How to stop main activity from exiting on pressing theback button

MainActivity.java

package foo.foo.foo.foo;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
    
    /**
      This override here is what makes this android activity goto home, upon pressing the back button.
    */
    @Override
    public void onBackPressed() {
        Intent intent = new Intent(Intent.ACTION_MAIN);
        intent.addCategory(Intent.CATEGORY_HOME);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        startActivity(intent);
    }


    public void onClickTransaction(View view) {
        startActivity(new Intent(MainActivity.this,SwipeCard.class));
    }

    public void onClickSalesReport(View view) {

    }
}