Stop using Map<Integer, X>

Lint recommends switching to SparseArray<X> instead.
This is done for the DASH case. For the Cast case it's
easier to use a switch statement.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184119312

extensions/cast/src/main/java/com/google/android/exoplayer2/ext/cast/CastUtils.java

@@ -20,17 +20,12 @@ import com.google.android.exoplayer2.Format;
 import com.google.android.gms.cast.CastStatusCodes;
 import com.google.android.gms.cast.MediaInfo;
 import com.google.android.gms.cast.MediaTrack;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 
 /**
  * Utility methods for ExoPlayer/Cast integration.
  */
 /* package */ final class CastUtils {
 
-  private static final Map<Integer, String> CAST_STATUS_CODE_TO_STRING;
-
   /**
    * Returns the duration in microseconds advertised by a media info, or {@link C#TIME_UNSET} if
    * unknown or not applicable.
@@ -53,8 +48,49 @@ import java.util.Map;
    *     {@link CastStatusCodes}.
    */
   public static String getLogString(int statusCode) {
-    String description = CAST_STATUS_CODE_TO_STRING.get(statusCode);
-    return description != null ? description : "Unknown.";
+    switch (statusCode) {
+      case CastStatusCodes.APPLICATION_NOT_FOUND:
+        return "A requested application could not be found.";
+      case CastStatusCodes.APPLICATION_NOT_RUNNING:
+        return "A requested application is not currently running.";
+      case CastStatusCodes.AUTHENTICATION_FAILED:
+        return "Authentication failure.";
+      case CastStatusCodes.CANCELED:
+        return "An in-progress request has been canceled, most likely because another action has "
+            + "preempted it.";
+      case CastStatusCodes.ERROR_SERVICE_CREATION_FAILED:
+        return "The Cast Remote Display service could not be created.";
+      case CastStatusCodes.ERROR_SERVICE_DISCONNECTED:
+        return "The Cast Remote Display service was disconnected.";
+      case CastStatusCodes.FAILED:
+        return "The in-progress request failed.";
+      case CastStatusCodes.INTERNAL_ERROR:
+        return "An internal error has occurred.";
+      case CastStatusCodes.INTERRUPTED:
+        return "A blocking call was interrupted while waiting and did not run to completion.";
+      case CastStatusCodes.INVALID_REQUEST:
+        return "An invalid request was made.";
+      case CastStatusCodes.MESSAGE_SEND_BUFFER_TOO_FULL:
+        return "A message could not be sent because there is not enough room in the send buffer at "
+            + "this time.";
+      case CastStatusCodes.MESSAGE_TOO_LARGE:
+        return "A message could not be sent because it is too large.";
+      case CastStatusCodes.NETWORK_ERROR:
+        return "Network I/O error.";
+      case CastStatusCodes.NOT_ALLOWED:
+        return "The request was disallowed and could not be completed.";
+      case CastStatusCodes.REPLACED:
+        return "The request's progress is no longer being tracked because another request of the "
+            + "same type has been made before the first request completed.";
+      case CastStatusCodes.SUCCESS:
+        return "Success.";
+      case CastStatusCodes.TIMEOUT:
+        return "An operation has timed out.";
+      case CastStatusCodes.UNKNOWN_ERROR:
+        return "An unknown, unexpected error has occurred.";
+      default:
+        return "Unknown: " + statusCode;
+    }
   }
 
   /**
@@ -69,41 +105,6 @@ import java.util.Map;
         null, null, Format.NO_VALUE, 0, mediaTrack.getLanguage());
   }
 
-  static {
-    HashMap<Integer, String> statusCodeToString = new HashMap<>();
-    statusCodeToString.put(CastStatusCodes.APPLICATION_NOT_FOUND,
-        "A requested application could not be found.");
-    statusCodeToString.put(CastStatusCodes.APPLICATION_NOT_RUNNING,
-        "A requested application is not currently running.");
-    statusCodeToString.put(CastStatusCodes.AUTHENTICATION_FAILED, "Authentication failure.");
-    statusCodeToString.put(CastStatusCodes.CANCELED, "An in-progress request has been "
-        + "canceled, most likely because another action has preempted it.");
-    statusCodeToString.put(CastStatusCodes.ERROR_SERVICE_CREATION_FAILED,
-        "The Cast Remote Display service could not be created.");
-    statusCodeToString.put(CastStatusCodes.ERROR_SERVICE_DISCONNECTED,
-        "The Cast Remote Display service was disconnected.");
-    statusCodeToString.put(CastStatusCodes.FAILED, "The in-progress request failed.");
-    statusCodeToString.put(CastStatusCodes.INTERNAL_ERROR, "An internal error has occurred.");
-    statusCodeToString.put(CastStatusCodes.INTERRUPTED,
-        "A blocking call was interrupted while waiting and did not run to completion.");
-    statusCodeToString.put(CastStatusCodes.INVALID_REQUEST, "An invalid request was made.");
-    statusCodeToString.put(CastStatusCodes.MESSAGE_SEND_BUFFER_TOO_FULL, "A message could "
-        + "not be sent because there is not enough room in the send buffer at this time.");
-    statusCodeToString.put(CastStatusCodes.MESSAGE_TOO_LARGE,
-        "A message could not be sent because it is too large.");
-    statusCodeToString.put(CastStatusCodes.NETWORK_ERROR, "Network I/O error.");
-    statusCodeToString.put(CastStatusCodes.NOT_ALLOWED,
-        "The request was disallowed and could not be completed.");
-    statusCodeToString.put(CastStatusCodes.REPLACED,
-        "The request's progress is no longer being tracked because another request of the same type"
-            + " has been made before the first request completed.");
-    statusCodeToString.put(CastStatusCodes.SUCCESS, "Success.");
-    statusCodeToString.put(CastStatusCodes.TIMEOUT, "An operation has timed out.");
-    statusCodeToString.put(CastStatusCodes.UNKNOWN_ERROR,
-        "An unknown, unexpected error has occurred.");
-    CAST_STATUS_CODE_TO_STRING = Collections.unmodifiableMap(statusCodeToString);
-  }
-
   private CastUtils() {}
 
