Changes for SQLite databases on internal storage

- Remove ability to encrypt content index for SQLite storage
- Remove hack for specifying arbitrary database location

PiperOrigin-RevId: 232863763

library/core/src/main/java/com/google/android/exoplayer2/database/ExoDatabaseProvider.java

@@ -16,20 +16,16 @@
 package com.google.android.exoplayer2.database;
 
 import android.content.Context;
-import android.content.ContextWrapper;
 import android.database.Cursor;
-import android.database.DatabaseErrorHandler;
 import android.database.SQLException;
 import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteOpenHelper;
-import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.util.Log;
-import java.io.File;
 
 /**
  * An {@link SQLiteOpenHelper} that provides instances of a standalone ExoPlayer database.
  *
- * <p>Suitable for use by applications that do not already have their own database, or which would
+ * <p>Suitable for use by applications that do not already have their own database, or that would
  * prefer to keep ExoPlayer tables isolated in their own database. Other applications should prefer
  * to use {@link DefaultDatabaseProvider} with their own {@link SQLiteOpenHelper}.
  */
@@ -51,15 +47,6 @@ public final class ExoDatabaseProvider extends SQLiteOpenHelper implements Datab
     super(context.getApplicationContext(), DATABASE_NAME, /* factory= */ null, VERSION);
   }
 
-  /**
-   * Provides instances of the database located at the specified file.
-   *
-   * @param file The database file.
-   */
-  public ExoDatabaseProvider(File file) {
-    super(new DatabaseFileProvidingContext(file), file.getName(), /* factory= */ null, VERSION);
-  }
-
   @Override
   public void onCreate(SQLiteDatabase db) {
     // Features create their own tables.
@@ -105,48 +92,4 @@ public final class ExoDatabaseProvider extends SQLiteOpenHelper implements Datab
       }
     }
   }
-
-  // TODO: This is fragile. Stop using it if/when SQLiteOpenHelper can be instantiated without a
-  // context [Internal ref: b/123351819], or by injecting a Context into all components that need
-  // to instantiate an ExoDatabaseProvider.
-  /** A {@link Context} that implements methods called by {@link SQLiteOpenHelper}. */
-  private static class DatabaseFileProvidingContext extends ContextWrapper {
-
-    private final File file;
-
-    @SuppressWarnings("nullness:argument.type.incompatible")
-    public DatabaseFileProvidingContext(File file) {
-      super(/* base= */ null);
-      this.file = file;
-    }
-
-    @Override
-    public File getDatabasePath(String name) {
-      return file;
-    }
-
-    @Override
-    public SQLiteDatabase openOrCreateDatabase(
-        String name, int mode, SQLiteDatabase.CursorFactory factory) {
-      return openOrCreateDatabase(name, mode, factory, /* errorHandler= */ null);
-    }
-
-    @Override
-    @SuppressWarnings("nullness:argument.type.incompatible")
-    public SQLiteDatabase openOrCreateDatabase(
-        String name,
-        int mode,
-        SQLiteDatabase.CursorFactory factory,
-        @Nullable DatabaseErrorHandler errorHandler) {
-      File databasePath = getDatabasePath(name);
-      int flags = SQLiteDatabase.CREATE_IF_NECESSARY;
-      if ((mode & MODE_ENABLE_WRITE_AHEAD_LOGGING) != 0) {
-        flags |= SQLiteDatabase.ENABLE_WRITE_AHEAD_LOGGING;
-      }
-      if ((mode & MODE_NO_LOCALIZED_COLLATORS) != 0) {
-        flags |= SQLiteDatabase.NO_LOCALIZED_COLLATORS;
-      }
-      return SQLiteDatabase.openDatabase(databasePath.getPath(), factory, flags, errorHandler);
-    }
-  }
 }

library/core/src/main/java/com/google/android/exoplayer2/database/VersionTable.java

@@ -45,6 +45,8 @@ public final class VersionTable {
   private static final String COLUMN_FEATURE = "feature";
   private static final String COLUMN_VERSION = "version";
 
+  private static final String WHERE_FEATURE_EQUALS = COLUMN_FEATURE + " = ?";
+
   private static final String SQL_CREATE_TABLE_IF_NOT_EXISTS =
       "CREATE TABLE IF NOT EXISTS "
           + TABLE_NAME
@@ -62,7 +64,7 @@ public final class VersionTable {
   private VersionTable() {}
 
   /**
-   * Sets the version of tables belonging to the specified feature.
+   * Sets the version of the specified feature.
    *
    * @param writableDatabase The database to update.
    * @param feature The feature.
@@ -78,8 +80,21 @@ public final class VersionTable {
   }
 
