error copying my database file from assets folder into my application

Question

I have database with name: MyDb.sqlite

then in my database file have 2 table

1 table of users

row1 id_users (primary key,auto increment,int)

row2 username (varchar)

and value is empty

2 table of android_metabata

row1 locale (text) then values is en_US

I am putting my database into assets folder

JAVA Class

public class DataBaseHelper extends SQLiteOpenHelper{

    private static String DB_PATH = "/data/data/com.example/databases/";

    private static String DB_NAME = "MyDb.db";

    private SQLiteDatabase myDataBase; 

    private final Context myContext;

    private static DataBaseHelper sInstance = null;


    public DataBaseHelper(Context context) {

        super(context, DB_NAME, null, 1);
        this.myContext = context;
    }   

    public void createDataBase() throws IOException{

        boolean dbExist = checkDataBase();

        if(dbExist){
            //do nothing - database already exist
        }else{

            this.getReadableDatabase();

            try {

                copyDataBase();

            } catch (IOException e) {

                throw new Error("Error copying database");

            }
        }

    }

    private boolean checkDataBase(){

        SQLiteDatabase checkDB = null;

        try{
            String myPath = DB_PATH + DB_NAME;
            checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);

        }catch(SQLiteException e){

            //database does't exist yet.

        }

        if(checkDB != null){

            checkDB.close();

        }

        return checkDB != null ? true : false;
    }

    private void copyDataBase() throws IOException{

        //Open your local db as the input stream
        InputStream myInput = myContext.getAssets().open(DB_NAME);

        // Path to the just created empty db
        String outFileName = DB_PATH + DB_NAME;


        OutputStream myOutput = new FileOutputStream(outFileName);


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

        //Close the streams
        myOutput.flush();
        myOutput.close();
        myInput.close();

    }

    public void openDataBase() throws SQLException{


        String myPath = DB_PATH + DB_NAME;
        myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);

    }
    public Cursor select(String query) throws SQLException {
        return myDataBase.rawQuery(query, null);
    }


    public void insert(String table, ContentValues values) throws SQLException {
        myDataBase.insert(table, null, values);
    }


    public void delete(String table, String where) throws SQLException {

        myDataBase.delete(table, where, null);

    }


    public void update(String table, ContentValues values, String where) {

        myDataBase.update(table, values, where, null);

    }
    public void sqlCommand(String command) {
        myDataBase.execSQL(command);
    }

    @Override
    public synchronized void close() {

            if(myDataBase != null)
                myDataBase.close();

            super.close();

    }

    @Override
    public void onCreate(SQLiteDatabase db) {

    }

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

    }

    public static DataBaseHelper instance() {
        /*
        if (sInstance == null) {
            sInstance = new DataBaseManager();
        }
        */
        return sInstance;
    }

}

process copying is successfull then i am look at folder data/data/my_package_name/databases using this tutorial

but my table users can't copy and my table android_metadata copying successfull,why?

thanks.

http://stackoverflow.com/questions/9109438/how-to-use-an-existing-database-with-an-android-application/9109728#9109728 — Yaqub Ahmad, Feb 12 '13 at 17:25
my table user can't copying,,,, i am using android GIngerbread and using compiler jellybean. what is problem with compiler?or other? — Ash, Feb 12 '13 at 17:45

score 1 · Accepted Answer · edited Feb 13 '13 at 12:44

Try this code:

public DataBaseHelper(Context context)
    {
        super(context, DB_NAME, null, 1);
        this.mContext = context;
        DB_PATH="/data/data/" + context.getPackageName() + "/databases/";
    }   

    public void openDataBase() throws SQLException
    {
        Log.e("Open", "open Database");
        mDbHelper = new DataBaseHelper(mContext);
        mDataBase = mDbHelper.getWritableDatabase();
    }
    @Override
    public synchronized SQLiteDatabase getWritableDatabase() 
  {
      SQLiteDatabase db = null;

        if (!existsDataBase()) {
            try 
            {
                copyDataBase ();
                db = super.getWritableDatabase();

            } catch(Exception ex) 
            {
                ex.printStackTrace();
                Log.e("Database Log", DB_PATH + " failed to copy correctly. " + ex.getLocalizedMessage());
            }
        }
        else {
            db = super.getWritableDatabase();
        }

        return db;

  }

private void copyDataBase() throws IOException {

        Log.e("copyDataBase", " called");
        // Open your local db as the input stream
        InputStream myInput = mContext.getAssets().open(DB_NAME);
        // Path to the just created empty db
        String outFileName = DB_PATH + DB_NAME;
        mDataBase=mContext.openOrCreateDatabase(DB_PATH+DB_NAME, Context.MODE_PRIVATE, null );
        // Open the empty db as the output stream
        OutputStream myOutput = new FileOutputStream(outFileName);
        // transfer bytes from the inputfile to the outputfile
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer)) > 0) {
            myOutput.write(buffer, 0, length);
        }



        // Close the streams
        myOutput.flush();
        myOutput.close();
        myInput.close();
        //

    }

// make Call to your DataBaseHelper class like this: mDatabase= new DataBaseHelper (this); mDatabase.openDataBase();//it will copy the existing db and if you need to add more tables do that inside openDatabase method

score 0 · Answer 2 · edited Oct 14 '16 at 03:48

Just put this line in your code: myContext.openOrCreateDatabase(DB_PATH+DB_NAME, Context.MODE_PRIVATE, null );

your updated copyDataBase() method becomes:

private void copyDataBase() throws IOException{

    //Open your local db as the input stream
    InputStream myInput = myContext.getAssets().open(DB_NAME);

    // Path to the just created empty db
    String outFileName = DB_PATH + DB_NAME;

    myDataBase=myContext.openOrCreateDatabase(DB_PATH+DB_NAME, Context.MODE_PRIVATE, null );

    OutputStream myOutput = new FileOutputStream(outFileName);


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

    //Close the streams
    myOutput.flush();
    myOutput.close();
    myInput.close();

}

error copying my database file from assets folder into my application

2 Answers2