CustomListing currentListing = new CustomListing();
Intent i = new Intent();
Bundle b = new Bundle();
b.putParcelable(Constants.CUSTOM_LISTING, currentListing);
i.putExtras(b);
i.setClass(this, SearchDetailsActivity.class);
startActivity(i);

Bundle b = this.getIntent().getExtras();
if (b != null)
    mCurrentListing = b.getParcelable(Constants.CUSTOM_LISTING);

class Myclass    {
  int a;
  class SubClass    {
       int b;
  }
}

MyClass src = new MyClass();
Gson gS = new Gson();
String target = gS.toJson(src); // Converts the object to a JSON String

Intent i = new Intent(FromActivity.this, ToActivity.class);
i.putExtra("MyObjectAsString", target);

String target = getIntent().getStringExtra("MyObjectAsString");
MyClass src = gS.fromJson(target, MyClass.class); // Converts the JSON String to an Object

public class PersonHelper
{
    public static Person person;
}