diff --git a/htrace-core/src/main/java/org/apache/htrace/SamplerBuilder.java b/htrace-core/src/main/java/org/apache/htrace/SamplerBuilder.java index 5d90e48..ed7e9b6 100644 --- a/htrace-core/src/main/java/org/apache/htrace/SamplerBuilder.java +++ b/htrace-core/src/main/java/org/apache/htrace/SamplerBuilder.java @@ -45,7 +45,7 @@ public class SamplerBuilder { public Sampler build() { String str = conf.get(SAMPLER_CONF_KEY); - if (str.isEmpty()) { + if (str == null || str.isEmpty()) { return NeverSampler.INSTANCE; } if (!str.contains(".")) { diff --git a/htrace-core/src/test/java/org/apache/htrace/TestSampler.java b/htrace-core/src/test/java/org/apache/htrace/TestSampler.java index 31060d4..0cc7d97 100644 --- a/htrace-core/src/test/java/org/apache/htrace/TestSampler.java +++ b/htrace-core/src/test/java/org/apache/htrace/TestSampler.java @@ -44,6 +44,11 @@ public class TestSampler { fromKeyValuePairs("sampler", "NonExistentSampler")). build(); Assert.assertEquals(NeverSampler.class, neverSampler2.getClass()); + + Sampler neverSampler3 = new SamplerBuilder(HTraceConfiguration. + fromKeyValuePairs("sampler.is.not.defined", "NonExistentSampler")). + build(); + Assert.assertEquals(NeverSampler.class, neverSampler3.getClass()); } @Test