public void setPrefix(String prefix) {
        this.prefix = prefix;
    }
@Test
    public void customMetricsPrefix() throws Exception {
        iqtp.setPrefix(PREFIX);
        iqtp.start();

        assertThat(metricRegistry.getNames())
                .overridingErrorMessage("Custom metrics prefix doesn't match")
                .allSatisfy(name -> assertThat(name).startsWith(PREFIX));

        iqtp.stop();
        assertThat(metricRegistry.getMetrics())
                .overridingErrorMessage("The default metrics prefix was changed")
                .isEmpty();
    }