Can't copy SQLite database from assets

Question

I try to copy SQLite database from assets directory to access it later. But I fail to do it!

public class DatabaseAdapter {
    private static String DB_PATH         


        

Answer 1

Please check the databases folder before your OutputStream.

like this,

File databaseFile = new File(context.getFilesDir().getAbsolutePath()
            .replace("files", "databases"));

// check if databases folder exists, if not create it.
if (!databaseFile.exists()){
    databaseFile.mkdir();
}

Answer 2

I use this Helper and works fine:

public class DBHelper extends SQLiteOpenHelper{

private final static String DB_PATH = "/data/data/[YOUR PACKAGE HERE]/databases/";

String dbName;
Context context;

File dbFile;

public DBHelper(Context context, String dbName, CursorFactory factory,
        int version) {
    super(context, dbName, factory, version);
    this.context = context;
    this.dbName = dbName;
    dbFile= new File(DB_PATH + dbName);
}

@Override
public synchronized SQLiteDatabase getWritableDatabase() {

    if(!dbFile.exists()){
        SQLiteDatabase db = super.getWritableDatabase();
        copyDataBase(db.getPath());
    }
    return super.getWritableDatabase();
}

@Override
public synchronized SQLiteDatabase getReadableDatabase() {
    if(!dbFile.exists()){
        SQLiteDatabase db = super.getReadableDatabase();
        copyDataBase(db.getPath());
    }
    return super.getReadableDatabase();
}

@Override
public void onCreate(SQLiteDatabase db) {}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {}

private void copyDataBase(String dbPath){
    try{
        InputStream assestDB = context.getAssets().open("databases/"+dbName);

        OutputStream appDB = new FileOutputStream(dbPath,false);

        byte[] buffer = new byte[1024];
        int length;
        while ((length = assestDB.read(buffer)) > 0) {
            appDB.write(buffer, 0, length);
        }

        appDB.flush();
        appDB.close();
        assestDB.close();
    }catch(IOException e){
        e.printStackTrace();
    }

}

}

Take into account that the file extension of a database is .db and that my databases are into assets/databases/

Answer 3

public static void copyDatabase(final Context ctx, String dbName) {
    if (ctx != null) {
        File f = ctx.getDatabasePath(dbName);
        if (!f.exists()) {

            // check databases exists
            if (!f.getParentFile().exists())
                f.getParentFile().mkdir();

            try {
                InputStream in = ctx.getAssets().open(dbName);
                OutputStream out = new FileOutputStream(f.getAbsolutePath());

                byte[] buffer = new byte[1024];
                int length;
                while ((length = in.read(buffer)) > 0) {
                    out.write(buffer, 0, length);
                }
                in.close();
                out.close();
                Logger.i("Database copy successed! " + f.getPath());
            } catch (Exception ex) {
                Logger.e(ex);
            }
        }
    }
}

Answer 4

I have the same problem and I have fixed it with another approach. At the beginning, I declared the database path as everyone did:

dbPath="data/data/<my package name>/databases/data.db"

This is an exactly path, no mistake. But It' always fail when I try to open the OutPutFileStream to copy database. I don't know why. And then, I change the way to open the database as below:

dbPath = context.getDatabasePath(dbName);
OutputStream myOutput = new FileOutputStream(dbPath.getAbsolutePath());

The problem has ben solved. So surprise.

Hope this helps.