Split MtpDatabase class into three classes. (18d70d5b) · Commits · e / os / android_frameworks_base

packages/MtpDocumentsProvider/src/com/android/mtp/MtpDatabase.java

+20 −462

Original line number	Diff line number	Diff line
		@@ -16,14 +16,12 @@

		package com.android.mtp;

		import static com.android.mtp.MtpDatabaseConstants.*;

		import android.content.ContentValues;
		import android.content.Context;
		import android.content.res.Resources;
		import android.database.Cursor;
		import android.database.DatabaseUtils;
		import android.database.sqlite.SQLiteDatabase;
		import android.database.sqlite.SQLiteOpenHelper;
		import android.database.sqlite.SQLiteQueryBuilder;
		import android.mtp.MtpObjectInfo;
		import android.provider.DocumentsContract.Document;
		import android.provider.DocumentsContract.Root;
		@@ -32,7 +30,6 @@ import com.android.internal.annotations.VisibleForTesting;

		import java.util.HashMap;
		import java.util.Map;
		import java.util.Objects;

		/**
		* Database for MTP objects.
		@@ -73,190 +70,27 @@ import java.util.Objects;
		*/
		@VisibleForTesting
		class MtpDatabase {
		private static final int VERSION = 1;
		private static final String NAME = "mtp";

		/**
		* Table representing documents including root documents.
		*/
		private static final String TABLE_DOCUMENTS = "Documents";

		/**
		* Table containing additional information only available for root documents.
		* The table uses same primary keys with corresponding documents.
		*/
		private static final String TABLE_ROOT_EXTRA = "RootExtra";

		/**
		* View to join Documents and RootExtra tables to provide roots information.
		*/
		private static final String VIEW_ROOTS = "Roots";

		static final String COLUMN_DEVICE_ID = "device_id";
		static final String COLUMN_STORAGE_ID = "storage_id";
		static final String COLUMN_OBJECT_HANDLE = "object_handle";
		static final String COLUMN_PARENT_DOCUMENT_ID = "parent_document_id";
		static final String COLUMN_ROW_STATE = "row_state";

		/**
		* The state represents that the row has a valid object handle.
		*/
		static final int ROW_STATE_VALID = 0;

		/**
		* The state represents that the rows added at the previous cycle and need to be updated with
		* fresh values.
		* The row may not have valid object handle. External application can still fetch the documents.
		* If the external application tries to fetch object handle, the provider resolves pending
		* documents with invalidated documents ahead.
		*/
		static final int ROW_STATE_INVALIDATED = 1;

		/**
		* The state represents the raw has a valid object handle but it may be going to be mapped with
		* another rows invalidated. After fetching all documents under the parent, the database tries
		* to map the pending documents and the invalidated documents in order to keep old document ID
		* alive.
		*/
		static final int ROW_STATE_PENDING = 2;

		/**
		* Mapping mode that uses MTP identifier to find corresponding rows.
		*/
		static final int MAP_BY_MTP_IDENTIFIER = 0;

		/**
		* Mapping mode that uses name to find corresponding rows.
		*/
		static final int MAP_BY_NAME = 1;

		private static final String SELECTION_DOCUMENT_ID = Document.COLUMN_DOCUMENT_ID + " = ?";
		private static final String SELECTION_ROOT_ID = Root.COLUMN_ROOT_ID + " = ?";
		private static final String SELECTION_ROOT_DOCUMENTS =
		COLUMN_DEVICE_ID + " = ? AND " + COLUMN_PARENT_DOCUMENT_ID + " IS NULL";
		private static final String SELECTION_CHILD_DOCUMENTS = COLUMN_PARENT_DOCUMENT_ID + " = ?";

