equals (문자열 비교하기)

public static void main(String[] args) {
double a = 3.14; // 실수형 변수 a에 3.14저장
double b = 5.15; // 실수형 변수 b에 5.15저장
System.out.println(a==b);
System.out.println(a!=b);


String c1 = "hello JAVA!"; //c1 문자열 변수에 "hello JAVA!" 값 저장
System.out.println(c1 == "hello JAVA!"); // true
System.out.println(c1.equals("hello JAVA!")); // true (문자열 비교할 떄는 equals사용)
// 문자열.equals(비교 문자열) : 문자열 비교하기
System.out.println(c1.equals("hello java!")); // 대/소문자 까지 비교