diff --git a/libraries/exoplayer_dash/src/test/java/androidx/media3/exoplayer/dash/offline/DashDownloadTestData.java b/libraries/exoplayer_dash/src/test/java/androidx/media3/exoplayer/dash/offline/DashDownloadTestData.java
index 03a18c1739..a42da8d2ab 100644
--- a/libraries/exoplayer_dash/src/test/java/androidx/media3/exoplayer/dash/offline/DashDownloadTestData.java
+++ b/libraries/exoplayer_dash/src/test/java/androidx/media3/exoplayer/dash/offline/DashDownloadTestData.java
@@ -19,12 +19,12 @@ import android.net.Uri;
 import java.nio.charset.StandardCharsets;
 
 /** Data for DASH downloading tests. */
-/* package */ interface DashDownloadTestData {
+/* package */ final class DashDownloadTestData {
 
-  String TEST_ID = "test.mpd";
-  Uri TEST_MPD_URI = Uri.parse(TEST_ID);
+  public static final String TEST_ID = "test.mpd";
+  public static final Uri TEST_MPD_URI = Uri.parse(TEST_ID);
 
-  byte[] TEST_MPD =
+  public static final byte[] TEST_MPD =
       ("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
               + "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" type=\"static\" "
               + "    mediaPresentationDuration=\"PT31S\">\n"
@@ -88,7 +88,7 @@ import java.nio.charset.StandardCharsets;
               + "</MPD>")
           .getBytes(StandardCharsets.UTF_8);
 
-  byte[] TEST_MPD_NO_INDEX =
+  public static final byte[] TEST_MPD_NO_INDEX =
       ("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
               + "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" type=\"dynamic\">\n"
               + "    <Period start=\"PT6462826.784S\" >\n"
@@ -100,4 +100,6 @@ import java.nio.charset.StandardCharsets;
               + "    </Period>\n"
               + "</MPD>")
           .getBytes(StandardCharsets.UTF_8);
+
+  private DashDownloadTestData() {}
 }
diff --git a/libraries/exoplayer_hls/src/test/java/androidx/media3/exoplayer/hls/offline/HlsDownloadTestData.java b/libraries/exoplayer_hls/src/test/java/androidx/media3/exoplayer/hls/offline/HlsDownloadTestData.java
index 909fb1faa1..8c308ad261 100644
--- a/libraries/exoplayer_hls/src/test/java/androidx/media3/exoplayer/hls/offline/HlsDownloadTestData.java
+++ b/libraries/exoplayer_hls/src/test/java/androidx/media3/exoplayer/hls/offline/HlsDownloadTestData.java
@@ -18,24 +18,24 @@ package androidx.media3.exoplayer.hls.offline;
 import java.nio.charset.StandardCharsets;
 
 /** Data for HLS downloading tests. */
-/* package */ interface HlsDownloadTestData {
+/* package */ final class HlsDownloadTestData {
 
-  String MULTIVARIANT_PLAYLIST_URI = "test.m3u8";
-  int MULTIVARIANT_MEDIA_PLAYLIST_1_INDEX = 0;
-  int MULTIVARIANT_MEDIA_PLAYLIST_2_INDEX = 1;
-  int MULTIVARIANT_MEDIA_PLAYLIST_3_INDEX = 2;
-  int MULTIVARIANT_MEDIA_PLAYLIST_0_INDEX = 3;
+  public static final String MULTIVARIANT_PLAYLIST_URI = "test.m3u8";
+  public static final int MULTIVARIANT_MEDIA_PLAYLIST_1_INDEX = 0;
+  public static final int MULTIVARIANT_MEDIA_PLAYLIST_2_INDEX = 1;
+  public static final int MULTIVARIANT_MEDIA_PLAYLIST_3_INDEX = 2;
+  public static final int MULTIVARIANT_MEDIA_PLAYLIST_0_INDEX = 3;
 
-  String MEDIA_PLAYLIST_0_DIR = "gear0/";
-  String MEDIA_PLAYLIST_0_URI = MEDIA_PLAYLIST_0_DIR + "prog_index.m3u8";
-  String MEDIA_PLAYLIST_1_DIR = "gear1/";
-  String MEDIA_PLAYLIST_1_URI = MEDIA_PLAYLIST_1_DIR + "prog_index.m3u8";
-  String MEDIA_PLAYLIST_2_DIR = "gear2/";
-  String MEDIA_PLAYLIST_2_URI = MEDIA_PLAYLIST_2_DIR + "prog_index.m3u8";
-  String MEDIA_PLAYLIST_3_DIR = "gear3/";
-  String MEDIA_PLAYLIST_3_URI = MEDIA_PLAYLIST_3_DIR + "prog_index.m3u8";
+  public static final String MEDIA_PLAYLIST_0_DIR = "gear0/";
+  public static final String MEDIA_PLAYLIST_0_URI = MEDIA_PLAYLIST_0_DIR + "prog_index.m3u8";
+  public static final String MEDIA_PLAYLIST_1_DIR = "gear1/";
+  public static final String MEDIA_PLAYLIST_1_URI = MEDIA_PLAYLIST_1_DIR + "prog_index.m3u8";
+  public static final String MEDIA_PLAYLIST_2_DIR = "gear2/";
+  public static final String MEDIA_PLAYLIST_2_URI = MEDIA_PLAYLIST_2_DIR + "prog_index.m3u8";
+  public static final String MEDIA_PLAYLIST_3_DIR = "gear3/";
+  public static final String MEDIA_PLAYLIST_3_URI = MEDIA_PLAYLIST_3_DIR + "prog_index.m3u8";
 
-  byte[] MULTIVARIANT_PLAYLIST_DATA =
+  public static final byte[] MULTIVARIANT_PLAYLIST_DATA =
       ("#EXTM3U\n"
               + "#EXT-X-STREAM-INF:BANDWIDTH=232370,CODECS=\"mp4a.40.2, avc1.4d4015\"\n"
               + MEDIA_PLAYLIST_1_URI
@@ -50,7 +50,7 @@ import java.nio.charset.StandardCharsets;
               + MEDIA_PLAYLIST_0_URI)
           .getBytes(StandardCharsets.UTF_8);
 
-  byte[] MEDIA_PLAYLIST_DATA =
+  public static final byte[] MEDIA_PLAYLIST_DATA =
       ("#EXTM3U\n"
               + "#EXT-X-TARGETDURATION:10\n"
               + "#EXT-X-VERSION:3\n"
@@ -65,9 +65,9 @@ import java.nio.charset.StandardCharsets;
               + "#EXT-X-ENDLIST")
           .getBytes(StandardCharsets.UTF_8);
 
-  String ENC_MEDIA_PLAYLIST_URI = "enc_index.m3u8";
+  public static final String ENC_MEDIA_PLAYLIST_URI = "enc_index.m3u8";
 
-  byte[] ENC_MEDIA_PLAYLIST_DATA =
+  public static final byte[] ENC_MEDIA_PLAYLIST_DATA =
       ("#EXTM3U\n"
               + "#EXT-X-TARGETDURATION:10\n"
               + "#EXT-X-VERSION:3\n"
@@ -83,4 +83,6 @@ import java.nio.charset.StandardCharsets;
               + "fileSequence2.ts\n"
               + "#EXT-X-ENDLIST")
           .getBytes(StandardCharsets.UTF_8);
+
+  private HlsDownloadTestData() {}
 }