Restorable SQLiteDatabase

RestorableSQLiteDatabase is a wrapper to replicate android's SQLiteDatabase class with restoring capability. This wrapper makes it possible to undo changes made after execution of SQL queries.

How to use

Use Gradle

Reference library using this dependency in your module's build.gradle file:

dependencies {
    compile 'github.yaa110.db:restorablesqlitedatabase:0.1.0'
}

or Use Maven

<dependency>
	<groupId>github.yaa110.db</groupId>
	<artifactId>restorablesqlitedatabase</artifactId>
	<version>0.1.0</version>
	<type>aar</type>
</dependency>

Example: Undoing deleted rows

First, create a subclass of SQLiteOpenHelper:

public class DbHelper extends SQLiteOpenHelper {

    public DbHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(
                "CREATE TABLE IF NOT EXISTS " + TABLE_NAME + " (" +
                        COLUMN_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
                        COLUMN_TITLE + " TEXT" +
                        ");"
        );
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int old_version, int new_version) {
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
        onCreate(db);
    }

}

Then, use RestorableSQLiteDatabase:

HashMap<String, String> tableRowid = new HashMap<>();
tableRowid.put(TABLE_NAME, COLUMN_ROWID);

DbHelper helper = new DbHelper(this);

RestorableSQLiteDatabase db = new RestorableSQLiteDatabase(helper, tableRowid);

// Delete some rows
db.delete(
        TABLE_NAME,
        COLUMN_TITLE + " = ?",
        new String[] {"demo"},
        "DELETION_TAG"
);

// Undoing deletion
db.restore("DELETION_TAG");

Documentation

public static RestorableSQLiteDatabase getInstance(SQLiteDatabase mSQLiteDatabase, HashMap<String, String> tableRowid)

Constructs a new instance of the RestorableSQLiteDatabase only if no instance is constructed.

Parameters

• mSQLiteDatabase the instance of the SQLiteDatabase to be wrapped.
• tableRowid maps the table name to its ROWID column name.

public static <T extends SQLiteOpenHelper> RestorableSQLiteDatabase getInstance(T helper, HashMap<String, String> tableRowid)

Constructs a new instance of the RestorableSQLiteDatabase only if no instance is constructed.

Parameters

• helper the instance of the SQLiteOpenHelper to open a database using its getWritableDatabase method.
• tableRowid maps the table name to its ROWID column name.

public static RestorableSQLiteDatabase getNewInstance(SQLiteDatabase mSQLiteDatabase, HashMap<String, String> tableRowid)

Constructs a new instance of the RestorableSQLiteDatabase.

Parameters

• mSQLiteDatabase the instance of the SQLiteDatabase to be wrapped.
• tableRowid maps the table name to its ROWID column name.

public static <T extends SQLiteOpenHelper> RestorableSQLiteDatabase getNewInstance(T helper, HashMap<String, String> tableRowid)

Constructs a new instance of the RestorableSQLiteDatabase.

Parameters

• helper the instance of the SQLiteOpenHelper to open a database using its getWritableDatabase method.
• tableRowid maps the table name to its ROWID column name.

public void close()

Closes the SQLite database. Use the reopen methods to reopen the SQLite database.

public boolean containsTag(String tag)

Checks if the hash table contains the tag.

Parameters

• tag possible tag of restoring query.

Returns

True if the hash table contains the tag; false otherwise.

Throws

• IllegalArgumentException if the tag is null.

public int delete(String table, String whereClause, String[] whereArgs, String tag)

Replicates the [delete](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#delete(java.lang.String, java.lang.String, java.lang.String[])) method of the SQLiteDatabase.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public ArrayList<String> getQueries(String tag)

Provides the query to which the tag is mapped.

Parameters

• tag possible tag of restoring query.

Returns

The queries to which the tag is mapped, or null if the hash table contains no mapping for the tag.

Throws

• IllegalArgumentException if the tag is null.

public SQLiteDatabase getSQLiteDatabase()

Provides the instance of wrapped SQLiteDatabase.

Returns

The instance of wrapped SQLiteDatabase.

public Hashtable<String, ArrayList<String[]>> getTagQueryParameters()

Provides the parameters hash table.

Returns

The parameters hash table.

public Hashtable<String, ArrayList<String>> getTagQueryTable()

Provides the hash table.

