FormattedTextField with mixed case characters with DocumentFilter set to uppercase

Question

My problem is as follows:

I have a:

public class WWFormattedTextField extends JFormattedTextField implements FocusListener {

All of the formatted textfields on all the screens will always be uppercase. We want them appear upper case while typing, etc. So here is what we did for that:

public class WWFormattedTextField extends JFormattedTextField implements FocusListener {

private DocumentFilter filter = new UppercaseDocumentFilter();
private boolean isEmail = false;

public WWFormattedTextField() {
    super();
    init();
}

private void init() {
    addFocusListener(this);
    ((AbstractDocument) this.getDocument()).setDocumentFilter(filter);
}
public void setIsEmail(boolean email) {
    //Normally this is where I would put something like
    //if email is true - allow mixed case characters
    this.isEmail = email;
}

public boolean getIsEmail() {
    return isEmail;
}

Now all of the WWFormattedTextFields on all screens are typed in upper case characters. Here is the UppercaseDocumentFilter() mentioned earlier:

public class UppercaseDocumentFilter extends DocumentFilter{
    @Override
    public void insertString(DocumentFilter.FilterBypass fb, int offset, String text, AttributeSet attr) throws BadLocationException {
        fb.insertString(offset, text.toUpperCase(), attr);
    }

    @Override
    public void replace(DocumentFilter.FilterBypass fb, int offset, int length, String text, AttributeSet attrs) throws BadLocationException {
        fb.replace(offset, length, text.toUpperCase(), attrs);
    }
}

As you can see, this FormattedTextField also has an isEmail property. When that value is true - I want to allow user to enter mixed case characters into the field, but only that specific one.

Any hints/suggestions on how I can do that?

Answer 1

Add an isEmail property to UppercaseDocumentFilter so that specific filters can produce uppercase text

public class UppercaseDocumentFilter extends DocumentFilter {

    private boolean isEmail;

    public UppercaseDocumentFilter(boolean isEmail) {
        this.isEmail = isEmail; 
    }

    @Override
    public void insertString(DocumentFilter.FilterBypass fb, int offset, String text, AttributeSet attr) throws BadLocationException {
        fb.insertString(offset, isEmail? text: text.toUpperCase(), attr);
    }

    @Override
    public void replace(DocumentFilter.FilterBypass fb, int offset, int length, String text, AttributeSet attrs) throws BadLocationException {
        fb.replace(offset, length, isEmail? text: text.toUpperCase(), attrs);
    }
}

then set the filter like this

DocumentFilter filter = new UppercaseDocumentFilter(isEmail);
((AbstractDocument) this.getDocument()).setDocumentFilter(filter);