Months.java

/* $HeadURL$
 * $Id$ 
 *
 * Copyright (c) 2006-2010 by Public Library of Science
 * http://plos.org
 * http://ambraproject.org
 *
 * 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
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 */
package org.ambraproject.views.article;

import java.util.TreeMap;

/**
 * An ordered list of months (as month numbers, from 1 to 12). Each month has a list of days.
 */
public class Months extends TreeMap<Integer, Days> {
  /**
   * @return the list of days (possibly emtpy, but always non-null)
   */
  public Days getDays(Integer mon) {
    Days days = get(mon);
    if (days == null)
      put(mon, days = new Days());
    return days;
  }
}