KaiquanMah/TurkuBasicOOPinJava

1In Java, each class can DIRECTLY INHERIT UP TO 1 CLASS. 2In fact, in Java, every class inherits (unless otherwise specified) the PARENT CLASS 'Object'. 3Thus, all Java classes are DIRECT OR INDIRECT heirs of the class 'Object'.4 5Inheritance is indicated by the keyword 'extends'. 6In fact, the English version is perhaps clearer in meaning than inheritance: 7the INHERITING/CHILD class 'extends' the functionality of the PARENT class, 8since new properties can be added to the child class in addition to those of the parent class.9 10 11 12As an example, let us first consider the class 'Person'. 13The class constructor is currently empty, we will return to this later:14class Person {15    private String name;16    private String email;17 18    // CONSTRUCTOR - EMPTY19    public Person() {}20 21    public String getName() {22        return name;23    }24 25    public void setName(String name) {26        this.name = name;27    }28 29    public String getEmail() {30        return email;31    }32 33    public void setEmail(String email) {34        this.email = email;35    }  36}37 38 39Now you can define the class Student, which inherits the Person class. 40So the Student class has all the features of the Person class (but no new implementation of its own yet).41class Student extends Person { }42 43 44Similarly, a class Teacher can be defined, which also inherits the Person class. 45The teacher now also has all the attributes of a person:46class Teacher extends Person { }47 48 49 50