In this tutorial, I am going to create the database by using the existing database. In order to do this , place your existing database into the “assets” folder. The DBAdapter.java file is as follows.
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
public class DBAdapter extends SQLiteOpenHelper {
private static String DB_PATH = "";
private static final String DB_NAME = "game.db";
private SQLiteDatabase myDataBase;
private final Context myContext;
private static DBAdapter mDBConnection;
private DBAdapter(Context context) {
super(context, DB_NAME, null, 1);
this.myContext = context;
DB_PATH = "/data/data/"+ context.getApplicationContext().getPackageName() + "/databases/";
}
public static synchronized DBAdapter getDBAdapterInstance(Context context) {
if (mDBConnection == null) {
mDBConnection = new DBAdapter(context);
}
return mDBConnection;
}
public void createDataBase() throws IOException {
boolean dbExist = checkDataBase();
if (dbExist) {
// do nothing - database already exist
} else {
// By calling following method
// 1) an empty database will be created into the default system path of your application
// 2) than we overwrite that database with our database.
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;
// 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();
}
public void openDataBase() throws SQLException {
String myPath = DB_PATH + DB_NAME;
myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READWRITE);
}
@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) {
}
// ----------------------- DATABASE Operations ------------------------------
public long insertPuzzle(String problem,String solution,String level, int status)
{
ContentValues initialValues = new ContentValues();
initialValues.put("problem", problem);
initialValues.put("solution",solution);
initialValues.put("level",level);
initialValues.put("status",status);
return myDataBase.insert("puzzles", null, initialValues);
}
}
In the Activity class call like this
private DBAdapter db=null;
db=DBAdapter.getDBAdapterInstance(this);
/*try {
db.createDataBase();
} catch (IOException e) {
e.printStackTrace();
}*/
db.openDataBase();
db.insertPuzzle(..,..,..);
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