java version

java 8

try with resource  : doc 보기

        try (Connection connection = DriverManager.getConnection(url, username, password)){
            System.out.println("Connection create:"+connection);
        }

lambda : doc 보기

    public static void main(String[] args) {
 
        List<Person> people = Arrays.asList(//
                new Person("Charles", "Dickens", 60), new Person("Lewis", "Carroll", 42),
                new Person("Thomas", "Carlyle", 51), new Person("Charlotte", "Brante", 45),
                new Person("Mattew", "Arnold", 39));
        //--> 이부분
        System.out.println("Printing all persons");
        //System.out.println(person)  :
        // p -> method(p)
        //person -> System.out.println(person)
        printConditionaly(people, person -> true, System.out::println);
    }
 
    private static void printConditionaly(List<Person> people, Predicate<Person> predicate, Consumer<Person> consumer) {
        for (Person person : people) {
            if (predicate.test(person))
                consumer.accept(person);
        }
    }