Refactor artist and release in GoogleTrack as reference

extensions/data-transfer/portability-data-transfer-google/src/main/java/org/datatransferproject/datatransfer/google/music/GoogleMusicExporter.java

@@ -270,7 +270,7 @@ private int getTokenPrefixLength(String token) {
   private MusicPlaylistItem convertPlaylistItem(
       String playlistId, GooglePlaylistItem googlePlaylistItem) throws ParseException {
     GoogleTrack track = googlePlaylistItem.getTrack();
-    GoogleRelease release = track.getRelease();
+    GoogleRelease release = track.getReleaseReference();
     return new MusicPlaylistItem(
         new MusicRecording(
             track.getIsrc(),
@@ -280,7 +280,7 @@ private MusicPlaylistItem convertPlaylistItem(
                 release.getIcpn(),
                 release.getTitle(),
                 createMusicGroups(release.getArtists())),
-            createMusicGroups(track.getArtists()),
+            createMusicGroups(track.getArtistReferences()),
             "EXPLICIT_TYPE_EXPLICIT".equals(track.getExplicitType())),
         playlistId,
         googlePlaylistItem.getOrder());

extensions/data-transfer/portability-data-transfer-google/src/main/java/org/datatransferproject/datatransfer/google/music/GoogleMusicImporter.java

@@ -268,15 +268,15 @@ private ImportPlaylistItemRequest buildImportPlaylistItemRequest(
 
     googleTrack.setIsrc(playlistItem.getTrack().getIsrcCode());
     googleTrack.setTitle(playlistItem.getTrack().getTitle());
-    googleTrack.setArtists(getArtists(playlistItem.getTrack().getByArtists()));
+    googleTrack.setArtistReferences(getArtists(playlistItem.getTrack().getByArtists()));
     googleTrack.setDuration(
         Durations.toString(Durations.fromMillis(playlistItem.getTrack().getDurationMillis())));
     if (playlistItem.getTrack().getIsExplicit()) {
       googleTrack.setExplicitType("EXPLICIT_TYPE_EXPLICIT");
     } else {
       googleTrack.setExplicitType("EXPLICIT_TYPE_NOT_EXPLICIT");
     }
-    googleTrack.setRelease(googleRelease);
+    googleTrack.setReleaseReference(googleRelease);
 
     googlePlaylistItem.setTrack(googleTrack);
     googlePlaylistItem.setOrder(playlistItem.getOrder());

extensions/data-transfer/portability-data-transfer-google/src/main/java/org/datatransferproject/datatransfer/google/musicModels/GoogleTrack.java

@@ -30,14 +30,14 @@ public class GoogleTrack {
   @JsonProperty("isrc")
   private String isrc;
 
-  @JsonProperty("release")
-  private GoogleRelease release;
+  @JsonProperty("releaseReference")
+  private GoogleRelease releaseReference;
 
   @JsonProperty("title")
   private String title;
 
-  @JsonProperty("artists")
-  private GoogleArtist[] artists;
+  @JsonProperty("artistReferences")
+  private GoogleArtist[] artistReferences;
 
   // Json format of google.protobuf.Duration is encoded as a string ends in the suffix "s".
   // 3 seconds and 1 microsecond should be expressed in JSON format as "3.000001s".
@@ -51,16 +51,16 @@ public String getIsrc() {
     return isrc;
   }
 
-  public GoogleRelease getRelease() {
-    return release;
+  public GoogleRelease getReleaseReference() {
+    return releaseReference;
   }
 
   public String getTitle() {
     return title;
   }
 
-  public GoogleArtist[] getArtists() {
-    return artists;
+  public GoogleArtist[] getArtistReferences() {
+    return artistReferences;
   }
 
   public String getDuration() {
@@ -82,16 +82,16 @@ public void setIsrc(String isrc) {
     this.isrc = isrc;
   }
 
-  public void setRelease(GoogleRelease release) {
-    this.release = release;
+  public void setReleaseReference(GoogleRelease releaseReference) {
+    this.releaseReference = releaseReference;
   }
 
   public void setTitle(String title) {
     this.title = title;
   }
 
-  public void setArtists(GoogleArtist[] artists) {
-    this.artists = artists;
+  public void setArtistReferences(GoogleArtist[] artistReferences) {
+    this.artistReferences = artistReferences;
   }
 
   public void setDuration(String duration) {
@@ -112,9 +112,9 @@ public boolean equals(Object o) {
     }
     GoogleTrack that = (GoogleTrack) o;
     return Objects.equals(isrc, that.isrc)
-        && Objects.equals(release, that.release)
+        && Objects.equals(releaseReference, that.releaseReference)
         && Objects.equals(title, that.title)
-        && Arrays.equals(artists, that.artists)
+        && Arrays.equals(artistReferences, that.artistReferences)
         && Objects.equals(duration, that.duration)
         && Objects.equals(explicitType, that.explicitType);
   }
@@ -123,9 +123,9 @@ public boolean equals(Object o) {
   public int hashCode() {
     return Objects.hash(
         getIsrc(),
-        getRelease(),
+        getReleaseReference(),
         getTitle(),
-        Arrays.hashCode(getArtists()),
+        Arrays.hashCode(getArtistReferences()),
         getDuration(),
         getExplicitType());
   }

extensions/data-transfer/portability-data-transfer-google/src/test/java/org/datatransferproject/datatransfer/google/music/GoogleMusicExporterTest.java

@@ -250,7 +250,7 @@ private GooglePlaylistItem setUpSinglePlaylistItem(String isrc, String icpn) {
     GoogleRelease release = new GoogleRelease();
     release.setIcpn(icpn);
     track.setIsrc(isrc);
-    track.setRelease(release);
+    track.setReleaseReference(release);
     track.setExplicitType("EXPLICIT_TYPE_EXPLICIT");
     playlistItemEntry.setTrack(track);
     return playlistItemEntry;

extensions/data-transfer/portability-data-transfer-google/src/test/java/org/datatransferproject/datatransfer/google/music/GoogleMusicImporterTest.java

@@ -307,7 +307,7 @@ private GooglePlaylistItem buildGooglePlaylistItem(String trackIsrc, String rele
     GoogleTrack track = new GoogleTrack();
     track.setIsrc(trackIsrc);
     track.setDuration(Durations.toString(Durations.fromMillis(180000L)));
-    track.setRelease(release);
+    track.setReleaseReference(release);
     track.setExplicitType("EXPLICIT_TYPE_NOT_EXPLICIT"
         + "");