Faulty input gets validated as faulty, but behaves as if it's correct

Question

I have a few components which I want to check whether or not they are filled in. My code iterates over every component added to a list, casts it to the correct type, invokes the getText method and checks whether or not it's empty. In case it's empty, a boolean is set to false and returned. Depending on the boolean, "Yay" (success) or "Nay" (failed) is being shown. As additional testing I have also printed component.toString() each time it failed.

The problem right now is this: every component.toString() method is called in a situation where every component has text. Regardless of my input, the boolean remains success (even when some fields have no text in them).

During debugging I've found that none of my components have a field 'Text' or 'getText' or similar in my debugging window (Eclipse), which might be an indication of the problem.

I can't find the problem, can someone point me to it?

boolean success = checkInput();
if (success) {
    System.out.println("Yay");
} else {
    System.out.println("Nay");
}

checkInput method

private boolean checkInput() {


    boolean success = true;
    List<Component> components = new ArrayList<Component>();
    components.add(txtLeertrajectCode);
    components.add(txtLeertrajectTitel);
    components.add(txtOmschrijving);
    components.add(txtDoelgroep);


    for (Component comp : components) {
            if (comp instanceof JTextField) {
                String curr = ((JTextField) comp).getText().trim();
                if ("".equals(curr)) {
                    System.out.println(comp.toString());
                    comp.setForeground(Color.RED);
                    success = false;
                } else {
                    comp.setForeground(Color.BLACK);
                }
            } else if (comp instanceof JTextArea) {
                String curr = ((JTextArea) comp).getText();
                if ("".equals(curr)) {
                    System.out.println(comp.toString());
                    comp.setForeground(Color.RED);
                    success = false;
                } else {
                    comp.setForeground(Color.BLACK);
                }
            }

        }

        return success;
    }
}

Output:

javax.swing.JTextField[...] 
javax.swing.JTextField[...]
javax.swing.JTextArea[...] 
javax.swing.JTextField[...] 
Yay

EDIT:

Problem solved, appearantly I had my textfields twice, but under a similar name in the file. Obviously the checking was done on the textfields not in use. Silly problem.

How would we have been able to guess at the problem given the information originally posted? Voting to close as too localized. This question will not likely help anyone in the future. — Hovercraft Full Of Eels, Feb 24 '13 at 18:03
this is job for DocumentListener / DocumentFilter with InputMask — mKorbel, Feb 24 '13 at 18:10
@mKorbel: is of course right on the money and has looked at the bigger picture. Your complete approach can be greatly improved by following his suggestion. — Hovercraft Full Of Eels, Feb 24 '13 at 18:15

score 2 · Accepted Answer · answered Feb 24 '13 at 17:30

2

Probably you should change this:

} else {
    System.out.println("Yay");
}

to

} else {
    System.out.println("Nay");
}

answered Feb 24 '13 at 17:30

Mikhail Vladimirov

13,572
1
38
40

You're right, that was a typo. Problem remains though, my correct input is validated as wrong. – Jeroen Vannevel Feb 24 '13 at 17:32
@JeroenVannevel: Please at least up-vote the answer for catching your typo. – Hovercraft Full Of Eels Feb 24 '13 at 17:40

Aliaksei Bulhak · Answer 2 · 2013-02-24T17:41:49.267

0

I think everything all right. You have JTextFiled but it is not containing text (it is simply empty)

UPDATE

I write simple example
results = new JTextArea();
        System.out.println("First :" + results.getText());
        results.setText("Test");
        System.out.println("Second :" + results.getText());

and outpur look like this:

First :
Second :Test

so may be you insert values into textfields after check???

edited Feb 24 '13 at 17:41

answered Feb 24 '13 at 17:30

Aliaksei Bulhak

6,078
8
45
75

I type some random characters each time I test this, all 3 textfields and 1 textarea contain text. – Jeroen Vannevel Feb 24 '13 at 17:33
@JeroenVannevel Could you print `curr` value along with `comp.toString()`? – Mikhail Vladimirov Feb 24 '13 at 17:35
When printing `curr` I receive blank lines, definitely indicating `curr` is an empty value. When I place `System.out.println(txtLeertrajectCode.getText());` in front of the loop, I get another empty value. For some reason all textfields are considered empty. – Jeroen Vannevel Feb 24 '13 at 17:37
@JeroenVannevel look update – Aliaksei Bulhak Feb 24 '13 at 17:42
My `checkInput` method is called when the user clicks a button, so the checking won't be called untill after I fill everything in. – Jeroen Vannevel Feb 24 '13 at 17:44

Faulty input gets validated as faulty, but behaves as if it's correct

2 Answers2