构造函数两个类上 java

Question

我正在尝试访问比我高两级的抽象类中的构造函数。

    public abstract class Person{
        protected String name;
    public Person(String name){
         if name.length() <= 12)
            this.name = name;
         else 
            this.name = name.substring(0,12);
    }
    public final String returnName(){
       return name;
    }
   }
public class employee extends person{
        public employee(string firstname, string gender){
               super(firstname);
               this.gender =gender;
         }
}
public class dependent extends employee{
        public dependent(string firstname, string gender, string relation){
             super(firstname);
             super(gender);
             this.relation = relation;
        }

如何从依赖类（下面两个级别）调用抽象类的构造函数？

Answer 1

好的，首先，以下是将两个参数传递给 Employee 构造函数的方法：

super(firstname, gender);

其次，无需从依赖构造函数调用 Person 构造函数。当 Dependent 调用 Employee 构造函数时，这将自动发生，因为 Employee 构造函数随后调用 Person 1。

Answer 2

您要查找的内容如下所示，请注意，方法参数以大写和驼峰大小写开头，并以小写字母命名。字符串必须是大写String name，也请注意，您已经在name上引入了受保护的成员作用域请参阅以下关于在 Java 中的含义的文章，默认、公共、受保护和私有之间的区别

  public abstract class Person
  {
    protected String name;
    public Person(String name)
    {
      if (name.length() <= 12)
      {
        this.name = name;
      }
      else
      {
        this.name = name.substring(0, 12);
      }
    }
    public final String returnName()
    {
      return name;
    }
  }
  public class Employee extends Person
  {
    private String gender = null;
    public Employee(String firstName, String gender)
    {
      super(firstName);
      this.gender = gender;
    }
  }
  public class Dependent extends Employee
  {
    private String relation = null;
    public Dependent(String firstName, String gender, String relation)
    {
      super(firstName, gender);
      this.relation = relation;
    }
  }

如果您需要访问这些关系和性别，则需要添加访问这些方法

Answer 3

试试这个：

public class employee extends Person{
        public employee(String firstname, String gender){
               super(firstname);
               this.gender =gender;
         }
}
public class dependent extends employee{
        public dependent(String firstname, String gender, String relation){
             super(firstname,gender);
             this.relation = relation;
        }