将textfield输入限制为列数/与DocumentFilter冲突

Question

我有一个WWFormattedTextField：

public class WWFormattedTextField extends JFormattedTextField implements FocusListener {

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

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

private void init() {
    addFocusListener(this);
//This line makes ALL text in ALL textfields uppercase as they type
    ((AbstractDocument) this.getDocument()).setDocumentFilter(filter);
}

//This method uses value of colulmn property of textfield and creates a mask
//that limits the amount of characters
public void setLimitToMaxInput(boolean limitToMaxInput) {
    int columns = getColumns();
    String patternLimit = "";
    while (columns > 0) {
        patternLimit = patternLimit.concat("*");
        columns -= 1;
    }
    try {
        setFormatterFactory(new javax.swing.text.DefaultFormatterFactory(new javax.swing.text.MaskFormatter(patternLimit)));
    } catch (ParseException ex) {
        Logger.getLogger(WWFormattedTextField.class.getName()).log(Level.SEVERE, null, ex);
    }
    this.limitToMaxInput = limitToMaxInput;
}

我的问题是setLimitToMaxInput覆盖了UppercaseDocumentFilter。该字段仅限于列数，但由于掩码为*-当用户键入时，它不会大写.

需要一些有用的提示或建议来实现我的目标:一个总是大写的文本字段，当达到最大值(列)时限制(停止)用户输入。

UppercaseDocumentFilter的代码：

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);
    }
}

Answer 1

我在看了this post之后才知道的

显然，我不必费心于那种笨重的面具，只需同时使用DocumentFilter :大写和限制输入。