Question

I’m trying to insert data into a database when there is no network, but it gives me a NullPointerException. When it goes online, it gives some others and crashes my app.

LogCat Error

    10-13 01:27:07.614: E/Service(13862): Service Created.. 
    10-13 01:27:08.054: E/Service Started(13862): Successful
    10-13 01:27:08.094: E/Insertion(13862): java.lang.NullPointerException
    10-13 01:27:09.134: E/Service Network(13862): Network is offline
    10-13 01:27:14.174: E/Service Network(13862): Network is offline
    10-13 01:28:29.154: E/Service Network(13862): Network is offline
    10-13 01:28:35.924: E/Service Network(13862): Network is offline
    10-13 01:28:39.174: E/Service Network(13862): Network is online
    10-13 01:28:39.204: E/AndroidRuntime(13862): FATAL EXCEPTION: Timer-0
    10-13 01:28:39.204: E/AndroidRuntime(13862): java.lang.NullPointerException
    10-13 01:28:39.204: E/AndroidRuntime(13862):    at com.remote.synchronizer.haris.SQLiteAdapter.getAllContacts(SQLiteAdapter.java:94)
    10-13 01:28:39.204: E/AndroidRuntime(13862):    at com.remote.synchronizer.haris.OfflineDataService.DataSender(OfflineDataService.java:96)
    10-13 01:28:39.204: E/AndroidRuntime(13862):    at com.remote.synchronizer.haris.OfflineDataService.access$0(OfflineDataService.java:90)
    10-13 01:28:39.204: E/AndroidRuntime(13862):    at com.remote.synchronizer.haris.OfflineDataService$1.run(OfflineDataService.java:67)
    10-13 01:28:39.204: E/AndroidRuntime(13862):    at java.util.Timer$TimerImpl.run(Timer.java:284)

OfflineDataService.java

package com.remote.synchronizer.haris;

import java.util.ArrayList;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import org.apache.http.NameValuePair;

import android.app.IntentService;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.util.Log;

public class OfflineDataService extends IntentService {

    boolean wifi,edge;
    private Timer timer= new Timer();
    SQLiteDatabase db;
    String un,shop,city,date,order;
    private SQLiteAdapter mySQLiteAdapter;
    Cursor cursor;

    public OfflineDataService() {
        super("OfflineDataService");
    }

    @Override   
    public void onCreate() {

        super.onCreate();
        Log.e("Service", "Service Created.. ");

         mySQLiteAdapter = new SQLiteAdapter(this);
         mySQLiteAdapter.getWritableDatabase();

}   

    @Override
    protected void onHandleIntent(Intent intent) {

        Bundle bundle=intent.getExtras();
        un=bundle.getString("un");
        shop=bundle.getString("shop");
        city=bundle.getString("city");
        date=bundle.getString("date");
        order=bundle.getString("order");

        Log.e("Service Started", "Successful");

        //Inserting New Record
        mySQLiteAdapter.insert(un,shop,city,date,order);

        timer.scheduleAtFixedRate(new TimerTask(){

            @Override
            public void run() {

                //Checking network connectivity
                   wifi=NetworkInfo.Wifi(OfflineDataService.this);
                   edge=NetworkInfo.EDGE(OfflineDataService.this);

                       if(wifi==true||edge==true)
                       {
                           Log.e("Service Network", "Network is online");
                           DataSender();
                       }
                       else
                       {
                           Log.e("Service Network", "Network is offline");
                       }
            }

        }, 1000, 5000);


    }

    /*@Override
    public void onDestroy() {

        super.onDestroy();
      //  mySQLiteAdapter.deleteAll();
        Log.e("Service Destroy", "Successful");


    }*/

    private void DataSender()
    {
        //timer.cancel();

        List<NameValuePair> contacts=new ArrayList<NameValuePair>();

        contacts=mySQLiteAdapter.getAllContacts();

         String url="http://10.0.2.2:3325/Product/Create?"; 

         int response = 0;

            try 
            {
                response = CustomHttpClient.executeHttpPost(url, contacts);

                if(response==200)
                {
                    Log.e("Data Sent", "Response 200");
                }

                else{

                    Log.e("Service Data", "Faield to upload data" );
                }

            }
            catch (Exception e)
            {
                Log.e("Data Sending", e.toString());
                e.printStackTrace();
            }
    }

