Implement database CachedContentIndex.Storage

PiperOrigin-RevId: 231600104

library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/SimpleCache.java

@@ -408,8 +408,8 @@ public final class SimpleCache implements Cache {
       if (isRootDirectory && fileName.indexOf('.') == -1) {
         loadDirectory(file, /* isRootDirectory= */ false);
       } else {
-        if (isRootDirectory && CachedContentIndex.FILE_NAME.equals(fileName)) {
-          // Skip the (expected) index file in the root directory.
+        if (isRootDirectory && CachedContentIndex.isIndexFile(fileName)) {
+          // Skip the (expected) index files in the root directory.
           continue;
         }
         long fileLength = file.length();

library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CachedContentIndexTest.java

@@ -151,7 +151,8 @@ public class CachedContentIndexTest {
 
   @Test
   public void testLoadV1() throws Exception {
-    FileOutputStream fos = new FileOutputStream(new File(cacheDir, CachedContentIndex.FILE_NAME));
+    FileOutputStream fos =
+        new FileOutputStream(new File(cacheDir, CachedContentIndex.FILE_NAME_ATOMIC));
     fos.write(testIndexV1File);
     fos.close();
 
@@ -169,7 +170,8 @@ public class CachedContentIndexTest {
 
   @Test
   public void testLoadV2() throws Exception {
-    FileOutputStream fos = new FileOutputStream(new File(cacheDir, CachedContentIndex.FILE_NAME));
+    FileOutputStream fos =
+        new FileOutputStream(new File(cacheDir, CachedContentIndex.FILE_NAME_ATOMIC));
     fos.write(testIndexV2File);
     fos.close();
 
@@ -220,7 +222,7 @@ public class CachedContentIndexTest {
         new CachedContentIndex(cacheDir, key), new CachedContentIndex(cacheDir, key));
 
     // Rename the index file from the test above
-    File file1 = new File(cacheDir, CachedContentIndex.FILE_NAME);
+    File file1 = new File(cacheDir, CachedContentIndex.FILE_NAME_ATOMIC);
     File file2 = new File(cacheDir, "file2compare");
     assertThat(file1.renameTo(file2)).isTrue();