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Groups > comp.lang.java.programmer > #15220

Re: It doesn't like 'super' where ever I put it.

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In article <5d496e1f-37e1-43d2-a54c-47dacd3c3fec@googlegroups.com>,
 Lew <lewbloch@gmail.com> wrote:

> Stefan Ram wrote:
> > Eric Sosman writes:
> > >Constructor must call super() or this() before return in
> > >method CalcFrame1.<init>()V [...] (...)
> > >at hand, and the compiler has no way to know which was intended. 
> > 
> >   But the above is not a compiler message, but a run-time message.
> 
> Perhaps there was a transcription error in the OP's message when they put 
> together their otherwise quite serviceable SSCCE.
> 
> >   For a similar situation, I get a compiler message:
> > 
> > |Main.java:31: error: call to super must be first statement in constructor
> > |public void test(){ super(); }
> > 
> >   . (This message does not actually claim that »test« was a
> >   constructor, although one might read it this way.)
> 
> Has anyone tried compiling the OP's first example? (I haven't, and 
> won't.) Perhaps there's a further anomaly in there.

bilsch: Summarizing several insightful answers, "Constructor 
declarations look like method declarations—except that they use the 
name of the class and have no return type [1]."

In addition to reviewing "Initial Threads" [2], also critically examine 
your decision to extend JFrame. It may be more convenient to add a 
JPanel containing buttons, as suggested in KeyPadPanel [3].

SSCCE:

import java.awt.EventQueue;
import javax.swing.JButton;
import javax.swing.JFrame;

public class CalcFrame extends JFrame {

    public /* void */ CalcFrame() {
        super("CalcFrame");
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        add(new JButton("Button"));
        pack();
        setLocationRelativeTo(null);
        setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                CalcFrame cf = new CalcFrame();
            }
        });
    }
}

[1] <http://docs.oracle.com/javase/tutorial/java/javaOO/constructors.html>
[2] <http://download.oracle.com/javase/tutorial/uiswing/concurrency/initial.html>
[3] <https://sites.google.com/site/drjohnbmatthews/keypad-panel>

-- 
John B. Matthews
trashgod at gmail dot com
<http://sites.google.com/site/drjohnbmatthews>

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It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-10 06:27 -0700
  Re: It doesn't like 'super' where ever I put it. v_borchert@despammed.com (Volker Borchert) - 2012-06-10 13:49 +0000
    Re: It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-10 07:08 -0700
      Re: It doesn't like 'super' where ever I put it. Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-10 11:34 -0400
        Re: It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-10 12:58 -0700
          Re: It doesn't like 'super' where ever I put it. markspace <-@.> - 2012-06-10 13:43 -0700
            Re: It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-11 21:01 -0700
      Re: It doesn't like 'super' where ever I put it. v_borchert@despammed.com (Volker Borchert) - 2012-06-10 15:44 +0000
    Re: It doesn't like 'super' where ever I put it. Robert Klemme <shortcutter@googlemail.com> - 2012-06-10 20:39 +0200
      Re: It doesn't like 'super' where ever I put it. "Gavino" <invalid@invalid.invalid> - 2012-06-11 20:13 +0200
        Re: It doesn't like 'super' where ever I put it. Robert Klemme <shortcutter@googlemail.com> - 2012-06-11 22:51 +0200
          Re: It doesn't like 'super' where ever I put it. "Gavino" <invalid@invalid.invalid> - 2012-06-12 00:45 +0200
            Re: It doesn't like 'super' where ever I put it. Martin Gregorie <martin@address-in-sig.invalid> - 2012-06-11 22:53 +0000
              Re: It doesn't like 'super' where ever I put it. Lew <lewbloch@gmail.com> - 2012-06-11 16:42 -0700
            Re: It doesn't like 'super' where ever I put it. Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-11 19:53 -0400
              Re: It doesn't like 'super' where ever I put it. Lew <lewbloch@gmail.com> - 2012-06-11 17:38 -0700
                Re: It doesn't like 'super' where ever I put it. "John B. Matthews" <nospam@nospam.invalid> - 2012-06-11 23:14 -0400
                Re: It doesn't like 'super' where ever I put it. Robert Klemme <shortcutter@googlemail.com> - 2012-06-12 18:21 +0200
      Re: It doesn't like 'super' where ever I put it. Robert Klemme <shortcutter@googlemail.com> - 2012-06-11 22:50 +0200
  Re: It doesn't like 'super' where ever I put it. Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-10 09:59 -0400
  Re: It doesn't like 'super' where ever I put it. Jim Janney <jjanney@shell.xmission.com> - 2012-06-10 08:02 -0600
    Re: It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-10 07:20 -0700
      Re: It doesn't like 'super' where ever I put it. Leif Roar Moldskred <leifm@dimnakorr.com> - 2012-06-10 09:49 -0500
        Re: It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-10 13:15 -0700
      Re: It doesn't like 'super' where ever I put it. Jim Janney <jjanney@shell.xmission.com> - 2012-06-10 10:26 -0600
        Re: It doesn't like 'super' where ever I put it. Jim Janney <jjanney@shell.xmission.com> - 2012-06-10 11:24 -0600
        Re: It doesn't like 'super' where ever I put it. Jim Janney <jjanney@shell.xmission.com> - 2012-06-10 11:38 -0600
          Re: It doesn't like 'super' where ever I put it. v_borchert@despammed.com (Volker Borchert) - 2012-06-10 18:17 +0000
            Re: It doesn't like 'super' where ever I put it. Lew <noone@lewscanon.com> - 2012-06-10 12:26 -0700
        Re: It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-10 13:17 -0700
  Re: It doesn't like 'super' where ever I put it. Roedy Green <see_website@mindprod.com.invalid> - 2012-06-10 11:54 -0700
    Re: It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-10 13:24 -0700
  Re: It doesn't like 'super' where ever I put it. Lew <noone@lewscanon.com> - 2012-06-10 13:56 -0700
    Re: It doesn't like 'super' where ever I put it. bilsch <bilsch01@gmail.com> - 2012-06-11 20:55 -0700
  Re: It doesn't like 'super' where ever I put it. Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-06-11 16:41 -0700

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