Java tutorial
/** * 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.yarn.api.records; import org.apache.hadoop.classification.InterfaceAudience.Public; import org.apache.hadoop.classification.InterfaceStability.Unstable; /** * <p>State of a <code>Node</code>.</p> */ @Public @Unstable public enum NodeState { /** New node */ NEW, /** Running node */ RUNNING, /** Node is unhealthy */ UNHEALTHY, /** Node is out of service */ DECOMMISSIONED, /** Node has not sent a heartbeat for some configured time threshold*/ LOST, /** Node has rebooted */ REBOOTED, /** Node decommission is in progress */ DECOMMISSIONING, /** Node has shutdown gracefully. */ SHUTDOWN; public boolean isUnusable() { return (this == UNHEALTHY || this == DECOMMISSIONED || this == LOST || this == SHUTDOWN); } }