java - JScrollPane won't display -

i'd create simple gui based 'echo' application ability scroll , down through previous input. far, working except when add jtextpane jscrollpane, lose input , scroll never appears.

can point me in right direction?

here code have far:

import java.awt.*;     import javax.swing.*;  public class filereadergui {     private jframe frame;     private jpanel inputpanel;     private jtextfield userinput;      private jscrollpane scrollpane;     private jtextpane display;     jbutton print;      public void show() {         frame = new jframe();         frame.setsize(400, 200);         frame.setdefaultcloseoperation(jframe.exit_on_close);          buildinputpanel();         builddisplaypanel();         frame.getcontentpane().add(inputpanel, borderlayout.south);         frame.getcontentpane().add(scrollpane, borderlayout.center);          frame.setvisible(true);     }      public void builddisplaypanel() {         display = new jtextpane();             scrollpane = new jscrollpane(display);     }      public void buildinputpanel() {         inputpanel = new jpanel();          userinput = new jtextfield();         userinput.setcolumns(20);         inputpanel.add(userinput);          print = new jbutton("print");         print.addactionlistener(new actionlistener() {             public void actionperformed(actionevent e) {                 string current = display.gettext();                 string input = userinput.gettext();                  string newtext = string.format("%s\n%s", current, input);                 display.settext(newtext);             }         });         inputpanel.add(print);     } } 

and, here caller:

public class filereader {     public void go() {         filereadergui gui = new filereadergui();         gui.show();     }      public static void main(string[] args) {         new filereader().go();     } } 

 i'd should have scrollpane = new jscrollpane(display); 

i agree above.

did reorder code make sure created text pane before creating scrollpane?

    //scrollpane = new jscrollpane();     //display = new jtextpane();     //scrollpane.add(display);      display = new jtextpane();     scrollpane = new jscrollpane(display); 

if doesn't post sscce includes main() method execute code.