		static class ParentNotFoundException extends Exception {}

		private static class OpenHelper extends SQLiteOpenHelper {
		private static final String QUERY_CREATE_DOCUMENTS =
		"CREATE TABLE " + TABLE_DOCUMENTS + " (" +
		Document.COLUMN_DOCUMENT_ID +
		" INTEGER PRIMARY KEY AUTOINCREMENT," +
		COLUMN_DEVICE_ID + " INTEGER NOT NULL," +
		COLUMN_STORAGE_ID + " INTEGER," +
		COLUMN_OBJECT_HANDLE + " INTEGER," +
		COLUMN_PARENT_DOCUMENT_ID + " INTEGER," +
		COLUMN_ROW_STATE + " INTEGER NOT NULL," +
		Document.COLUMN_MIME_TYPE + " TEXT," +
		Document.COLUMN_DISPLAY_NAME + " TEXT NOT NULL," +
		Document.COLUMN_SUMMARY + " TEXT," +
		Document.COLUMN_LAST_MODIFIED + " INTEGER," +
		Document.COLUMN_ICON + " INTEGER," +
		Document.COLUMN_FLAGS + " INTEGER NOT NULL," +
		Document.COLUMN_SIZE + " INTEGER NOT NULL);";

		private static final String QUERY_CREATE_ROOT_EXTRA =
		"CREATE TABLE " + TABLE_ROOT_EXTRA + " (" +
		Root.COLUMN_ROOT_ID + " INTEGER PRIMARY KEY," +
		Root.COLUMN_FLAGS + " INTEGER NOT NULL," +
		Root.COLUMN_AVAILABLE_BYTES + " INTEGER NOT NULL," +
		Root.COLUMN_CAPACITY_BYTES + " INTEGER NOT NULL," +
		Root.COLUMN_MIME_TYPES + " TEXT NOT NULL);";

		/**
		* Creates a view to join Documents table and RootExtra table on their primary keys to
		* provide DocumentContract.Root equivalent information.
		*/
		private static final String QUERY_CREATE_VIEW_ROOTS =
		"CREATE VIEW " + VIEW_ROOTS + " AS SELECT " +
		TABLE_DOCUMENTS + "." + Document.COLUMN_DOCUMENT_ID + " AS " +
		Root.COLUMN_ROOT_ID + "," +
		TABLE_ROOT_EXTRA + "." + Root.COLUMN_FLAGS + "," +
		TABLE_DOCUMENTS + "." + Document.COLUMN_ICON + " AS " +
		Root.COLUMN_ICON + "," +
		TABLE_DOCUMENTS + "." + Document.COLUMN_DISPLAY_NAME + " AS " +
		Root.COLUMN_TITLE + "," +
		TABLE_DOCUMENTS + "." + Document.COLUMN_SUMMARY + " AS " +
		Root.COLUMN_SUMMARY + "," +
		TABLE_DOCUMENTS + "." + Document.COLUMN_DOCUMENT_ID + " AS " +
		Root.COLUMN_DOCUMENT_ID + "," +
		TABLE_ROOT_EXTRA + "." + Root.COLUMN_AVAILABLE_BYTES + "," +
		TABLE_ROOT_EXTRA + "." + Root.COLUMN_CAPACITY_BYTES + "," +
		TABLE_ROOT_EXTRA + "." + Root.COLUMN_MIME_TYPES + "," +
		TABLE_DOCUMENTS + "." + COLUMN_ROW_STATE +
		" FROM " + TABLE_DOCUMENTS + " INNER JOIN " + TABLE_ROOT_EXTRA +
		" ON " +
		COLUMN_PARENT_DOCUMENT_ID + " IS NULL AND " +
		TABLE_DOCUMENTS + "." + Document.COLUMN_DOCUMENT_ID +
		"=" +
		TABLE_ROOT_EXTRA + "." + Root.COLUMN_ROOT_ID;

		public OpenHelper(Context context) {
		super(context, NAME, null, VERSION);
		}

		@Override
		public void onCreate(SQLiteDatabase db) {
		db.execSQL(QUERY_CREATE_DOCUMENTS);
		db.execSQL(QUERY_CREATE_ROOT_EXTRA);
		db.execSQL(QUERY_CREATE_VIEW_ROOTS);
		}

		@Override
		public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
		throw new UnsupportedOperationException();
		}
		}

		private final MtpDatabaseInternal mDatabase;
		private final Map<String, Integer> mMappingMode = new HashMap<>();
		private final SQLiteDatabase mDatabase;

		@VisibleForTesting
		MtpDatabase(Context context) {
		final OpenHelper helper = new OpenHelper(context);
		mDatabase = helper.getWritableDatabase();
		}

		@VisibleForTesting
		static void deleteDatabase(Context context) {
		SQLiteDatabase.deleteDatabase(context.getDatabasePath(NAME));
		mDatabase = new MtpDatabaseInternal(context);
		}

