Without casting, is there anyother way?

Question

Without inserting the casting at each aPanel,
is there any other way to do this?
package hiding.test;
public class ParentPanel {
     public String aButton;
     public ParentPanel() {
          System.out.println("Hi, parent!");
     public void init() {          
          aButton = new String("aButtonAtParent");
          System.out.println(aButton + "init() Parent");
     public String getAButton() {
          // TODO Auto-generated method stub
          return aButton;
package hiding.test;
public class ChildPanel extends ParentPanel {
     public String aButton;
     public ChildPanel() {
          System.out.println("Hi, Child!");
     public void init() {     
          aButton = new String("aButtonAtChild");
          System.out.println(aButton  + "---init() Child");
     public String getAButton() {
          return aButton + "- child";
package hiding.test;
public class MainTest {
     public static void main(String[] args) {
          ParentPanel aPanel = new ChildPanel();
          aPanel.init();
          //----- Question ???? : -------------------------------------------------
          // without casting like this  ( (ChildPanel) aPanel).aButton)
          // is there any other way to do it???
          System.out.println("===aPanel.aButton =" + ( (ChildPanel) aPanel).aButton);
          System.out.println("===aPanel.getAButton()=" + aPanel.getAButton());     
}null

Answer 1

The reason why is the following, there is one big panel.
I have to change only the one of big panel.
And big panel is shared by each version.
A version -- requires no change.
B version-- requires only the one panel of Big panel needs to be changed.
So, I created createTheOnePanel() method return Parent Panel in BigPanel and when BigPanel is called the first time, I redefine this method so that it returns ChildPanel.
Now, it works aPanel = createTheOnePanel() // returns ChildPanel in BigPanel.java But, aPanel.aButton and all others are null, unless
I put the cast in front of them.
However, I cannot put cast in front of them because the case when
aPanel = createTheOnePanel() ; /// returns ParentPanel.
So, without putting the cast, what do I need to do, I remember I did
create GetXXX() very slightly---