Sampler { public abstract boolean next();  abstract boolean next(); static final Sampler ALWAYS; static final Sampler NEVER; }
@Test public void testAlwaysSampler() { AlwaysSampler sampler = new AlwaysSampler(HTraceConfiguration.EMPTY); Assert.assertTrue(sampler.next()); }
@Test public void testNeverSampler() { NeverSampler sampler = new NeverSampler(HTraceConfiguration.EMPTY); Assert.assertTrue(!sampler.next()); }