why I'm getting NullPointerException

Question

this is my code and when I run this example it gives NullPointerException could you help me please to find the error or why I've got this exception ! my code :

public class Frame extends JFrame
{
    public Frame()
    {
        JLabel label;
        label.setText("test");
        add(label);
        setSize(200,200);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    }
    public static void main(String[] args) 
    {
        new Frame().setVisible(true);
    }
}

See also http://stackoverflow.com/questions/3988788/what-is-a-stack-trace-and-how-can-i-use-it-to-debug-my-application-errors — Alexis C., Jan 04 '15 at 12:58

score 1 · Answer 1 · answered Jan 04 '15 at 12:57

1

You declare a JLabel variable :

    JLabel label;

And you access it without initializing it first :

    label.setText("test");

You must initialize a variable before accessing it :

    JLabel label = new JLabel ();
    label.setText("test");

answered Jan 04 '15 at 12:57

Eran

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score 0 · Answer 2 · answered Jan 04 '15 at 12:58

0

You have not initialized label;

answered Jan 04 '15 at 12:58

dnsh

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why I'm getting NullPointerException

2 Answers2