java - 从子类访问私有(private)数据成员

Question

我想声明一个父类(super class)的数据成员，私有(private)的:

public abstract class superclass {
  private int verySensitive;

  abstract int setVerySensitive(int val); // must be overriden by subclass to work properly
}


public class subclass extends superclass {

  @Override
  protected int setVerySensitive(int val) {
    if (val > threshLow && val < threshHigh) // threshHigh is calculated in superclass constructor
       verySensitive = val;
  }
}

如您所见，我这里有一个问题:父类(super class)无法访问 verySensitive，因为它是私有(private)的，但我不想让 verySensitive 受到保护，因为它...敏感。

另请注意，setVerySensitive 是抽象的，因为只有在构建父类(super class)后才能检查有效值。

您能推荐一种摆脱这种“第 22 条军规”情况的优雅方法吗？

Answer 1

将检查抽象化，但将设置本身设为私有(private)怎么样？

public abstract class superclass {
  private int verySensitive;

  abstract boolean verifySensitiveValue(int val); // must be overriden by subclass to work properly

  private void setVerySensitiveValue(int val) {
    if (verifySensitiveValue(val)) {
      verySensitive = val;
    }
  }
}


public class subclass extends superclass {

  @Override
  protected boolean verifySensitiveValue(int val) {
    return (val > threshLow && val < threshHigh); // threshHigh is calculated in superclass constructor
  }
}