Returns

The hash table.

public long insert(String table, String nullColumnHack, ContentValues values, String tag)

Replicates the [insert](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#insert(java.lang.String, java.lang.String, android.content.ContentValues)) method of the SQLiteDatabase.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public long insertOrThrow(String table, String nullColumnHack, ContentValues values, String tag) throws SQLException

Replicates the [insertOrThrow](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#insertOrThrow(java.lang.String, java.lang.String, android.content.ContentValues)) method of the SQLiteDatabase.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public long insertWithOnConflict(String table, String nullColumnHack, ContentValues initialValues, int conflictAlgorithm, String tag)

Replicates the [insertWithOnConflict](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#insertWithOnConflict(java.lang.String, java.lang.String, android.content.ContentValues, int)) method of the SQLiteDatabase.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public Cursor rawQuery(String sql, String[] selectionArgs, String tag) throws JSQLParserException, ClassCastException

Replicates the [rawQuery](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#rawQuery(java.lang.String, java.lang.String[])) method of the SQLiteDatabase.

Unlike the rawQuery of the SQLiteDatabase, there is no need to call the moveToFirst method of the returned Cursor to apply SQL query.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public Cursor rawQuery(String sql, String[] selectionArgs, CancellationSignal cancellationSignal, String tag) throws JSQLParserException, ClassCastException

Replicates the [rawQuery](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#rawQuery(java.lang.String, java.lang.String[], android.os.CancellationSignal)) method of the SQLiteDatabase.

Unlike the rawQuery of the SQLiteDatabase, there is no need to call the moveToFirst method of the returned Cursor to apply SQL query.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public void reopen(SQLiteDatabase mSqLiteDatabase)

Reopens the SQLite database.

Parameters

• mSqLiteDatabase the instance of the SQLiteDatabase to be wrapped.

public <T extends SQLiteOpenHelper> void reopen(T helper)

Reopens the SQLite database.

Parameters

• helper the instance of the SQLiteOpenHelper to open a database using its getWritableDatabase method.

public long replace(String table, String nullColumnHack, ContentValues initialValues, String tag)

Replicates the [replace](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#replace(java.lang.String, java.lang.String, android.content.ContentValues)) method of the SQLiteDatabase.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public long replaceOrThrow(String table, String nullColumnHack, ContentValues initialValues, String tag) throws SQLException

Replicates the [replaceOrThrow](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#replaceOrThrow(java.lang.String, java.lang.String, android.content.ContentValues)) method of the SQLiteDatabase.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public int restore(String tag)

Restores the SQL queries to which the tag is mapped.

Parameters

• tag the tag mapped to restoring queries.

Returns

Possible number of restored queries to which tag is mapped.

public int restore(String[] tags)

Restores the queries to which each tag is mapped.

Parameters

• tags an array of tags mapped to restoring SQL queries.

Returns

Possible number of restored queries to which tag is mapped.

public int restore(Set<String> tags)

Restores the queries to which each tag is mapped.

Parameters

• tags a set of tags mapped to restoring SQL queries.

Returns

Possible number of restored queries to which tag is mapped.

public int restoreAll()

Restores all restoring SQL queries.

Returns

Possible number of restored queries to which tag is mapped.

public void setTagQueryParameters(Hashtable<String, ArrayList<String[]>> tagQueryParameters)

Changes the parameters hash table.

Parameters

• tagQueryParameters the substitute hash table.

public void setTagQueryTable(Hashtable<String, ArrayList<String>> tagQueryTable)

Changes the hash table.

Parameters

• tagQueryTable the substitute hash table.

public Set<String> tagSet()

Provides a Set view of the tags contained in the hash table.

Returns

a Set view of the tags contained in the hash table.

public int update(String table, ContentValues values, String whereClause, String[] whereArgs, String tag)

Replicates the [update](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#update(java.lang.String, android.content.ContentValues, java.lang.String, java.lang.String[])) method of the SQLiteDatabase.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

public int updateWithOnConflict(String table, ContentValues values, String whereClause, String[] whereArgs, int conflictAlgorithm, String tag)

Replicates the [updateWithOnConflict](http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html#updateWithOnConflict(java.lang.String, android.content.ContentValues, java.lang.String, java.lang.String[], int)) method of the SQLiteDatabase.

Parameters

• tag the tag to be mapped to the restoring query.

Throws

• IllegalArgumentException if the tag is null.

Dependencies

JSqlParser parses an SQL statement and translate it into a hierarchy of Java classes. JSqlParser is licensed under the LGPL V2.1.

License

RestorableSQLiteDatabase is licensed under the MIT License.