Исходный код

001/*
002 * Copyright (c) 2010, 2012, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation.  Oracle designates this
008 * particular file as subject to the "Classpath" exception as provided
009 * by Oracle in the LICENSE file that accompanied this code.
010 *
011 * This code is distributed in the hope that it will be useful, but WITHOUT
012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
014 * version 2 for more details (a copy is included in the LICENSE file that
015 * accompanied this code).
016 *
017 * You should have received a copy of the GNU General Public License version
018 * 2 along with this work; if not, write to the Free Software Foundation,
019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020 *
021 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
022 * or visit www.oracle.com if you need additional information or have any
023 * questions.
024 */
025
026package javafx.scene.media;
027
028import java.util.Collections;
029import java.util.Locale;
030import java.util.Map;
031
032/**
033 * A class representing a track contained in a media resource.
034 * A media resource may have multiple parallel tracks, such as a video
035 * track with several audio tracks in different languages. The types of tracks
036 * supported by the system may be inferred from the existing subclasses of this
037 * class. Not all media resources will contain a track of each supported type,
038 * and the time span of a given track need not be commensurate with the time
039 * span of the containing media.
040 */
041public abstract class Track {
042    /**
043     * The name of the track or <code>null</code> if the track is unnamed.
044     */
045    private String name;
046    private long trackID;   // opaque, unique track ID used by players to identify it
047    private Locale locale;
048    private Map<String,Object> metadata;
049
050    /**
051     * Retrieves the name of the track.
052     * @return the track name or <code>null</code>.
053     */
054    public final String getName() {
055        return name;
056    }
057
058    /**
059     * The {@link Locale} specifying the language and possibly the country that
060     * the <code>Track</code> contents are formatted for. For {@link AudioTrack}s
061     * this will be the language spoken, for {@link SubtitleTrack}s this will be
062     * the language presented in the captions. Not all <code>Track</code>s will
063     * have an associated language, in which case this method will return null.
064     * 
065     * @return the <code>Track</code>s language information or null
066     */
067    public final Locale getLocale() {
068        return locale;
069    }
070    
071    /**
072     * Get the track ID as defined by the media container format. The ID of each
073     * <code>Track</code> must be unique for its source {@link Media}.
074     * @return the <code>Track</code>s unique ID
075     */
076    public final long getTrackID() {
077        return trackID;
078    }
079    
080    /**
081     * @return a Map containing all known metadata for this <code>Track</code>
082     */
083    public final Map<String,Object> getMetadata() {
084        return metadata;
085    }
086    
087    Track(long trackID, Map<String,Object> metadata) {
088        this.trackID = trackID;
089        
090        Object value = metadata.get("name");
091        if (null != value && value instanceof String) {
092            name = (String)value;
093        }
094        
095        value = metadata.get("locale");
096        if (null != value && value instanceof Locale) {
097            locale = (Locale)value;
098        }
099        
100        this.metadata = Collections.unmodifiableMap(metadata);
101    }
102    
103    private String description;
104    @Override
105    public final String toString() {
106        synchronized(this) {
107            if (null == description) {
108                StringBuilder sb = new StringBuilder();
109                Map<String,Object> md = getMetadata();
110
111                sb.append(this.getClass().getName());
112                sb.append("[ track id = ");
113                sb.append(trackID);
114                
115                for (Map.Entry<String,Object> entry : md.entrySet()) {
116                    Object value = entry.getValue();
117                    if (null != value) {
118                        sb.append(", ");
119                        sb.append(entry.getKey());
120                        sb.append(" = ");
121                        sb.append(value.toString());
122                    }
123                }
124                sb.append("]");
125                description = sb.toString();
126            }
127        }
128        return description;
129    }
130}