AquaSpinnerUI.java 文件源码

/**
 * Returns the calendarField under the start of the selection, or -1 if
 * there is no valid calendar field under the selection (or the spinner
 * isn't editing dates.
 */
private int getCalendarField(final JSpinner spinnerComponent) {
    final JComponent editor = spinnerComponent.getEditor();
    if (!(editor instanceof JSpinner.DateEditor)) {
        return -1;
    }

    final JSpinner.DateEditor dateEditor = (JSpinner.DateEditor) editor;
    final JFormattedTextField ftf = dateEditor.getTextField();
    final int start = ftf.getSelectionStart();
    final JFormattedTextField.AbstractFormatter formatter = ftf.getFormatter();
    if (!(formatter instanceof InternationalFormatter)) {
        return -1;
    }

    final Format.Field[] fields = ((InternationalFormatter) formatter).getFields(start);
    for (final Field element : fields) {
        if (!(element instanceof DateFormat.Field)) {
            continue;
        }
        int calendarField;

        if (element == DateFormat.Field.HOUR1) {
            calendarField = Calendar.HOUR;
        } else {
            calendarField = ((DateFormat.Field) element).getCalendarField();
        }

        if (calendarField != -1) {
            return calendarField;
        }
    }
    return -1;
}