content: /**
   * 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 com.alibaba.jstorm.container.cgroup.core;
  
  import java.io.IOException;
  
  import com.alibaba.jstorm.container.CgroupUtils;
  import com.alibaba.jstorm.container.Constants;
  import com.alibaba.jstorm.container.SubSystemType;
  
  public class FreezerCore implements CgroupCore {
  
      public static final String FREEZER_STATE = "/freezer.state";
  
      private final String dir;
  
      public FreezerCore(String dir) {
          this.dir = dir;
      }
  
      @Override
      public SubSystemType getType() {
          return SubSystemType.freezer;
      }
  
      public void setState(State state) throws IOException {
          CgroupUtils.writeFileByLine(Constants.getDir(this.dir, FREEZER_STATE), state.name().toUpperCase());
      }
  
      public State getState() throws IOException {
          return State.getStateValue(CgroupUtils.readFileByLine(Constants.getDir(this.dir, FREEZER_STATE)).get(0));
      }
  
      public enum State {
          frozen, freezing, thawed;
  
          public static State getStateValue(String state) {
              if (state.equals("FROZEN"))
                  return frozen;
              else if (state.equals("FREEZING"))
                  return freezing;
              else if (state.equals("THAWED"))
                  return thawed;
              else
                  return null;
          }
      }
  
  }
  