NullPointerException for JButton
java, jbutton, nullpointerexception, swing
Solution
but= new JButton[4];
This only allocates space for four array elements; each element is initialized to `null`, the default value for a reference type like your `JButton` objects.
`but[0]`, `but[1]`, `but[2]`, `but[3]` are all `null`.
You should initialize them like this:
but[0] = new JButton(); //or whatever.
Problem
I am trying to assign text to buttons inside a loop but I am getting an NullPointerException. I have initialized the button array inside constructor of the class and after initilizatoin, I call the following method. Here is the code where I am getting error. ``` public class Alfred { private String names[]={"nfs","gta","maxpayne","hitman"}; private JButton but[]; public Alfred() { ... but= new JButton[4]; AssignLettersToButtons(); } private void AssignLettersToButtons() { for(int i=0;i<names.length;i++) { but[i].setText(names[i]); // error pane1.add(but[i]); } } } } ``` The length of button array and names array is same. What is the reason for this exception and how can I solve it? Regards