@Override
    public ByteBuf retainedSlice() {
        return slice().retain();
    }
@Test
    public void testRetainedSliceAfterReleaseRetainedSlice() {
        ByteBuf buf = newBuffer(1);
        ByteBuf buf2 = buf.retainedSlice(0, 1);
        assertRetainedSliceFailAfterRelease(buf, buf2);
    }