Copy database from internal storage to data directory of my application

Question

I want to copy the an database file from internal storage directory to data folder of my application.

Here is my code :

public static void copyDatabase(Context applicationContext){
    try {
        File sd = Environment.getExternalStorageDirectory();
        File data = Environment.getDataDirectory();
        if (data.canWrite()) {
            String dbPath = "/data/data/" + "my.package.here" + "/databases/dbname";
            String actualDBPath = "dbname.sqlite";
            File finalDB = new File(dbPath);
            File actualDB = new File(sd, actualDBPath);
            if (actualDB.exists()) {
                FileChannel src = new FileInputStream(actualDB).getChannel();
                FileChannel dst = new FileOutputStream(finalDB).getChannel();
                dst.transferFrom(src, 0, src.size());
                src.close();
                dst.close();
            }
        }
        Toast.makeText(applicationContext, "Save completed !!.", Toast.LENGTH_SHORT).show();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

While i call the copydatabase function, when the compiler reaches data.canWrite() it returns false. How do i fix it ?

score 0 · Accepted Answer · edited May 23 '17 at 11:52

Ship an application with a database

public class PlanDetailsSQLiteOpenHelper extends SQLiteOpenHelper {
private static final String TAG = "SQLiteOpenHelper";

private final Context context;
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "my_custom_db";

private boolean createDb = false, upgradeDb = false;

public PlanDetailsSQLiteOpenHelper(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
    this.context = context;
}

/**
 * Copy packaged database from assets folder to the database created in the
 * application package context.
 * 
 * @param db
 *            The target database in the application package context.
 */
private void copyDatabaseFromAssets(SQLiteDatabase db) {
    Log.i(TAG, "copyDatabase");
    InputStream myInput = null;
    OutputStream myOutput = null;
    try {
        // Open db packaged as asset as the input stream
        myInput = context.getAssets().open("path/to/shipped/db/file");

        // Open the db in the application package context:
        myOutput = new FileOutputStream(db.getPath());

        // Transfer db file contents:
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer)) > 0) {
            myOutput.write(buffer, 0, length);
        }
        myOutput.flush();

        // Set the version of the copied database to the current
        // version:
        SQLiteDatabase copiedDb = context.openOrCreateDatabase(
            DATABASE_NAME, 0, null);
        copiedDb.execSQL("PRAGMA user_version = " + DATABASE_VERSION);
        copiedDb.close();

    } catch (IOException e) {
        e.printStackTrace();
        throw new Error(TAG + " Error copying database");
    } finally {
        // Close the streams
        try {
            if (myOutput != null) {
                myOutput.close();
            }
            if (myInput != null) {
                myInput.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
            throw new Error(TAG + " Error closing streams");
        }
    }
}

@Override
public void onCreate(SQLiteDatabase db) {
    Log.i(TAG, "onCreate db");
    createDb = true;
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    Log.i(TAG, "onUpgrade db");
    upgradeDb = true;
}

@Override
public void onOpen(SQLiteDatabase db) {
    Log.i(TAG, "onOpen db");
    if (createDb) {// The db in the application package
        // context is being created.
        // So copy the contents from the db
        // file packaged in the assets
        // folder:
        createDb = false;
        copyDatabaseFromAssets(db);

    }
    if (upgradeDb) {// The db in the application package
        // context is being upgraded from a lower to a higher version.
        upgradeDb = false;
        // Your db upgrade logic here:
    }
}
}

Copy database from internal storage to data directory of my application

1 Answers1