content: /*
   * Copyright (c) 2015.  Airbnb.com
   *
   *  Licensed 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 com.airbnb.metrics;
  
  import com.yammer.metrics.core.Metric;
  import com.yammer.metrics.core.MetricName;
  import com.yammer.metrics.core.MetricPredicate;
  import org.apache.log4j.Logger;
  
  import java.util.regex.Pattern;
  
  /**
   *
   */
  public class ExcludeMetricPredicate implements MetricPredicate {
    private final Logger logger = Logger.getLogger(getClass());
  
    final String excludeRegex;
    final Pattern pattern;
  
    public ExcludeMetricPredicate(String excludeRegex) {
      this.excludeRegex = excludeRegex;
      this.pattern = Pattern.compile(excludeRegex);
    }
  
    @Override
    public boolean matches(MetricName name, Metric metric) {
      String n = MetricNameFormatter.format(name);
      boolean excluded = pattern.matcher(n).matches();
      if (excluded) {
        if (logger.isTraceEnabled()) {
          logger.trace("Metric " + n + " is excluded");
        }
      }
      return !excluded;
    }
  }
  