Clean up RtpH265Reader

libraries/exoplayer_rtsp/src/main/java/androidx/media3/exoplayer/rtsp/RtspMediaTrack.java

@@ -44,10 +44,10 @@ import com.google.common.collect.ImmutableMap;
   // Format specific parameter names.
   private static final String PARAMETER_PROFILE_LEVEL_ID = "profile-level-id";
   private static final String PARAMETER_SPROP_PARAMS = "sprop-parameter-sets";
-  private static final String H265_SPS = "sprop-sps";
-  private static final String H265_PPS = "sprop-pps";
-  private static final String H265_VPS = "sprop-vps";
-  private static final String H265_MAX_DON_DIFF = "sprop-max-don-diff";
+  private static final String PARAMETER_SPROP_H265_SPS = "sprop-sps";
+  private static final String PARAMETER_SPROP_H265_PPS = "sprop-pps";
+  private static final String PARAMETER_SPROP_H265_VPS = "sprop-vps";
+  private static final String PARAMETER_SPROP_H265_MAX_DON_DIFF = "sprop-max-don-diff";
 
   /** Prefix for the RFC6381 codecs string for AAC formats. */
   private static final String AAC_CODECS_PREFIX = "mp4a.40.";
@@ -221,31 +221,30 @@ import com.google.common.collect.ImmutableMap;
 
   private static void processH265FmtpAttribute(
       Format.Builder formatBuilder, ImmutableMap<String, String> fmtpAttributes) {
-    if (fmtpAttributes.containsKey(H265_MAX_DON_DIFF)) {
-      checkArgument(Integer.parseInt(checkNotNull(fmtpAttributes.get(H265_MAX_DON_DIFF))) == 0);
+    if (fmtpAttributes.containsKey(PARAMETER_SPROP_H265_MAX_DON_DIFF)) {
+      checkArgument(
+          Integer.parseInt(checkNotNull(fmtpAttributes.get(PARAMETER_SPROP_H265_MAX_DON_DIFF)))
+              == 0,
+          "non-zero sprop-max-don-diff is not supported");
     }
 
-    checkArgument(fmtpAttributes.containsKey(H265_SPS));
-    String spropSPS = checkNotNull(fmtpAttributes.get(H265_SPS));
-    checkArgument(fmtpAttributes.containsKey(H265_PPS));
-    String spropPPS = checkNotNull(fmtpAttributes.get(H265_PPS));
-    checkArgument(fmtpAttributes.containsKey(H265_VPS));
-    String spropVPS = checkNotNull(fmtpAttributes.get(H265_VPS));
-    String[] parameterSets = new String[] {spropSPS, spropPPS, spropVPS};
+    checkArgument(fmtpAttributes.containsKey(PARAMETER_SPROP_H265_SPS));
+    String spropSPS = checkNotNull(fmtpAttributes.get(PARAMETER_SPROP_H265_SPS));
+    checkArgument(fmtpAttributes.containsKey(PARAMETER_SPROP_H265_PPS));
+    String spropPPS = checkNotNull(fmtpAttributes.get(PARAMETER_SPROP_H265_PPS));
+    checkArgument(fmtpAttributes.containsKey(PARAMETER_SPROP_H265_VPS));
+    String spropVPS = checkNotNull(fmtpAttributes.get(PARAMETER_SPROP_H265_VPS));
 
-    checkArgument(parameterSets.length == 3);
-    ImmutableList<byte[]> initializationData =
-        ImmutableList.of(
-            getInitializationDataFromParameterSet(parameterSets[0]),
-            getInitializationDataFromParameterSet(parameterSets[1]),
-            getInitializationDataFromParameterSet(parameterSets[2]));
+    byte[] vpsNalData = getInitializationDataFromParameterSet(spropVPS);
+    byte[] spsNalData = getInitializationDataFromParameterSet(spropSPS);
+    byte[] ppsNalData = getInitializationDataFromParameterSet(spropPPS);
+    ImmutableList<byte[]> initializationData = ImmutableList.of(vpsNalData, spsNalData, ppsNalData);
     formatBuilder.setInitializationData(initializationData);
 
     // Process SPS (Sequence Parameter Set).
-    byte[] spsNalDataWithStartCode = initializationData.get(0);
     NalUnitUtil.H265SpsData spsData =
         NalUnitUtil.parseH265SpsNalUnit(
-            spsNalDataWithStartCode, NAL_START_CODE.length, spsNalDataWithStartCode.length);
+            spsNalData, NAL_START_CODE.length, spsNalData.length);
     formatBuilder.setPixelWidthHeightRatio(spsData.pixelWidthHeightRatio);
     formatBuilder.setHeight(spsData.height);
     formatBuilder.setWidth(spsData.width);