code: /*
   * Copyright © 2014-2017 EntIT Software LLC, a Micro Focus company (L.P.)
   *
   * Licensed 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 io.cloudslang.score.api;
  
  import java.io.Serializable;
  import java.util.ArrayDeque;
  import java.util.Map;
  
  public class StatefulSessionStack implements Serializable {
  
      private static final long serialVersionUID = -7408054784258769720L;
  
      private ArrayDeque<Map<String, StatefulQueueValue>> stack;
  
      public StatefulSessionStack() {
          stack = new ArrayDeque<>();
      }
  
      public void pushSessionsMap(Map<String, StatefulQueueValue> newContext) {
          stack.push(newContext);
      }
  
      public Map<String, StatefulQueueValue> popSessionMap() {
          if (stack.isEmpty()) {
              return null;
          }
          return stack.pop();
      }
  
      public Map<String, StatefulQueueValue> peakSessionMap() {
          return stack.peek();
      }
  
      public boolean isEmpty() {
          return stack.isEmpty();
      }
  
      public int size() {
          return stack.size();
      }
  }
  