달나라 노트

original source = www.w3schools.com 한번 동물의 울음소리를 출력해주는 코드를 작성해봅시다. class Animal { } class Cat extends Animal { } class Lion extends Animal { } class Dog extends Animal { } class Bark { public void bark(Animal animal) { if (animal instanceof Cat) { System.out.println("Cat sounds 야옹."); } else if (animal instanceof Lion) { System.out.println("Lion sounds 어흥."); } else if (animal instanceof Dog) { ..

Java에는 interface라는 것을 지원합니다. 일단 먼저 interface를 어떻게 사용할 수 있는지 알아봅시다. interface MemberInfo { public void name(); public void team(); } class Member implements MemberInfo{ public void name() { System.out.println("Bella"); } public void team() { System.out.println("Team 1"); } } public class MemberList { public static void main(String args[]) { Member member = new Member(); member.name(); member.team..

People.java public class People { String name; String planet; public void setName(String name) { this.name = name; } public void setPlanet(String planet) { this.planet = planet; } } Lisa.java public class Lisa extends People { public static void main(String args[]) { Lisa lisa = new Lisa(); System.out.println(lisa.name); System.out.println(lisa.planet); } } -- Result null null 위처럼 2개의 파일을 만들고 Li..

class PeopleInfo { String name; String planet; public void setName(String name) { this.name = name; } public void setPlanet(String planet) { this.planet = planet; } public void introduce() { System.out.println("Hello. I'm " + this.name + ". I live in " + this.planet + "."); } public void introduce(int x) { System.out.println("Hello. I'm " + this.name + ". I live in " + this.planet + ". And I'm "..