Scala对象扩展了Java类静态字段

Bri*_*Hsu 6 java scala

我想知道Scala中Java类的固有静态字段怎么样.

这是一个Java示例,如果我是一个名为ClassFromJava的类,我可以扩展它,添加一些静态字段,并使用子类来访问VERSION字段.

public class ClassFromJava {
    public static int VERSION = 1;
}

public class ClassFromJavaSub extends ClassFromJava {
    public static String NOTE = "A note";
}

public class Test {
    public static void main (String [] args) {
       System.out.println (ClassFromJavaSub.VERSION); // This works.
    }
}
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但是,如果我想在Scala中扩展ClassFromJava,并添加一些常量值,它似乎不起作用.

object ClassFromScala extends ClassFromJava {
    val NOTE = "A Note"
}

object Test {
    def main (args: Array[String]) {
        // This line won't compile
        // ClassFromScala has no value VERSION.
        println (ClassFromScala.VERSION) 
    }
}
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如果我想ClassFromScala也有VERSION变量,我该怎么办?

Rex*_*err 4

object ClassFromScala extends ClassFromJava {
  def VERSION = ClassFromJava.VERSION
}
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