JAVA__54_Stream_1_intStream_forEach

main 실행문

import java.util.stream.IntStream;

class Main {
    public static void main(String[] args) {
        new ver1().run();
        System.out.printf("\n");
        new ver2().run();
        System.out.printf("\n");
        new ver3().run();
        System.out.printf("\n");
        new ver4().run();
        System.out.printf("\n");
        new ver5().run();
    }
}

for문 방식

class ver1{
    public void run(){
        for (int i = 1; i <= 10; i++) {
            System.out.printf("%d",i);
        }
    }
}

Stream 기본

class ver2 {
    public void run() {
        IntStream.range(1, 11)
                .forEach(e -> {
                    System.out.printf("%d", e);
                });
    }
}

Stream 방식1 - foreach

class ver3 {
    public void run() {
        IntStream.rangeClosed(1, 10)
                .forEach(e -> {
                    System.out.printf("%d", e);
                });
    }
}

Stream 방식2 - 1줄이하의 단순구성 {}소괄호 생략가능

class ver4 
    public void run(){
        IntStream.rangeClosed(1,10)
                .forEach( e -> System.out.printf("%d",e) );
    }

Stream 방식3 - 축약

class ver5 {
    public void run(){
        IntStream.rangeClosed(1,10)
                .forEach(System.out::println);
    }
}