}

SQLiteAdapter.java

package com.remote.synchronizer.haris;

import java.util.ArrayList;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

public class SQLiteAdapter extends SQLiteOpenHelper {

    public static final String DATABASE_NAME = "Product";
    public static final String TABLE_NAME = "Orders";
    public static final int DATABASE_VERSION = 1;
    public static final String KEY_ID = " _id";  //
    public static final String KEY_NAME = "name";
    public static final String KEY_SHOP = "shop";
    private static final String KEY_CITY = "city";
    private static final String KEY_DATE = "datee";
    private static final String KEY_ORDER = "orderr";


    private static final String CREATE_TABLE =
        "CREATE TABLE " + TABLE_NAME + " ("
        + KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
        + KEY_NAME + " VARCHAR,"
        + KEY_SHOP + " VARCHAR," + KEY_CITY + " VARCHAR, " + KEY_DATE + " VARCHAR, " + KEY_ORDER + " VARCHAR" +");";


    public SQLiteAdapter(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);  
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(CREATE_TABLE);   
    }

    private SQLiteDatabase sqLiteDatabase;
    private SQLiteAdapter sqLiteHelper=this;

    public void close(){
        sqLiteHelper.close();
    }

    public void insert(String name, String shop, String city, String datee, String orderr){

        try
        {
        ContentValues contentValues = new ContentValues();
        contentValues.put(KEY_NAME, name);
        contentValues.put(KEY_SHOP, shop);
        contentValues.put(KEY_CITY, city);
        contentValues.put(KEY_DATE, datee);
        contentValues.put(KEY_ORDER, orderr);
        sqLiteDatabase.insertOrThrow(TABLE_NAME, KEY_ID, contentValues);
        //sqLiteDatabase.close();
        }
        catch(Exception e)
        {
            e.printStackTrace();
            Log.e("Insertion", e.toString());

            }
    }

    public void deleteAll(){
         sqLiteDatabase.delete(TABLE_NAME, null, null);
    }

    public void delete_byID(int id){
        sqLiteDatabase.delete(TABLE_NAME, KEY_ID+"="+id, null);
    }

    /*public Cursor queueAll(){
        String[] columns = new String[]{KEY_ID, KEY_NAME, KEY_SHOP, KEY_CITY,  KEY_DATE, KEY_ORDER};
        Cursor cursor = sqLiteDatabase.query(TABLE_NAME, columns, 
                null, null, null, null, null);

        return cursor;
    }*/

    public List<NameValuePair> getAllContacts() {
        List<NameValuePair> postParameters = new ArrayList<NameValuePair>();

        String selectQuery = "SELECT  * FROM " + TABLE_NAME;
        sqLiteHelper.getReadableDatabase();
        Cursor cursor = sqLiteDatabase.rawQuery(selectQuery, null);

        if(cursor.moveToFirst()){
            while(!cursor.isAfterLast())
            {
                postParameters.add(new BasicNameValuePair("User", cursor.getString(cursor.getColumnIndex(KEY_NAME))));
                postParameters.add(new BasicNameValuePair("ShopName", cursor.getString(cursor.getColumnIndex(KEY_SHOP))));
                postParameters.add(new BasicNameValuePair("city", cursor.getString(cursor.getColumnIndex(KEY_CITY))));
                postParameters.add(new BasicNameValuePair("OrderDate", cursor.getString(cursor.getColumnIndex(KEY_DATE))));
                postParameters.add(new BasicNameValuePair("OrderDetail", cursor.getString(cursor.getColumnIndex(KEY_ORDER))));
                cursor.moveToNext();
            }

        }
        //cursor.close();
        return postParameters;
    };



    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        Log.w(SQLiteAdapter.class.getName(),
                "Upgrading database from version " + oldVersion + " to "
                    + newVersion + ", which will destroy all old data");
            db.execSQL("DROP TABLE IF EXISTS " + CREATE_TABLE);
            onCreate(db);
    }

}

Thanks in Advance

Answer 1

You never initialize sqLiteDatabase in your SQLiteAdapter class.

Change your onCreate method to this:

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL(CREATE_TABLE);
    sqLiteDatabase = db;
}