String 비교 equalsString str1 = "Hello";String str2 = "hello";System.out.println(str1.equals(str2)); // falseSystem.out.println(str1.equalsIgnoreCase(str2)); // true contentEquals StringBuffer, StringBuilder등 CharSequence를 구현한 객체를 비교String str = "Hello";StringBuffer stringBuffer = new StringBuffer("Hello");StringBuilder stringBuilder = new StringBuilder("Hello");System.out.println(str.contentEqual..