java - 不断接收对其自身的赋值，并丢失方法体错误

Question

我已经完成这项作业几天了，但我无法解决这个问题。任务如下。

使用以下准则设计并实现一个代表 Person 的类以及 3 个子类:

a.创建一个名为 Person 的类及其三个名为 Employee、Student、Retired 的子类。

b.Person 具有以下数据字段:name、year_of_birth、isStuying 和 isEmployed。它还具有用于设置和获取每个字段的值的方法，以及计算当前年龄和显示人员状态的方法。 Person 类中还包含将 isStuying 和 isEmployed 字段设置为 false 的构造函数。如果您愿意，欢迎您添加其他数据字段和方法。

c.对于您的 Person、Employee、Student 和 Retired 类，getStatus 方法根据属性的当前值返回下表中显示的值:

1.最后，创建一个 Java 测试类来模拟使用您的 Person 类。在您的测试类中，您至少应该:a) 构造 Person 的 4 个实例，b) 打印实例的名称 c) 根据实例的年龄、isStuying 和 isEmployed 属性的值打印实例的状态。

以下代码实际上位于同一项目的 5 个不同文件中。

第一个文件:

public class Person2 {//begin class
    //declare variables
    String name;
    int year_of_birth;
    boolean isStudying;
    boolean isEmployed;
    int age;

public Person2(boolean isEmployed, boolean isStudying){//begin constructor
    this.isEmployed = false;
    this.isStudying = false;
}//end constructor

public int getYear(){//get year method
        return year_of_birth;
}//end method

public String getName(){//get name method
        return name;
}//end method

public boolean getEmployed(){//get employed method
        return isEmployed;
}//end method

public boolean getStudying(){//get employed method
        return isStudying;
    }//end method

public int getAge(int year_of_birth){//get year method
        age = 2014 - year_of_birth;
    return age;
}//end method

public int getStatus(int age);{//begin method
    this.age = age;
    if (age < 30 && isStudying == false && isEmployed == false || true){
        System.out.println(name + " is a student");
    }    else if(age > 30 || age < 65 && isStudying == false && isEmployed == false || true){
            System.out.println(name + " is an employee");
            }    else if(age > 65 && isStudying == false && isEmployed == false){
                    System.out.println(name + " is retired");
            }
}//end method

public void setName(String name){//set name method
        this.name = name;
}//end method

public void setYear (int year){//set year method
        this.year_of_birth = year;
}//end method

public void setEmployed(boolean employed){//set employed method
        this.isEmployed = employed;
}//end method

public void setAge (){//set year method
        this.age = age;
}//end method

public static void main(String[] args) {
        }

}//end class

第二个文件:

class Student extends Person2 {//begin class

    public Student(boolean isEmployed, boolean isStudying, int age) {//begin constructer
    super(isEmployed, isStudying);
    this.isEmployed = false;
    this.isStudying = true;
    }//end constructer          
}//end class

第三个文件:

class Retired extends Person2 {
    public Retired(boolean isEmployed, boolean isStudying) {//begin constructer
        super(isEmployed, isStudying);
        this.isEmployed = false;
        this.isStudying = false;
    }//end constructer        
}//end class

第四个文件:

class Employee extends Person2 {
    public Employee(boolean isEmployed, boolean isStudying) {//begin constructer
        super(isEmployed, isStudying);
        this.isEmployed = true;
        this.isStudying = false;
    }//end constructer  
}//end class

第五个文件:

public class PersonTest {//begin class
    public static void main(String[] args) {//begin main
    Person2 user1 = new Person2(false, true);
    user1.setName("John Doe");
    user1.setYear(1986);
    System.out.println("The clients name is " + user1.getName() + ".");
    System.out.println("The client is " + user1.getAge(1986) + ".");
    user1.getStatus(age); 
    //new user
    Person2 user2 = new Person2(true, false);
    user2.setName("Mary Joe");
    user2.setYear(1975);
    System.out.println("The clients name is " + user2.getName() + ".");
    System.out.println("The client is " + user2.getAge(1975) + ".");
    user2.getStatus(age);
    //new user
    Person2 user3 = new Person2(true, false);
    user3.setName("Forrest Burtner");
    user3.setYear(1924);
    System.out.println("The clients name is " + user3.getName() + ".");
    System.out.println("The client is " + user3.getAge(1924) + ".");
    user3.getStatus(age);
    //new user
    Person2 user4 = new Person2(false, false);
    user4.setName("John Connor");
    user4.setYear(1910);
    System.out.println("The clients name is " + user4.getName() + ".");
    System.out.println("The client is " + user4.getAge(1910) + ".");
    user3.getStatus(age);
    }//end main     
}//end class

我所有的问题似乎都源于 getStatus 方法，不确定我做错了什么。任何帮助将不胜感激。

Answer 1

Person2 类中的更改，如您的方法中包含拼写错误 public String getStatus(int Age); 即最后的 分号，我不知道编译器如何处理它，通常它被视为空语句，并且当您返回通常为 String 的状态时，因此将方法的类型从 int 更改为字符串，并在 PersonTest 类中获取了该方法的年龄用户并使用年龄调用 getStatus() 并显示结果。

public String getStatus(int age){
    this.age = age;
    if (age < 30 && isStudying == true && isEmployed == false){
        return name + " is a student";
    }    else if((age > 30 || age < 65) && isStudying == false && isEmployed == true){
        return name + " is an employee";
    }    else if(age > 65 && isStudying == false && isEmployed == false){
        return name + " is retired";
    }
    return null;
}

PersonTest 类

public class PersonTest {
    public static void main(String[] args) {
        Person2 user1 = new Person2(false, true);
        user1.setName("John Doe");
        user1.setYear(1986);
        System.out.println("The clients name is " + user1.getName() + ".");
        System.out.println("The client is " + user1.getAge(1986) + ".");
        System.out.println(user1.getStatus(user1.getAge(1986)));

        Person2 user2 = new Person2(true, false);
        user2.setName("Mary Joe");
        user2.setYear(1975);
        System.out.println("The clients name is " + user2.getName() + ".");
        System.out.println("The client is " + user2.getAge(1975) + ".");
        System.out.println(user2.getStatus(user2.getAge(1975)));

        Person2 user3 = new Person2(false, false);
        user3.setName("Forrest Burtner");
        user3.setYear(1924);
        System.out.println("The clients name is " + user3.getName() + ".");
        System.out.println("The client is " + user3.getAge(1924) + ".");
        System.out.println(user3.getStatus(user3.getAge(1924)));

        Person2 user4 = new Person2(false, false);
        user4.setName("John Connor");
        user4.setYear(1910);
        System.out.println("The clients name is " + user4.getName() + ".");
        System.out.println("The client is " + user4.getAge(1910) + ".");
        System.out.println(user3.getStatus(user4.getAge(1910)));
    }
}

一切都会顺利