some databse operations on android

database.java

package com.example.databaseproject;

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.SQLiteOpenHelper;

public class ShirshakDatabaseAdapter {
    ShirshakHelper helper;
    public ShirshakDatabaseAdapter(Context context){
        helper = new ShirshakHelper(context);
    }
    public long insertData(String name,String password){
        SQLiteDatabase db  = helper.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(ShirshakHelper.NAME,name);
        contentValues.put(ShirshakHelper.PASSWORD,password);
        long id=db.insert(ShirshakHelper.TABLE_NAME,null,contentValues);
        db.close();
        return id;
    }
    public String getAllData(){
        StringBuffer buffer = new StringBuffer();
        SQLiteDatabase db = helper.getWritableDatabase();
        String[] columns={ShirshakHelper.UID,ShirshakHelper.NAME,ShirshakHelper.PASSWORD};
        Cursor cursor=db.query(ShirshakHelper.TABLE_NAME,columns,null,null,null,null,null);
        while(cursor.moveToNext()) {
            int index1 = cursor.getColumnIndex(ShirshakHelper.UID);
            int id = cursor.getInt(index1);
            int index2 = cursor.getColumnIndex(ShirshakHelper.NAME);
            String name = cursor.getString(index2);
            int index3 = cursor.getColumnIndex(ShirshakHelper.PASSWORD);
            String password = cursor.getString(index3);
            buffer.append(id+" "+name+" "+password+"\n");
        }
        return buffer.toString();
    }
    public String getData(String name){

        StringBuffer buffer = new StringBuffer();
        SQLiteDatabase db = helper.getWritableDatabase();
        String[] columns={ShirshakHelper.NAME,ShirshakHelper.PASSWORD};
        Cursor cursor=db.query(ShirshakHelper.TABLE_NAME,columns,ShirshakHelper.NAME+" = '"+name+"' ",null,null,null,null);
        while(cursor.moveToNext()) {
            int index4 = cursor.getColumnIndex(ShirshakHelper.NAME);
            String personName = cursor.getString(index4);
            int index5 = cursor.getColumnIndex(ShirshakHelper.PASSWORD);
            String password = cursor.getString(index5);
            buffer.append(name+" "+password+"\n");
        }
        return buffer.toString();
    }
    public int updateName(String oldName,String newName){
        ContentValues content = new ContentValues();
        SQLiteDatabase db = helper.getWritableDatabase();
        content.put(ShirshakHelper.NAME,newName);
        String[] whereArgs={oldName};
       int count= db.update(ShirshakHelper.TABLE_NAME,content,ShirshakHelper.NAME+"=?",whereArgs);
       return count;
    }
    public int deleteName(){
        SQLiteDatabase db = helper.getWritableDatabase();
        String[] whereArgs ={"yug"};
        int count=db.delete(ShirshakHelper.TABLE_NAME,ShirshakHelper.NAME+"=?",whereArgs);
        return count;
    }
    static class ShirshakHelper extends SQLiteOpenHelper{
        private static final String DATABASE_NAME = "shirshakdatabase";
        private static final int DATABASE_VERSION=3; //you should keep updating your version name while making changes on table(ANY CHANGESS)
        private static final String TABLE_NAME="SHIRSHAKTABLE";
        private static final String UID="_id";
        private Context context;
        private static final String NAME="Name";
        private static final String PASSWORD="Password";
        private static final String DROP_TABLE="DROP TABLE IF EXISTS "+TABLE_NAME;
        private static final String CREATE_TABLE="CREATE TABLE "+TABLE_NAME+"("+UID+" INTEGER PRIMARY KEY AUTOINCREMENT,"+NAME+" VARCHAR(255) ,"+PASSWORD+" VARCHAR(255));";
        ShirshakHelper(Context context){
            super(context,DATABASE_NAME,null,DATABASE_VERSION);
            this.context=context;
            Message.message(context,"constructor was called");
        }
        @Override
        public void onCreate(SQLiteDatabase db) {
            try {
                db.execSQL(CREATE_TABLE);
                Message.message(context,"onCreate was called");
            }
            catch(SQLException e){
                Message.message(context,""+e);
            }
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            try{
                Message.message(context,"onUpgrade was called");
                db.execSQL(DROP_TABLE);
                onCreate(db);
            }catch (SQLException e){
                Message.message(context,""+e);
            }
        }
    }
}
////////////////////////////////now mainActivity
package com.example.databaseproject;

import androidx.appcompat.app.AppCompatActivity;

import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    EditText username,password,detail;
    ShirshakDatabaseAdapter databaseAdapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        username=(EditText)findViewById(R.id.usernameText);
        password=(EditText)findViewById(R.id.passwordText);
        detail=(EditText)findViewById(R.id.editText);
       databaseAdapter = new ShirshakDatabaseAdapter(this);
    }
    public void addUser(View v){
        String user = username.getText().toString();
        String pass = password.getText().toString();
        long id=databaseAdapter.insertData(user,pass);
        if(id<0){
            Message.message(this,"Unsuccesfull");
        }
        else{
            Message.message(this,"Successfully inserted a row");
        }
    }
    public void viewDetails(View v){
          String data=databaseAdapter.getAllData();
          Message.message(this,data);
    }
    public void viewUserDetails(View v){
      String text=detail.getText().toString();
      String data=databaseAdapter.getData(text);
      Message.message(this,data);
    }
public void update(View v){
        databaseAdapter.updateName("shirshak","BetelGeuseee");
}
public void delete(View v){
int count=databaseAdapter.deleteName();
Message.message(this,""+count);
}
}