java - 尝试从另一个子类继承时出错？

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Java Constructor Inheritance
                                
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public class Vehicle {

  private double speed;
  private int wheels;

  public Vehicle() {

  }

  public Vehicle(double speed, int wheels) {
    this.speed = speed;
    this.wheels = wheels;
  }

}


public class Motorcycle extends Vehicle {

  private double engineSize;

  public Motorcycle(double speed, double engine) {
    super(speed, 2);
    this.engineSize = engine;
  }

}


public class Moped extends Motorcycle {


}

由于Mope扩展了Motorcycle，为什么会告诉我Moped需要创建构造函数？我希望Moped在没有任何构造函数的情况下工作。

最佳答案

由于Motorcycle没有默认的构造函数，因此您无法在Moped中使用它-但可以为Moped添加一个空的构造函数-例如，

public class Moped extends Motorcycle {
    public Moped() {
        super(70, 50); //<-- or whatever values you want
    }
}