protected boolean clearMetricsHeaders(Message in) {
        return in.removeHeaders(HEADER_PATTERN);
    }
@Test
    public void testClearMetricsHeaders() {
        when(in.removeHeaders(HEADER_PATTERN)).thenReturn(true);
        assertThat(okProducer.clearMetricsHeaders(in), is(true));
        inOrder.verify(in, times(1)).removeHeaders(HEADER_PATTERN);
        inOrder.verifyNoMoreInteractions();
    }