Memory exhausted while trying to get data from database (Android)
I am trying to get some information from my database. I am new to android. I have a database creation class called "Database" and a database access class called "Database_Acesso". They look like this:
Database.java: package workshopee.ct.ufrn.br.ssmonitor;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class Database extends SQLiteOpenHelper{
private static final int versao_db = 1;
private static final String nome_db = "ssmonitor_db";
private static final String table1 = "phone";
private static final String id = "_id";
private static final String longitude = "longitude";
private static final String latitude = "latitude";
private static final String forca_torres = "qtdtorres";
private static final String forca_dbm = "dbm";
private static final String mcc = "mcc";
private static final String mnc = "mnc";
private static final String phone_type = "phone_type";
private static final String operadora = "operadora";
private static final String network_type = "networkType";
private static final String cid = "cid";
private static final String lac = "lac";
public Database(Context context) {
super(context, nome_db, null, versao_db);
}
@Override
public void onCreate(SQLiteDatabase db) {
String criarTabela = "CREATE TABLE " + table1 + "("
+ id + " INTEGER PRIMARY KEY AUTOINCREMENT," + longitude + " REAL,"
+ latitude + " REAL," + forca_torres + " INTEGER," + forca_dbm + " REAL," + mcc + " INTEGER,"
+ mnc + " INTEGER," + phone_type + " TEXT," + operadora + " TEXT," + network_type + " INTEGER," + cid + " INTEGER,"
+ lac + " INTEGER )";
db.execSQL(criarTabela);
}
@Override
public void onUpgrade(SQLiteDatabase db, int versao_ant, int versao_nv) {
Log.w(Database.class.getName(),
"Atualizando o banco de dados da versão " + versao_ant + " para "
+ versao_nv + ", isso apagará os dados antigos.");
db.execSQL("DROP TABLE IF EXISTS " + table1 + ";");
onCreate(db);
}
public void clear (SQLiteDatabase db) {
Log.w(Database.class.getName(),
"Apagando informações salvas anteriormente.");
db.execSQL("DROP TABLE IF EXISTS " + table1 + ";");
onCreate(db);
}
}
Database_Acesso.java:
package workshopee.ct.ufrn.br.ssmonitor;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import java.util.ArrayList;
import java.util.List;
public class Database_Acesso {
private SQLiteDatabase db;
public Database_Acesso(Context context) {
Database aux_db = new Database(context);
db = aux_db.getWritableDatabase();
}
public void inserir_phone (Phone ph) {
ContentValues valores = new ContentValues();
valores.put("longitude",ph.getLongitude());
valores.put("latitude", ph.getLatitude());
valores.put("qtdtorres", ph.getTorres());
valores.put("dbm", ph.getDbm());
valores.put("mcc", ph.getMcc());
valores.put("mnc", ph.getMnc());
valores.put("phone_type", ph.getPhoneType());
valores.put("operadora", ph.getOperadora());
valores.put("cid",ph.getCid());
valores.put("lac",ph.getLac());
db.insert("phone", null, valores);
}
public List<Phone> buscar_phone () {
List<Phone> lista = new ArrayList<Phone>();
String[] colunas = new String[]{"_id", "longitude", "latitude", "qtdtorres", "dbm",
"mcc", "mnc", "phone_type", "operadora", "networkType", "cid", "lac"};
Cursor cursor = db.query("phone", colunas, null, null, null, null,"_id ASC");
if (cursor.getCount() > 0) {
cursor.moveToFirst();
}
do {
Phone p = new Phone();
p.setId(cursor.getLong(0));
p.setLongitude(cursor.getDouble(1));
p.setLatitude(cursor.getDouble(2));
p.setTorres(cursor.getInt(3));
p.setDbm(cursor.getInt(4));
p.setMcc(cursor.getInt(5));
p.setMnc(cursor.getInt(6));
p.setPhoneType(cursor.getString(7));
p.setOperadora(cursor.getString(8));
p.setNetWorkType(cursor.getString(9));
p.setCid(cursor.getInt(10));
p.setLac(cursor.getInt(11));
lista.add(p);
} while (!cursor.isLast());
return lista;
}
}
Here is the part of my MainActivity that inserts the data:
database_acesso.inserir_phone(cell);
Where database_acesso is the Database_acesso instance and cell is the phone instance.
And this is how I am trying to get the information: TextView list_text_view = (TextView) rootView.findViewById (R.id.list_text_view); List list = main.database_acesso.buscar_phone (); list_text_view.append ("-" + list.size ());
I am using fragments, so "main" is an instance of MainActivity. When I try to execute it, I get the following error:
java.lang.OutOfMemoryError: [memory exhausted]
at dalvik.system.NativeStart.main(Native Method)
This is a complete stack trace.
Any ideation to address this issue?
thank.
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You never call cursor.moveToNext()
in your loop do { ... } while ()
, so you are constantly creating new objects Phone
until you are done.
Perhaps the best way to write a loop is:
Cursor cursor = db.query("phone", colunas, null, null, null, null,"_id ASC");
while (cursor.moveToNext())
{
// Do stuff
}
... because it moveToNext()
returns a boolean indicating whether it has reached the end. It also saves call overhead getCount()
.
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