이전복습 (day19)

오버로딩

package day20.ex05;

public class Printer {

	void println(int a) {
		System.out.println(a);
	}
	void println(boolean a) {
		System.out.println(a);
	}
	void println(double a) {
		System.out.println(a);
	}
	void println(String a) {
		System.out.println(a);
	}
}

package day20.ex05;

public class Printer_Ex {
	public static void main(String[] args) {
		Printer printer = new Printer();
		printer.println(10);
		printer.println(true);
		printer.println(5.7);
		printer.println("홍길동");
	}
}

boolean

package day20.ex05;

public class MemberService {
	
		boolean login(String id, String passward) {
//			if(id == "hong" && passward == "12345") {
			if(id.equals("hong") && passward.equals("12345")) {	// 문자열비교에는 .equals가 좋음
					return true; 
			}else {
					return false;
			}
		}
		
		void logout(String id) {
			System.out.println("로그아웃되었습니다.");
		}
}

package day20.ex05;

public class MemberService_Ex {
	public static void main(String[] args) {
		MemberService ms = new MemberService();
		
		boolean result = ms.login("hong", "12345");
		
		if(result) {
			System.out.println("로그인 되었습니다.");
//			ms.logout("hong");
		} else {
			System.out.println("id 또는 password가 올바르지 않습니다.");
		}
		
	}
}