		@VisibleForTesting
		Cursor queryRoots(String[] columnNames) {
		return mDatabase.query(
		VIEW_ROOTS,
		columnNames,
		COLUMN_ROW_STATE + " IN (?, ?)",
		strings(ROW_STATE_VALID, ROW_STATE_INVALIDATED),
		null,
		null,
		null);
		return mDatabase.queryRoots(columnNames);
		}

		@VisibleForTesting
		Cursor queryRootDocuments(String[] columnNames) {
		return mDatabase.query(
		TABLE_DOCUMENTS,
		columnNames,
		COLUMN_ROW_STATE + " IN (?, ?)",
		strings(ROW_STATE_VALID, ROW_STATE_INVALIDATED),
		null,
		null,
		null);
		return mDatabase.queryRootDocuments(columnNames);
		}

		@VisibleForTesting
		Cursor queryChildDocuments(String[] columnNames, String parentDocumentId) {
		return mDatabase.query(
		TABLE_DOCUMENTS,
		columnNames,
		COLUMN_ROW_STATE + " IN (?, ?) AND " + COLUMN_PARENT_DOCUMENT_ID + " = ?",
		strings(ROW_STATE_VALID, ROW_STATE_INVALIDATED, parentDocumentId),
		null,
		null,
		null);
		return mDatabase.queryChildDocuments(columnNames, parentDocumentId);
		}

		@VisibleForTesting
		@@ -267,7 +101,8 @@ class MtpDatabase {
		}
		mMappingMode.put(
		mappingStateKey,
		startAddingDocuments(SELECTION_ROOT_DOCUMENTS, Integer.toString(deviceId)));
		mDatabase.startAddingDocuments(
		SELECTION_ROOT_DOCUMENTS, Integer.toString(deviceId)));
		}

		@VisibleForTesting
		@@ -278,43 +113,7 @@ class MtpDatabase {
		}
		mMappingMode.put(
		mappingStateKey,
		startAddingDocuments(SELECTION_CHILD_DOCUMENTS, parentDocumentId));
		}

		/**
		* Starts adding new documents.
		* The methods decides mapping mode depends on if all documents under the given parent have MTP
		* identifier or not. If all the documents have MTP identifier, it uses the identifier to find
		* a corresponding existing row. Otherwise it does heuristic.
		*
		* @param selection Query matches valid documents.
		* @param arg Argument for selection.
		* @return Mapping mode.
		*/
		@VisibleForTesting
		private int startAddingDocuments(String selection, String arg) {
		mDatabase.beginTransaction();
		try {
		// Delete all pending rows.
		deleteDocumentsAndRoots(
		selection + " AND " + COLUMN_ROW_STATE + "=?", strings(arg, ROW_STATE_PENDING));

		// Set all documents as invalidated.
		final ContentValues values = new ContentValues();
		values.put(COLUMN_ROW_STATE, ROW_STATE_INVALIDATED);
		mDatabase.update(TABLE_DOCUMENTS, values, selection, new String[] { arg });

		// If we have rows that does not have MTP identifier, do heuristic mapping by name.
		final boolean useNameForResolving = DatabaseUtils.queryNumEntries(
		mDatabase,
		TABLE_DOCUMENTS,
		selection + " AND " + COLUMN_STORAGE_ID + " IS NULL",
		new String[] { arg }) > 0;
		mDatabase.setTransactionSuccessful();
		return useNameForResolving ? MAP_BY_NAME : MAP_BY_MTP_IDENTIFIER;
		} finally {
		mDatabase.endTransaction();
		}
		mDatabase.startAddingDocuments(SELECTION_CHILD_DOCUMENTS, parentDocumentId));
		}

