src/main/java/org/efaps/ui/wicket/models/field/factories/StringUIFactory.java
@Override
    protected String getReadOnlyValue(final AbstractUIField _uiField)
        throws EFapsException
    {
        Object obj = _uiField.getValue().getReadOnlyValue(_uiField.getParent().getMode());
        if (obj != null && obj instanceof Collection) {
            obj = StringUtils.join(((Collection<?>) obj).iterator(), ", ");
        }
        return obj == null ? "" : String.valueOf(obj);
    }
@Override
    protected String getReadOnlyValue(final AbstractUIField _uiField)
        throws EFapsException
    {
        Object obj = _uiField.getValue().getReadOnlyValue(_uiField.getParent().getMode());
        if (obj != null && obj instanceof Collection) {
            obj = StringUtils.join(((Collection<?>) obj).iterator(), ", ");
        }
        return obj == null ? "" : String.valueOf(obj);
    }
{@inheritDoc}