public BooleanFieldPropertyWriter(BeanPropertyWriter src, BeanPropertyAccessor acc, int index,
            JsonSerializer<Object> ser) {
        super(src, acc, index, ser);

        if (MARKER_FOR_EMPTY == _suppressableValue) {
            _suppressableBoolean = false;
            _suppressableSet = true;
        } else if (_suppressableValue instanceof Boolean) {
           ...
        }

    public final void serializeAsElement(Object bean, JsonGenerator gen, SerializerProvider prov) throws Exception
    { 
        ...
        if (!_suppressableSet || _suppressableBoolean != value) {
            gen.writeBoolean(value);
        } else { 
           ...
        }
    }