com.comcast.viper.hlsparserj.PlaylistFactory.java Source code

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Here is the source code for com.comcast.viper.hlsparserj.PlaylistFactory.java

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/**
 * Copyright 2015 Comcast Cable Communications Management, LLC
 *
 * 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.
 */
/**
 * TO-DO:
 * Add tests for: byte range, allow cache, iframes only, discontinuity
 * Create objects for: ext-x-map, ext-x-i-frame-stream-inf, ext-x-start, ext-x-discontinuity-sequence
 */
package com.comcast.viper.hlsparserj;

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;

import org.apache.http.HttpStatus;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;

import com.comcast.viper.hlsparserj.v12.MasterPlaylistV12;
import com.comcast.viper.hlsparserj.v12.MediaPlaylistV12;

/**
 * Provides factory methods to generate and parse playlists.
 */
public class PlaylistFactory {

    static {
        try {
            Class.forName("com.comcast.viper.hlsparserj.tags.TagNames");
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

    /**
     * Factory method to generate a playlist object. This method performs no
     * HTTP actions. It uses the playlistStream parameter as the playlist.
     *
     * @param playlistVersion version of the playlist (V12 is the default)
     * @param playlistStream inputStream containing a correctly formatted playlist
     * @return parsed playlist
     * @throws IOException on parsing exception
     */
    public static AbstractPlaylist parsePlaylist(final PlaylistVersion playlistVersion,
            final InputStream playlistStream) throws IOException {
        PlaylistParser parser = new PlaylistParser();
        parser.parse(playlistStream);
        return getVersionSpecificPlaylist(parser, playlistVersion);
    }

    /**
     * Factory method to generate playlist object.  This method performs no
     * HTTP actions. It uses the playlistString parameter as the playlist.
     *
     * @param playlistVersion version of the playlist (V12 is the default)
     * @param playlistString string containing a correctly formatted playlist
     * @return parsed playlist
     */
    public static AbstractPlaylist parsePlaylist(final PlaylistVersion playlistVersion,
            final String playlistString) {
        PlaylistParser parser = new PlaylistParser();
        parser.parse(playlistString);
        return getVersionSpecificPlaylist(parser, playlistVersion);
    }

    /**
     * Factory method to generate playlist object. This method uses a very
     * simple HTTP client to download the URL passed by the playlistURL
     * parameters. This method should not be used for applications that require
     * high-performance, as the HTTP connection management is very basic. If
     * your application has high performance requirements us the parsePlaylist
     * method that takes an InputStream.
     *
     * @param playlistVersion version of the playlist (V12 is the default)
     * @param playlistURL URL pointing to a playlist
     * @return parsed playlist
     * @throws IOException on connection and parsing exceptions
     */
    public static AbstractPlaylist parsePlaylist(final PlaylistVersion playlistVersion, final URL playlistURL)
            throws IOException {
        HttpClientBuilder builder = HttpClientBuilder.create();
        CloseableHttpClient httpClient = builder.build();
        PlaylistParser parser = new PlaylistParser();

        try {
            InputStream playlistStream = getPlaylistInputStream(httpClient, playlistURL);
            parser.parse(playlistStream);
        } finally {
            httpClient.close();
        }

        return getVersionSpecificPlaylist(parser, playlistVersion);
    }

    /**
     * Returns a playlist that represents a specific object version of the playlist.
     * Currently, only V12 is supported.
     * @param parser playlist parser
     * @param playlistVersion preferred playlist version
     * @return playlist
     */
    private static AbstractPlaylist getVersionSpecificPlaylist(final PlaylistParser parser,
            final PlaylistVersion playlistVersion) {
        AbstractPlaylist playlist = null;

        switch (playlistVersion) {
        case TWELVE:
        case DEFAULT:
        default:
            if (parser.isMasterPlaylist()) {
                playlist = new MasterPlaylistV12(parser.getTags());
            } else {
                playlist = new MediaPlaylistV12(parser.getTags());
            }

            break;
        }

        return playlist;
    }

    /**
     * Returns a playlist inputStream given an httpClient and a URL.
     * @param httpClient http client
     * @param url URL to a playlist
     * @return inputStream
     * @throws IOException on HTTP connection exception
     */
    private static InputStream getPlaylistInputStream(final CloseableHttpClient httpClient, final URL url)
            throws IOException {
        HttpGet get = new HttpGet(url.toString());
        CloseableHttpResponse response = null;
        response = httpClient.execute(get);
        if (response == null) {
            throw new IOException("Request returned a null response");
        }
        if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {
            response.close();
            throw new IOException("Request returned a status code of " + response.getStatusLine().getStatusCode());
        }

        return response.getEntity().getContent();
    }
}