//This My MYDBHandler File
public class MyDBHandler extends SQLiteOpenHelper {
private static String DB_PATH = "/data/data/http://ift.tt/1WUsOXk";
private static String DB_NAME = "question";
private SQLiteDatabase myDataBase;
private final Context myContext;
Constructor Takes and keeps a reference of the passed context in order to access to the application assets and resources.
public MyDBHandler(Context context) {
super(context, DB_NAME, null,1);
this.myContext = context;
this.createDatabase();
}
Creates a empty database on the system and rewrites it with your own database.
public void createDatabase() {
try {
boolean dbExist = checkDataBase();
if(dbExist){
//do nothing - database already exist
}else{
By calling this method and empty database will be created into the default system path
of application so we are gonna be able to overwrite that database with our database.
this.getReadableDatabase();
copyDataBase();
}
}
catch (Exception e) {
}
}
Check if the database already exist to avoid re-copying the file each time you open the application. @return true if it exists, false if it doesn't
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;
}
Copies your database from your local assets-folder to the just created empty database in the system folder, from where it can be accessed and handled. This is done by transfering bytestream.
private void copyDataBase(){
try{
//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;
//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();
}
catch (Exception e) {
//catch exception
}
}
public SQLiteDatabase openDataBase() throws SQLException{
String myPath = DB_PATH + DB_NAME;
myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READWRITE);
return myDataBase;
}
@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) {
}
}
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