public class Season {
  // 把Season類定義成不可變的，將其成員變量也定義成final的
  private final String name;
  private final String desc;
  public static final Season SPRING
      = new Season("春天", "趁春踏青");
  public static final Season SUMMER
      = new Season("夏天", "夏日炎炎");
  public static final Season FALL
      = new Season("秋天", "秋高氣爽");
  public static final Season WINTER
      = new Season("冬天", "圍爐賞雪");
  public static Season getSeason( int seasonNum ) {
    switch (seasonNum) {
      case 1:
        return SPRING;
      case 2:
        return SUMMER;
      case 3:
        return FALL;
      case 4:
        return WINTER;
      default:
        return null;
    }
  }
  // 將構造器定義成private訪問權限
  private Season( String name, String desc ) {
    this.name = name;
    this.desc = desc;
  }
  // 只為name和desc提供getter方法
  public String getName() {
    return this.name;
  }
  public String getDesc() {
    return this.desc;
  }
}

public class SeasonTest
{
  public SeasonTest(Season s)
  {
   System.out.println(s.getName() +
     "，這真是一個"+ s.getDesc() + "的季節(jié)");
  }
  public static void main(String[] args)
  {
   // 直接使用Season的FALL常量代表一個Season對象
   new SeasonTest(Season.FALL);
  }
}