swing - Java GUI programmming -


code gives error of nullpointer exception.....wat do?

import java.awt.event.*; import javax.swing.*;  public class gui implements actionlistener{ jbutton button;  public gui(){     jframe frame=new jframe();     jbutton button =new jbutton("click me!");     button.addactionlistener(this);     frame.setdefaultcloseoperation(jframe.exit_on_close);     frame.getcontentpane().add(button);     frame.setsize(270,300);     frame.setvisible(true); } public static void main(string[] args){     new gui(); }  public void actionperformed(actionevent e){     button.settext("i've been clicked"); }  } 

jbutton button =new jbutton

this creates local variable.
button field still null.


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