java 요일을 받아서 달력 완성하기

package test;

import java.util.Scanner;

public class Calendar {

    private static int day(String dateInput) {
        if (dateInput.equals("mo")) {
            return 1;
        }
        if (dateInput.equals("tu")) {
            return 2;
        }
        if (dateInput.equals("we")) {
            return 3;
        }
        if (dateInput.equals("th")) {
            return 4;
        }
        if (dateInput.equals("fr")) {
            return 5;
        }
        if (dateInput.equals("sa")) {
            return 6;
        }
        if (dateInput.equals("su")) {
            return 7;
        }
        return 0;

    }

    public static void main(String[] args) {

        System.out.println("년도를 입력하세요");
        Scanner scanner = new Scanner(System.in);
        int yearInput = scanner.nextInt();
        System.out.println("월을 입력하세요");
        int monthInput = scanner.nextInt();
        System.out.println("요일을 입력하세요");
        String dateInput = scanner.next();

        day(dateInput);

        System.out.println(" su mo tu we th fr sa");
        System.out.println("---------------------");

        int[] month = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
        int[] leapMonth = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
        // 윤년,평년
        if ((yearInput % 4 == 0 || yearInput % 100 == 0) && yearInput % 400 == 0) {
            month = leapMonth;
        }
        // 첫줄 띄어쓰기
        if (0 < day(dateInput)) {
            for (int a = 1; a <= day(dateInput); a++) {
                System.out.print("   ");
            }
        }
        // 첫줄 출력
        for (int c = 1; c <= (7 - day(dateInput)); c++) {
            System.out.printf("%3d", c);

        }
        System.out.println();

        // 둘째줄
        for (int i = 1; i <= (month[monthInput - 1] - (7 - day(dateInput))); i++) {

            System.out.printf("%3d", i + (7 - day(dateInput)));
            // 7일로 나누어서 출력
            if (i % 7 == 0) {
                System.out.println();
            }
        }

        scanner.close();
    }

}