htrace-core/src/main/java/org/apache/htrace/impl/TrueIfTracingSampler.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.impl;

import org.apache.htrace.HTraceConfiguration;
import org.apache.htrace.Sampler;
import org.apache.htrace.Trace;

/**
 * A Sampler that returns true if and only if tracing is enabled for the current thread.
 */
public class TrueIfTracingSampler implements Sampler<Object> {

  public static final TrueIfTracingSampler INSTANCE =
    new TrueIfTracingSampler(null);

  public TrueIfTracingSampler(HTraceConfiguration conf) {
  }

  @Override
  public boolean next(Object info) {
    return Trace.isTracing();
  }

}