hadoop MutableMetricsFactory 源码

haddop MutableMetricsFactory 代码

文件路径：/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/metrics2/lib/MutableMetricsFactory.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.hadoop.metrics2.lib;

import java.lang.reflect.Field;
import java.lang.reflect.Method;

import org.apache.commons.lang3.StringUtils;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.metrics2.MetricsException;
import org.apache.hadoop.metrics2.MetricsInfo;
import org.apache.hadoop.metrics2.annotation.Metric;
import org.apache.hadoop.metrics2.annotation.Metrics;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@InterfaceAudience.Private
@InterfaceStability.Evolving
public class MutableMetricsFactory {
  private static final Logger LOG =
      LoggerFactory.getLogger(MutableMetricsFactory.class);

  MutableMetric newForField(Field field, Metric annotation,
                            MetricsRegistry registry) {
    if (LOG.isDebugEnabled()) {
      LOG.debug("field "+ field +" with annotation "+ annotation);
    }
    MetricsInfo info = getInfo(annotation, field);
    MutableMetric metric = newForField(field, annotation);
    if (metric != null) {
      registry.add(info.name(), metric);
      return metric;
    }
    final Class<?> cls = field.getType();
    if (cls == MutableCounterInt.class) {
      return registry.newCounter(info, 0);
    }
    if (cls == MutableCounterLong.class) {
      return registry.newCounter(info, 0L);
    }
    if (cls == MutableGaugeInt.class) {
      return registry.newGauge(info, 0);
    }
    if (cls == MutableGaugeLong.class) {
      return registry.newGauge(info, 0L);
    }
    if (cls == MutableGaugeFloat.class) {
      return registry.newGauge(info, 0f);
    }
    if (cls == MutableRate.class) {
      return registry.newRate(info.name(), info.description(),
                              annotation.always());
    }
    if (cls == MutableRates.class) {
      return new MutableRates(registry);
    }
    if (cls == MutableRatesWithAggregation.class) {
      return registry.newRatesWithAggregation(info.name());
    }
    if (cls == MutableStat.class) {
      return registry.newStat(info.name(), info.description(),
                              annotation.sampleName(), annotation.valueName(),
                              annotation.always());
    }
    if (cls == MutableRollingAverages.class) {
      return registry.newMutableRollingAverages(info.name(),
          annotation.valueName());
    }
    if (cls == MutableQuantiles.class) {
      return registry.newQuantiles(info.name(), annotation.about(),
          annotation.sampleName(), annotation.valueName(), annotation.interval());
    }
    throw new MetricsException("Unsupported metric field "+ field.getName() +
                               " of type "+ field.getType().getName());
  }

  MutableMetric newForMethod(Object source, Method method, Metric annotation,
                             MetricsRegistry registry) {
    if (LOG.isDebugEnabled()) {
      LOG.debug("method "+ method +" with annotation "+ annotation);
    }
    MetricsInfo info = getInfo(annotation, method);
    MutableMetric metric = newForMethod(source, method, annotation);
    metric = metric != null ? metric :
        new MethodMetric(source, method, info, annotation.type());
    registry.add(info.name(), metric);
    return metric;
  }

  /**
   * Override to handle custom mutable metrics for fields
   * @param field of the metric
   * @param annotation  of the field
   * @return a new metric object or null
   */
  protected MutableMetric newForField(Field field, Metric annotation) {
    return null;
  }

  /**
   * Override to handle custom mutable metrics for methods
   * @param source the metrics source object
   * @param method to return the metric
   * @param annotation of the method
   * @return a new metric object or null
   */
  protected MutableMetric newForMethod(Object source, Method method,
                                       Metric annotation) {
    return null;
  }

  protected MetricsInfo getInfo(Metric annotation, Field field) {
    return getInfo(annotation, getName(field));
  }

  protected String getName(Field field) {
    return StringUtils.capitalize(field.getName());
  }

  protected MetricsInfo getInfo(Metric annotation, Method method) {
    return getInfo(annotation, getName(method));
  }

  protected MetricsInfo getInfo(Class<?> cls, Metrics annotation) {
    String name = annotation.name();
    String about = annotation.about();
    String name2 = name.isEmpty() ? cls.getSimpleName() : name;
    return Interns.info(name2, about.isEmpty() ? name2 : about);
  }

  /**
   * @return Remove the prefix "get", if any, from the method name. Return the
   * capacitalized method name."
   *
   * @param method input method.
   */
  protected String getName(Method method) {
    String methodName = method.getName();
    if (methodName.startsWith("get")) {
      return StringUtils.capitalize(methodName.substring(3));
    }
    return StringUtils.capitalize(methodName);
  }

  protected MetricsInfo getInfo(Metric annotation, String defaultName) {
    String[] value = annotation.value();
    if (value.length == 2) {
      // Use name and description from the annotation
      return Interns.info(value[0], value[1]);
    }
    if (value.length == 1) {
      // Use description from the annotation and method name as metric name
      return Interns.info(defaultName, value[0]);
    }
    // Use method name as metric name and description
    return Interns.info(defaultName, defaultName);
  }
}

相关信息

hadoop 源码目录

相关文章

hadoop DefaultMetricsFactory 源码

hadoop DefaultMetricsSystem 源码

hadoop Interns 源码

hadoop MethodMetric 源码

hadoop MetricsAnnotations 源码

hadoop MetricsInfoImpl 源码

hadoop MetricsRegistry 源码

hadoop MetricsSourceBuilder 源码

hadoop MutableCounter 源码

hadoop MutableCounterInt 源码