001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019 package org.apache.hadoop.yarn.api.records;
020
021 import org.apache.hadoop.classification.InterfaceAudience.Private;
022 import org.apache.hadoop.classification.InterfaceAudience.Public;
023 import org.apache.hadoop.classification.InterfaceStability.Stable;
024 import org.apache.hadoop.classification.InterfaceStability.Unstable;
025 import org.apache.hadoop.yarn.util.Records;
026
027 /**
028 * <p><code>YarnClusterMetrics</code> represents cluster metrics.</p>
029 *
030 * <p>Currently only number of <code>NodeManager</code>s is provided.</p>
031 */
032 @Public
033 @Stable
034 public abstract class YarnClusterMetrics {
035
036 @Private
037 @Unstable
038 public static YarnClusterMetrics newInstance(int numNodeManagers) {
039 YarnClusterMetrics metrics = Records.newRecord(YarnClusterMetrics.class);
040 metrics.setNumNodeManagers(numNodeManagers);
041 return metrics;
042 }
043
044 /**
045 * Get the number of <code>NodeManager</code>s in the cluster.
046 * @return number of <code>NodeManager</code>s in the cluster
047 */
048 @Public
049 @Stable
050 public abstract int getNumNodeManagers();
051
052 @Private
053 @Unstable
054 public abstract void setNumNodeManagers(int numNodeManagers);
055
056 }