
*
* $Id$
*
* *********************************************************************************************************************
* #L%
*/
package it.tidalwave.bluemarine2.musicbrainz.impl;
import it.tidalwave.bluemarine2.musicbrainz.MusicBrainzApi;
import javax.annotation.Nonnull;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;
import org.musicbrainz.ns.mmd_2.Metadata;
import lombok.Cleanup;
import lombok.extern.slf4j.Slf4j;
/***********************************************************************************************************************
*
* http://code.google.com/p/musicbrainzws2-java/ is available with an unsuitable license (GPLv3).
*
* @author Fabrizio Giudici
* @version $Id$
*
**********************************************************************************************************************/
@Slf4j
public class DefaultMusicBrainzApi implements MusicBrainzApi
{
private long latestMusicBrainzAccessTime = 0;
/*******************************************************************************************************************
*
* {@inheritDoc}
*
******************************************************************************************************************/
@Nonnull
public Metadata getMusicBrainzEntity (final @Nonnull String entityType,
final @Nonnull String entityId,
final @Nonnull String includes)
throws IOException, JAXBException, InterruptedException
{
final JAXBContext context = JAXBContext.newInstance("org.musicbrainz.ns.mmd_2");
final Unmarshaller u = context.createUnmarshaller();
final String urlAsString = String.format("http://musicbrainz.org/ws/2/%s/%s%s",
entityType,
entityId,
includes);
throttle();
final URL url = new URL(urlAsString);
final URLConnection connection = url.openConnection();
connection.setRequestProperty("User-agent", "blueMarine2");
@Cleanup final InputStream is = connection.getInputStream();
return (org.musicbrainz.ns.mmd_2.Metadata)u.unmarshal(is);
}
/*******************************************************************************************************************
*
* See https://wiki.musicbrainz.org/XML_Web_Service/Rate_Limiting
*
******************************************************************************************************************/
private void throttle()
throws InterruptedException
{
final long now = System.currentTimeMillis();
final long delta = 1200 - (now - latestMusicBrainzAccessTime);
latestMusicBrainzAccessTime = now;
if (delta > 0)
{
log.info("Throttling: waiting for {} msec...", delta);
Thread.sleep(delta);
}
}
}