		@VisibleForTesting
		@@ -343,7 +142,7 @@ class MtpDatabase {
		default:
		throw new Error("Unexpected map mode.");
		}
		final long[] documentIds = putDocuments(
		final long[] documentIds = mDatabase.putDocuments(
		valuesList,
		SELECTION_ROOT_DOCUMENTS,
		Integer.toString(deviceId),
		@@ -359,7 +158,7 @@ class MtpDatabase {
		values.put(Root.COLUMN_AVAILABLE_BYTES, root.mFreeSpace);
		values.put(Root.COLUMN_CAPACITY_BYTES, root.mMaxCapacity);
		values.put(Root.COLUMN_MIME_TYPES, "");
		mDatabase.replace(TABLE_ROOT_EXTRA, null, values);
		mDatabase.putRootExtra(values);
		}
		mDatabase.setTransactionSuccessful();
		} finally {
		@@ -388,30 +187,14 @@ class MtpDatabase {
		default:
		throw new Error("Unexpected map mode.");
		}
		putDocuments(valuesList, SELECTION_CHILD_DOCUMENTS, parentId, heuristic, mapColumn);
		mDatabase.putDocuments(
		valuesList, SELECTION_CHILD_DOCUMENTS, parentId, heuristic, mapColumn);
		}

		/**
		* Clears MTP related identifier.
		* It clears MTP's object handle and storage ID that are not stable over MTP sessions and mark
		* the all documents as 'invalidated'. It also remove 'pending' rows as adding is cancelled
		* now.
		*/
		@VisibleForTesting
		void clearMapping() {
		mDatabase.beginTransaction();
		try {
		deleteDocumentsAndRoots(COLUMN_ROW_STATE + " = ?", strings(ROW_STATE_PENDING));
		final ContentValues values = new ContentValues();
		values.putNull(COLUMN_OBJECT_HANDLE);
		values.putNull(COLUMN_STORAGE_ID);
		values.put(COLUMN_ROW_STATE, ROW_STATE_INVALIDATED);
		mDatabase.update(TABLE_DOCUMENTS, values, null, null);
		mDatabase.setTransactionSuccessful();
		mDatabase.clearMapping();
		mMappingMode.clear();
		} finally {
		mDatabase.endTransaction();
		}
		}

		@VisibleForTesting
		@@ -419,13 +202,13 @@ class MtpDatabase {
		final String mappingModeKey = getRootDocumentsMappingStateKey(deviceId);
		switch (mMappingMode.get(mappingModeKey)) {
		case MAP_BY_MTP_IDENTIFIER:
		stopAddingDocuments(
		mDatabase.stopAddingDocuments(
		SELECTION_ROOT_DOCUMENTS,
		Integer.toString(deviceId),
		COLUMN_STORAGE_ID);
		break;
		case MAP_BY_NAME:
		stopAddingDocuments(
		mDatabase.stopAddingDocuments(
		SELECTION_ROOT_DOCUMENTS,
		Integer.toString(deviceId),
		Document.COLUMN_DISPLAY_NAME);
		@@ -441,13 +224,13 @@ class MtpDatabase {
		final String mappingModeKey = getChildDocumentsMappingStateKey(parentId);
		switch (mMappingMode.get(mappingModeKey)) {
		case MAP_BY_MTP_IDENTIFIER:
		stopAddingDocuments(
		mDatabase.stopAddingDocuments(
		SELECTION_CHILD_DOCUMENTS,
		parentId,
		COLUMN_OBJECT_HANDLE);
		break;
		case MAP_BY_NAME:
		stopAddingDocuments(
		mDatabase.stopAddingDocuments(
		SELECTION_CHILD_DOCUMENTS,
		parentId,
		Document.COLUMN_DISPLAY_NAME);
		@@ -458,161 +241,6 @@ class MtpDatabase {
		mMappingMode.remove(mappingModeKey);
		}

