Scala 趣题 9 循环依赖

这道题真是有意思！JVM能否意识到循环依赖呢？当遇到循环依赖时，JVM的处理策略是什么呢？

  object XY {
    object X {
      val value: Int = Y.value + 1
    }
    
    object Y {
      val value: Int = X.value + 1
    }
  }
  
  println(if (math.random > 0.5) XY.X.value else XY.Y.value)

解释：

第一次access 一个object,会触发初始化对象的过程。

如果先调用了X, 初始化X的过程又触发了初始化Y，初始化Y的过程有要依赖X的值，此时VM意思到X正在被初始化，所以返回默认值给Y的初始化程序，Int的默认值为0

时间： 2024-11-10 18:04:54

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