java -- abstract

在java中，一个类被abstract修饰则被称作抽象类，抽象类中被abstract修饰的方法则被称作抽象方法，abstract抽象方法只允许声明，不允许实现。

public abstract class Person {
    public abstract String getDescription();
    private String name;

    public Person(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }
}
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public class Student extends Person{
   private String major;

    public Student(String name, String major) {
        super(name);
        this.major = major;
    }

    @Override
    public String getDescription() {
        return  "this is a student of " + major;
    }
}
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public class PersonTest {
    public static void main(String[] args) {
        var person = new Person[2];
        person[0] = new Student("aaa", "bbbb");
        person[1] = new Employee("testCode", 1 , LocalDate.now());
        for (Person p:person) {
            System.out.println(p.getDescription() + "=====" + p.getName());
        }
    }
}

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