		/**
		* Puts the documents into the database.
		* If the mapping mode is not heuristic, it just adds the rows to the database or updates the
		* existing rows with the new values. If the mapping mode is heuristic, it adds some new rows as
		* 'pending' state when that rows may be corresponding to existing 'invalidated' rows. Then
		* {@link #stopAddingDocuments(String, String, String)} turns the pending rows into 'valid'
		* rows.
		*
		* @param valuesList Values that are stored in the database.
		* @param selection SQL where closure to select rows that shares the same parent.
		* @param arg Argument for selection SQL.
		* @param heuristic Whether the mapping mode is heuristic.
		* @return List of Document ID inserted to the table.
		*/
		private long[] putDocuments(
		ContentValues[] valuesList,
		String selection,
		String arg,
		boolean heuristic,
		String mappingKey) {
		mDatabase.beginTransaction();
		try {
		final long[] documentIds = new long[valuesList.length];
		int i = 0;
		for (final ContentValues values : valuesList) {
		final Cursor candidateCursor = mDatabase.query(
		TABLE_DOCUMENTS,
		strings(Document.COLUMN_DOCUMENT_ID),
		selection + " AND " +
		COLUMN_ROW_STATE + "=? AND " +
		mappingKey + "=?",
		strings(arg, ROW_STATE_INVALIDATED, values.getAsString(mappingKey)),
		null,
		null,
		null,
		"1");
		final long rowId;
		if (candidateCursor.getCount() == 0) {
		rowId = mDatabase.insert(TABLE_DOCUMENTS, null, values);
		} else if (!heuristic) {
		candidateCursor.moveToNext();
		final String documentId = candidateCursor.getString(0);
		rowId = mDatabase.update(
		TABLE_DOCUMENTS, values, SELECTION_DOCUMENT_ID, strings(documentId));
		} else {
		values.put(COLUMN_ROW_STATE, ROW_STATE_PENDING);
		rowId = mDatabase.insert(TABLE_DOCUMENTS, null, values);
		}
		// Document ID is a primary integer key of the table. So the returned row
		// IDs should be same with the document ID.
		documentIds[i++] = rowId;
		candidateCursor.close();
		}

		mDatabase.setTransactionSuccessful();
		return documentIds;
		} finally {
		mDatabase.endTransaction();
		}
		}

		/**
		* Maps 'pending' document and 'invalidated' document that shares the same column of groupKey.
		* If the database does not find corresponding 'invalidated' document, it just removes
		* 'invalidated' document from the database.
		* @param selection Query to select rows for resolving.
		* @param arg Argument for selection SQL.
		* @param groupKey Column name used to find corresponding rows.
		*/
		private void stopAddingDocuments(String selection, String arg, String groupKey) {
		mDatabase.beginTransaction();
		try {
		// Get 1-to-1 mapping of invalidated document and pending document.
		final String invalidatedIdQuery = createStateFilter(
		ROW_STATE_INVALIDATED, Document.COLUMN_DOCUMENT_ID);
		final String pendingIdQuery = createStateFilter(
		ROW_STATE_PENDING, Document.COLUMN_DOCUMENT_ID);
		// SQL should be like:
		// SELECT group_concat(CASE WHEN raw_state = 1 THEN document_id ELSE NULL END),
		// group_concat(CASE WHEN raw_state = 2 THEN document_id ELSE NULL END)
		// WHERE device_id = ? AND parent_document_id IS NULL
		// GROUP BY display_name
		// HAVING count(CASE WHEN raw_state = 1 THEN document_id ELSE NULL END) = 1 AND
		// count(CASE WHEN raw_state = 2 THEN document_id ELSE NULL END) = 1
		final Cursor mergingCursor = mDatabase.query(
		TABLE_DOCUMENTS,
		new String[] {
		"group_concat(" + invalidatedIdQuery + ")",
		"group_concat(" + pendingIdQuery + ")"
		},
		selection,
		strings(arg),
		groupKey,
		"count(" + invalidatedIdQuery + ") = 1 AND count(" + pendingIdQuery + ") = 1",
		null);

		final ContentValues values = new ContentValues();
		while (mergingCursor.moveToNext()) {
		final String invalidatedId = mergingCursor.getString(0);
		final String pendingId = mergingCursor.getString(1);

		// Obtain the new values including the latest object handle from mapping row.
		getFirstRow(
		TABLE_DOCUMENTS,
		SELECTION_DOCUMENT_ID,
		new String[] { pendingId },
		values);
		values.remove(Document.COLUMN_DOCUMENT_ID);
		values.put(COLUMN_ROW_STATE, ROW_STATE_VALID);
		mDatabase.update(
		TABLE_DOCUMENTS,
		values,
		SELECTION_DOCUMENT_ID,
		new String[] { invalidatedId });

		getFirstRow(
		TABLE_ROOT_EXTRA,
		SELECTION_ROOT_ID,
		new String[] { pendingId },
		values);
		if (values.size() > 0) {
		values.remove(Root.COLUMN_ROOT_ID);
		mDatabase.update(
		TABLE_ROOT_EXTRA,
		values,
		SELECTION_ROOT_ID,
		new String[] { invalidatedId });
		}

