tajo-core/src/main/java/org/apache/tajo/master/rm/NodeState.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.tajo.master.rm;

/**
 * It presents the states of {@link NodeStatus}.
 */
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;

  @SuppressWarnings("unused")
  public boolean isUnusable() {
    return (this == UNHEALTHY || this == DECOMMISSIONED || this == LOST);
  }
}