Add possibility to iterate over Commands

PiperOrigin-RevId: 364836973

library/common/src/main/java/com/google/android/exoplayer2/Player.java

@@ -690,6 +690,7 @@ public interface Player {
      *
      * @param index The index. Must be between 0 (inclusive) and {@link #size()} (exclusive).
      * @return The {@link EventFlags event} at the given index.
+     * @throws IndexOutOfBoundsException If index is outside the allowed range.
      */
     @EventFlags
     public int get(int index) {
@@ -787,6 +788,23 @@ public interface Player {
       return flags.contains(command);
     }
 
+    /** Returns the number of commands in this set. */
+    public int size() {
+      return flags.size();
+    }
+
+    /**
+     * Returns the {@link Command} at the given index.
+     *
+     * @param index The index. Must be between 0 (inclusive) and {@link #size()} (exclusive).
+     * @return The {@link Command} at the given index.
+     * @throws IndexOutOfBoundsException If index is outside the allowed range.
+     */
+    @Command
+    public int get(int index) {
+      return flags.get(index);
+    }
+
     @Override
     public boolean equals(@Nullable Object obj) {
       if (this == obj) {

library/common/src/main/java/com/google/android/exoplayer2/util/ExoFlags.java

@@ -15,6 +15,7 @@
  */
 package com.google.android.exoplayer2.util;
 
+import static com.google.android.exoplayer2.util.Assertions.checkIndex;
 import static com.google.android.exoplayer2.util.Assertions.checkState;
 
 import android.util.SparseBooleanArray;
@@ -152,10 +153,10 @@ public final class ExoFlags {
    *
    * @param index The index. Must be between 0 (inclusive) and {@link #size()} (exclusive).
    * @return The flag at the given index.
-   * @throws IllegalArgumentException If index is outside the allowed range.
+   * @throws IndexOutOfBoundsException If index is outside the allowed range.
    */
   public int get(int index) {
-    Assertions.checkArgument(index >= 0 && index < size());
+    checkIndex(index, /* start= */ 0, /* limit= */ size());
     return flags.keyAt(index);
   }
 

library/common/src/test/java/com/google/android/exoplayer2/util/ExoFlagsTest.java

@@ -122,17 +122,17 @@ public final class ExoFlagsTest {
   }
 
   @Test
-  public void get_withNegativeIndex_throwsIllegalArgumentException() {
+  public void get_withNegativeIndex_throwsIndexOutOfBoundsException() {
     ExoFlags flags = new ExoFlags.Builder().build();
 
-    assertThrows(IllegalArgumentException.class, () -> flags.get(/* index= */ -1));
+    assertThrows(IndexOutOfBoundsException.class, () -> flags.get(/* index= */ -1));
   }
 
   @Test
-  public void get_withIndexExceedingSize_throwsIllegalArgumentException() {
+  public void get_withIndexExceedingSize_throwsIndexOutOfBoundsException() {
     ExoFlags flags = new ExoFlags.Builder().add(/* flag= */ 0).add(/* flag= */ 123).build();
 
-    assertThrows(IllegalArgumentException.class, () -> flags.get(/* index= */ 2));
+    assertThrows(IndexOutOfBoundsException.class, () -> flags.get(/* index= */ 2));
   }
 
   @Test