		// Delete 'pending' row.
		deleteDocumentsAndRoots(SELECTION_DOCUMENT_ID, new String[] { pendingId });
		}
		mergingCursor.close();

		// Delete all invalidated rows that cannot be mapped.
		deleteDocumentsAndRoots(
		COLUMN_ROW_STATE + " = ? AND " + selection,
		strings(ROW_STATE_INVALIDATED, arg));

		// The database cannot find old document ID for the pending rows.
		// Turn the all pending rows into valid state, which means the rows become to be
		// valid with new document ID.
		values.clear();
		values.put(COLUMN_ROW_STATE, ROW_STATE_VALID);
		mDatabase.update(
		TABLE_DOCUMENTS,
		values,
		COLUMN_ROW_STATE + " = ? AND " + selection,
		strings(ROW_STATE_PENDING, arg));
		mDatabase.setTransactionSuccessful();
		} finally {
		mDatabase.endTransaction();
		}
		}

		/**
		* Gets {@link ContentValues} for the given root.
		* @param values {@link ContentValues} that receives values.
		@@ -675,51 +303,6 @@ class MtpDatabase {
		values.put(Document.COLUMN_SIZE, info.getCompressedSize());
		}

		/**
		* Obtains values of the first row for the query.
		* @param values ContentValues that the values are stored to.
		* @param table Target table.
		* @param selection Query to select rows.
		* @param args Argument for query.
		*/
		private void getFirstRow(String table, String selection, String[] args, ContentValues values) {
		values.clear();
		final Cursor cursor = mDatabase.query(table, null, selection, args, null, null, null, "1");
		if (cursor.getCount() == 0) {
		return;
		}
		cursor.moveToNext();
		DatabaseUtils.cursorRowToContentValues(cursor, values);
		cursor.close();
		}

		/**
		* Deletes a document, and its root information if the document is a root document.
		* @param selection Query to select documents.
		* @param args Arguments for selection.
		*/
		private void deleteDocumentsAndRoots(String selection, String[] args) {
		mDatabase.beginTransaction();
		try {
		mDatabase.delete(
		TABLE_ROOT_EXTRA,
		Root.COLUMN_ROOT_ID + " IN (" + SQLiteQueryBuilder.buildQueryString(
		false,
		TABLE_DOCUMENTS,
		new String[] { Document.COLUMN_DOCUMENT_ID },
		selection,
		null,
		null,
		null,
		null) + ")",
		args);
		mDatabase.delete(TABLE_DOCUMENTS, selection, args);
		mDatabase.setTransactionSuccessful();
		} finally {
		mDatabase.endTransaction();
		}
		}

		private String getRootDocumentsMappingStateKey(int deviceId) {
		return "RootDocuments/" + deviceId;
		}
		@@ -727,29 +310,4 @@ class MtpDatabase {
		private String getChildDocumentsMappingStateKey(String parentDocumentId) {
		return "ChildDocuments/" + parentDocumentId;
		}

		/**
		* Converts values into string array.
		* @param args Values converted into string array.
		* @return String array.
		*/
		private static String[] strings(Object... args) {
		final String[] results = new String[args.length];
		for (int i = 0; i < args.length; i++) {
		results[i] = Objects.toString(args[i]);
		}
		return results;
		}

		/**
		* Gets SQL expression that represents the given value or NULL depends on the row state.
		* @param state Expected row state.
		* @param a SQL value.
		* @return Expression that represents a if the row state is expected one, and represents NULL
		* otherwise.
		*/
		private static String createStateFilter(int state, String a) {
		return "CASE WHEN " + COLUMN_ROW_STATE + " = " + Integer.toString(state) +
		" THEN " + a + " ELSE NULL END";
		}
		}

packages/MtpDocumentsProvider/src/com/android/mtp/MtpDatabaseConstants.java

0 → 100644

+141 −0

File added.

Preview size limit exceeded, changes collapsed.

packages/MtpDocumentsProvider/src/com/android/mtp/MtpDatabaseInternal.java

0 → 100644

+391 −0

File added.

Preview size limit exceeded, changes collapsed.

packages/MtpDocumentsProvider/tests/src/com/android/mtp/MtpDatabaseTest.java

+10 −16

File changed.

Preview size limit exceeded, changes collapsed.