dynamicArrayAppending

package dynamicList;
import java.util.ArrayList;
public class listAppend {
    protected String username;
    protected String password;
    public listAppend(String username, String password) {
        username = this.username;
        password  = this.password;
        //My goal was to use append the password parameter of every object created, but null kept coming back as value.
        //usernameList.add(this.password);

    }
    //Instead I tried invoking method on specific objects statically after instantiation and it was still null value.
    public void addPass() {
        usernameList.add(this.password);
    }

    static ArrayList<String> usernameList = new ArrayList<String>();
    public String getusername() {
        return username;
    }
    //Just a test to see if password wouldn't print null anymore.
    public void printing() {
        System.out.print(password);
    }

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        //creating object with arguments to be stored as values, right?
        listAppend Kelly = new listAppend("Kelly", "12321");
        System.out.println(Kelly.password);
        Kelly.addPass();
        System.out.println(usernameList);
        //Only going through and assigning it statically seemed to return value as desired.
        //Kelly.password = "920928";


    }

}