database imp things

MAIN DATABASE HANDLER CREATION

package com.example.viraj.grocery_list.Data;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import com.example.viraj.grocery_list.Model.Grocery;
import com.example.viraj.grocery_list.Util.Constants;

import java.net.PortUnreachableException;
import java.util.List;

public class DatabaseHandler extends SQLiteOpenHelper {
    private Context ctx;

    public DatabaseHandler(Context context) {
        super(context, Constants.DB_NAME, null, Constants.DB_VERSION);
        this.ctx = context;
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String CREATE_GROCERY_TABLE = "CREATE TABLE " + Constants.TABLE_NAME + "("
                + Constants.KEY_ID + "INTEGER PRIMARY KEY,"
                + Constants.KEY_GROCERY_ITEM + "TEXT,"
                + Constants.KEY_QTY_NUMBER + "TEXT,"
                + Constants.KEY_DATE_NAME + "LONG);";
        db.execSQL(CREATE_GROCERY_TABLE);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS" + Constants.TABLE_NAME);
        onCreate(db);
    }
    //---------------CRUD OPERATION CREATE READ UPDATE DELETE
//===========GROCERY CLASS KO IMPORT KIYA   ADD GROCERY
    public void  AddGrocery(Grocery grocery)
    {

    }
    //==========================GET A GROCERY
    private Grocery getgrocery(int id)
    {
return null;
    }
    //==========================GET A-L-L GROCERIES
    public List<Grocery> getAllGroceries()
    {
        return null;
    }
//========================= UPDATE GROCRIES
    public int updateGrocery(Grocery grocery)
    {
        return 0;
    }
    //=========================DELETE GROCERY
    public void deleteGrocery(int id)
    {

    }
    //=========================get count
    public int getGroceriesCount()
    {
        return 0;
    }
}

MAIN CONSTANTS

package com.example.viraj.grocery_list.Util;

import java.net.PortUnreachableException;

public class Constants {

    //table creation

    public static final int DB_VERSION = 1;

    public static final String DB_NAME = "groceryListDB";

    public static final String TABLE_NAME = "groceryTBL";

    //TABLE COLOUMS

public static final String KEY_ID="id";

public static final String KEY_GROCERY_ITEM="grocery_item";

public static final String KEY_QTY_NUMBER="quantity_number";

public static final String KEY_DATE_NAME="date_added";

}

MAIN MODEL  

package com.example.viraj.grocery_list.Model;

public class Grocery {

    private String name;

    private String quantity;

    private String dateItemAdded;

    private int id;

    //firstgrocery class ka object kiya he

    //second constructor

   // third getter and setter method

//empty constructor

    public Grocery() {

    }

    public Grocery(String name, String quantity, String dateItemAdded, int id) {

        this.name = name;

        this.quantity = quantity;

        this.dateItemAdded = dateItemAdded;

        this.id = id;

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public String getQuantity() {

        return quantity;

    }

    public void setQuantity(String quantity) {

        this.quantity = quantity;

    }

    public String getDateItemAdded() {

        return dateItemAdded;

    }

    public void setDateItemAdded(String dateItemAdded) {

        this.dateItemAdded = dateItemAdded;

    }

    public int getId() {

        return id;

    }

    public void setId(int id) {

        this.id = id;

    }

}