| /** |
| * 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; |
| |
| import com.google.common.base.Objects; |
| import static com.google.common.base.Preconditions.*; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| /** |
| * The immutable metric |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Evolving |
| public abstract class AbstractMetric implements MetricsInfo { |
| private final MetricsInfo info; |
| |
| /** |
| * Construct the metric |
| * @param info about the metric |
| */ |
| protected AbstractMetric(MetricsInfo info) { |
| this.info = checkNotNull(info, "metric info"); |
| } |
| |
| @Override public String name() { |
| return info.name(); |
| } |
| |
| @Override public String description() { |
| return info.description(); |
| } |
| |
| protected MetricsInfo info() { |
| return info; |
| } |
| |
| /** |
| * Get the value of the metric |
| * @return the value of the metric |
| */ |
| public abstract Number value(); |
| |
| /** |
| * Get the type of the metric |
| * @return the type of the metric |
| */ |
| public abstract MetricType type(); |
| |
| /** |
| * Accept a visitor interface |
| * @param visitor of the metric |
| */ |
| public abstract void visit(MetricsVisitor visitor); |
| |
| @Override public boolean equals(Object obj) { |
| if (obj instanceof AbstractMetric) { |
| final AbstractMetric other = (AbstractMetric) obj; |
| return Objects.equal(info, other.info()) && |
| Objects.equal(value(), other.value()); |
| } |
| return false; |
| } |
| |
| @Override public int hashCode() { |
| return Objects.hashCode(info, value()); |
| } |
| |
| @Override public String toString() { |
| return Objects.toStringHelper(this) |
| .add("info", info) |
| .add("value", value()) |
| .toString(); |
| } |
| } |