java 現在の曜日を取得する

Calendar calendar = Calendar.getInstance();

calendar.get(Calendar.DAY_OF_WEEK) - 1 
// SUNDAY(1)、MONDAY(2)、TUESDAY(3)、WEDNESDAY(4)、THURSDAY(5)、FRIDAY(6)、SATURDAY(7) 

import java.util.Calendar;

public class App {
    public static void main(String[] args) throws Exception {

        String[] str = {"日", "月", "火", "水", "木", "金", "土"};

        Calendar calendar = Calendar.getInstance();

        System.out.println(str[calendar.get(Calendar.DAY_OF_WEEK) - 1]); // 土

    }
}