htrace-core/src/test/java/org/apache/htrace/core/TestNullScope.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.htrace.core;

import org.junit.Assert;
import org.junit.Test;

public class TestNullScope {
  @Test
  public void testNullScope() {
    Assert.assertTrue(!Trace.isTracing());
    TraceScope tc = Trace.startSpan("NullScopeSingleton");
    Assert.assertTrue(tc == NullScope.INSTANCE);
    tc.detach();
    tc.detach(); // should not fail even if called multiple times.
    Assert.assertFalse(tc.isDetached());
    tc.close();
    tc.close(); // should not fail even if called multiple times.
  }
}