java的Uml类图

我是java的新手。我正在尝试创建一个库系统

哪些类应该是抽象的？我需要更多的课程吗

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是的，您需要很多类，您的类应该如下所示：

class Person{
   //attributes, getters and setters
}

class User extends Person{
   //attributes, getters and setters
}

class Members extends Person{
}

class Librarian extends Person{
}

class Book{
   //attributes, getters and setters
}

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欢迎来到堆栈溢出！看起来你可能在请求家庭作业帮助。虽然我们对此本身没有问题，但请注意这些，并相应地编辑您的问题。（即使这不是家庭作业，也请考虑建议。）由于多级继承，Guest（）、Members（）、Library（）类将具有所有Person（）类属性。User（）类也将具有所有Person（）类属性。我认为这就是您应该如何编写代码。

public class Person {
    private String FirstName;
    private String LastName;
    private String Gender;
    private String Contact;
    private String Email;

    public Person() {
    }

    public Person(String FirstName, String LastName, String Gender, String Contact, String Email) {
        this.FirstName = FirstName;
        this.LastName = LastName;
        this.Gender = Gender;
        this.Contact = Contact;
        this.Email = Email;
    }

    public String getFirstName() {
        return FirstName;
    }

    public void setFirstName(String FirstName) {
        this.FirstName = FirstName;
    }

    public String getLastName() {
        return LastName;
    }

    public void setLastName(String LastName) {
        this.LastName = LastName;
    }

    public String getGender() {
        return Gender;
    }

    public void setGender(String Gender) {
        this.Gender = Gender;
    }

    public String getContact() {
        return Contact;
    }

    public void setContact(String Contact) {
        this.Contact = Contact;
    }

    public String getEmail() {
        return Email;
    }

    public void setEmail(String Email) {
        this.Email = Email;
    }

}
public class User extends Person {
    private String Password;
    private String Username;
    boolean isEnabled;

    public User() {
    }

    public User(String Password, String Username, boolean isEnabled) {
        this.Password = Password;
        this.Username = Username;
        this.isEnabled = isEnabled;
    }

    public String getPassword() {
        return Password;
    }

    public void setPassword(String Password) {
        this.Password = Password;
    }

    public String getUsername() {
        return Username;
    }

    public void setUsername(String Username) {
        this.Username = Username;
    }

    public boolean isIsEnabled() {
        return isEnabled;
    }

    public void setIsEnabled(boolean isEnabled) {
        this.isEnabled = isEnabled;
    }

}
public class Guest extends User {

    public Guest() {
    }

    public Guest(String Password, String Username, boolean isEnabled) {
        super(Password, Username, isEnabled);
    }

    public void App(){

    }
    }
public class Members extends User{

    public Members() {
    }

    public Members(String Password, String Username, boolean isEnabled) {
        super(Password, Username, isEnabled);
    }

}
public class Libararian extends User {

    public Libararian() {

    }
     public Libararian(String Password, String Username, boolean isEnabled) {
        super(Password, Username, isEnabled);
    }

}
public class Book {
    private String Title;
    private String Publisher;
    private String Category;

    public Book(String Title, String Publisher, String Category) {
        this.Title = Title;
        this.Publisher = Publisher;
        this.Category = Category;
    }

    public Book() {
    }

    public String getTitle() {
        return Title;
    }

    public void setTitle(String Title) {
        this.Title = Title;
    }

    public String getPublisher() {
        return Publisher;
    }

    public void setPublisher(String Publisher) {
        this.Publisher = Publisher;
    }

    public String getCategory() {
        return Category;
    }

    public void setCategory(String Category) {
        this.Category = Category;
    }

}