   /**
-   * Returns the version of tables belonging to the specified feature, or {@link #VERSION_UNSET} if
-   * no version information is available.
+   * Removes the version of the specified feature.
+   *
+   * @param writableDatabase The database to update.
+   * @param feature The feature.
+   */
+  public static void removeVersion(SQLiteDatabase writableDatabase, @Feature int feature) {
+    if (!tableExists(writableDatabase, TABLE_NAME)) {
+      return;
+    }
+    writableDatabase.delete(TABLE_NAME, WHERE_FEATURE_EQUALS, featureArgument(feature));
+  }
+
+  /**
+   * Returns the version of the specified feature, or {@link #VERSION_UNSET} if no version
+   * information is available.
    *
    * @param database The database to query.
    * @param feature The feature.
@@ -88,14 +103,12 @@ public final class VersionTable {
     if (!tableExists(database, TABLE_NAME)) {
       return VERSION_UNSET;
     }
-    String selection = COLUMN_FEATURE + " = ?";
-    String[] selectionArgs = {Integer.toString(feature)};
     try (Cursor cursor =
         database.query(
             TABLE_NAME,
             new String[] {COLUMN_VERSION},
-            selection,
-            selectionArgs,
+            WHERE_FEATURE_EQUALS,
+            featureArgument(feature),
             /* groupBy= */ null,
             /* having= */ null,
             /* orderBy= */ null)) {
@@ -114,4 +127,8 @@ public final class VersionTable {
             readableDatabase, "sqlite_master", "tbl_name = ?", new String[] {tableName});
     return count > 0;
   }
+
+  private static String[] featureArgument(int feature) {
+    return new String[] {Integer.toString(feature)};
+  }
 }

library/core/src/main/java/com/google/android/exoplayer2/offline/DefaultDownloadIndex.java

@@ -73,7 +73,7 @@ public final class DefaultDownloadIndex implements DownloadIndex {
   private static final int COLUMN_INDEX_STREAM_KEYS = 14;
   private static final int COLUMN_INDEX_CUSTOM_METADATA = 15;
 
-  private static final String COLUMN_SELECTION_ID = COLUMN_ID + " = ?";
+  private static final String WHERE_ID_EQUALS = COLUMN_ID + " = ?";
 
   private static final String[] COLUMNS =
       new String[] {
@@ -152,7 +152,7 @@ public final class DefaultDownloadIndex implements DownloadIndex {
   @Nullable
   public DownloadState getDownloadState(String id) {
     ensureInitialized();
-    try (Cursor cursor = getCursor(COLUMN_SELECTION_ID, new String[] {id})) {
+    try (Cursor cursor = getCursor(WHERE_ID_EQUALS, new String[] {id})) {
       if (cursor.getCount() == 0) {
         return null;
       }
@@ -210,9 +210,7 @@ public final class DefaultDownloadIndex implements DownloadIndex {
   @Override
   public void removeDownloadState(String id) {
     ensureInitialized();
-    databaseProvider
-        .getWritableDatabase()
-        .delete(TABLE_NAME, COLUMN_SELECTION_ID, new String[] {id});
+    databaseProvider.getWritableDatabase().delete(TABLE_NAME, WHERE_ID_EQUALS, new String[] {id});
   }
 
   private void ensureInitialized() {

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

@@ -171,7 +171,6 @@ public final class SimpleCache implements Cache {
     } catch (CacheException e) {
       Log.e(TAG, "Storing index file failed", e);
     } finally {
-      contentIndex.release();
       unlockFolder(cacheDir);
       released = true;
     }

library/core/src/test/java/com/google/android/exoplayer2/database/VersionTableTest.java

@@ -68,6 +68,16 @@ public class VersionTableTest {
   }
 
   @Test
+  public void removeVersion_removesSetVersion() {
+    VersionTable.setVersion(writableDatabase, FEATURE_OFFLINE, 1);
+    assertThat(VersionTable.getVersion(readableDatabase, FEATURE_OFFLINE)).isEqualTo(1);
+
+    VersionTable.removeVersion(writableDatabase, FEATURE_OFFLINE);
+    assertThat(VersionTable.getVersion(readableDatabase, FEATURE_OFFLINE))
+        .isEqualTo(VersionTable.VERSION_UNSET);
+  }
+
+  @Test
   public void doesTableExist_nonExistingTable_returnsFalse() {
     assertThat(VersionTable.tableExists(readableDatabase, "NonExistingTable")).isFalse();
   }