 }

library/dash/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaPeriod.java

@@ -17,6 +17,7 @@ package com.google.android.exoplayer2.source.dash;
 
 import android.support.annotation.IntDef;
 import android.util.Pair;
+import android.util.SparseArray;
 import android.util.SparseIntArray;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
@@ -48,10 +49,8 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.HashMap;
 import java.util.IdentityHashMap;
 import java.util.List;
-import java.util.Map;
 
 /** A DASH {@link MediaPeriod}. */
 /* package */ final class DashMediaPeriod
@@ -182,7 +181,7 @@ import java.util.Map;
   @Override
   public long selectTracks(TrackSelection[] selections, boolean[] mayRetainStreamFlags,
       SampleStream[] streams, boolean[] streamResetFlags, long positionUs) {
-    Map<Integer, ChunkSampleStream<DashChunkSource>> primarySampleStreams = new HashMap<>();
+    SparseArray<ChunkSampleStream<DashChunkSource>> primarySampleStreams = new SparseArray<>();
     List<EventSampleStream> eventSampleStreamList = new ArrayList<>();
 
     selectPrimarySampleStreams(selections, mayRetainStreamFlags, streams, streamResetFlags,
@@ -193,7 +192,9 @@ import java.util.Map;
         positionUs, primarySampleStreams);
 
     sampleStreams = newSampleStreamArray(primarySampleStreams.size());
-    primarySampleStreams.values().toArray(sampleStreams);
+    for (int i = 0; i < sampleStreams.length; i++) {
+      sampleStreams[i] = primarySampleStreams.valueAt(i);
+    }
     eventSampleStreams = new EventSampleStream[eventSampleStreamList.size()];
     eventSampleStreamList.toArray(eventSampleStreams);
     compositeSequenceableLoader =
@@ -201,9 +202,13 @@ import java.util.Map;
     return positionUs;
   }
 
-  private void selectPrimarySampleStreams(TrackSelection[] selections,
-      boolean[] mayRetainStreamFlags, SampleStream[] streams, boolean[] streamResetFlags,
-      long positionUs, Map<Integer, ChunkSampleStream<DashChunkSource>> primarySampleStreams) {
+  private void selectPrimarySampleStreams(
+      TrackSelection[] selections,
+      boolean[] mayRetainStreamFlags,
+      SampleStream[] streams,
+      boolean[] streamResetFlags,
+      long positionUs,
+      SparseArray<ChunkSampleStream<DashChunkSource>> primarySampleStreams) {
     for (int i = 0; i < selections.length; i++) {
       if (streams[i] instanceof ChunkSampleStream) {
         @SuppressWarnings("unchecked")
@@ -259,9 +264,13 @@ import java.util.Map;
     }
   }
 
-  private void selectEmbeddedSampleStreams(TrackSelection[] selections,
-      boolean[] mayRetainStreamFlags, SampleStream[] streams, boolean[] streamResetFlags,
-      long positionUs, Map<Integer, ChunkSampleStream<DashChunkSource>> primarySampleStreams) {
+  private void selectEmbeddedSampleStreams(
+      TrackSelection[] selections,
+      boolean[] mayRetainStreamFlags,
+      SampleStream[] streams,
+      boolean[] streamResetFlags,
+      long positionUs,
+      SparseArray<ChunkSampleStream<DashChunkSource>> primarySampleStreams) {
     for (int i = 0; i < selections.length; i++) {
       if ((streams[i] instanceof EmbeddedSampleStream || streams[i] instanceof EmptySampleStream)
           && (selections[i] == null || !mayRetainStreamFlags[i])) {