fm.last.moji.impl.GetInputStreamCommand.java Source code

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Here is the source code for fm.last.moji.impl.GetInputStreamCommand.java

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/*
 * Copyright 2012 Last.fm
 *
 *  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 fm.last.moji.impl;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
import java.util.concurrent.locks.Lock;

import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import fm.last.moji.tracker.Tracker;

class GetInputStreamCommand implements MojiCommand {

    private static final Logger log = LoggerFactory.getLogger(GetInputStreamCommand.class);

    final String key;
    final String domain;
    private final HttpConnectionFactory httpFactory;
    private final Lock readLock;
    private InputStream stream;

    GetInputStreamCommand(String key, String domain, HttpConnectionFactory httpFactory, Lock readLock) {
        this.key = key;
        this.domain = domain;
        this.httpFactory = httpFactory;
        this.readLock = readLock;
    }

    @Override
    public void executeWithTracker(Tracker tracker) throws IOException {
        List<URL> paths = tracker.getPaths(key, domain);
        if (paths.isEmpty()) {
            throw new FileNotFoundException("key=" + key + ", domain=" + domain);
        }
        IOException lastException = null;
        for (URL path : paths) {
            try {
                log.debug("Opened: {}", path);
                HttpURLConnection urlConnection = httpFactory.newConnection(path);
                stream = new FileDownloadInputStream(urlConnection.getInputStream(), readLock);
                return;
            } catch (IOException e) {
                log.debug("Failed to open input -> {}", path);
                log.debug("Exception was: ", e);
                lastException = e;
                IOUtils.closeQuietly(stream);
            }
        }
        throw lastException;
    }

    InputStream getInputStream() {
        return stream;
    }

    @Override
    public String toString() {
        StringBuilder builder = new StringBuilder();
        builder.append("GetInputStreamCommand [domain=");
        builder.append(domain);
        builder.append(", key=");
        builder.append(key);
        builder.append("]");
        return builder.toString();
    }

}