Java Data Type - 如何在给定的字符串日期获取月份的最后一天

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class Main {

  public static void main(String[] args) {

    Date today = new Date();

    Calendar calendar = Calendar.getInstance();
    calendar.setTime(today);

    calendar.add(Calendar.MONTH, 1);
    calendar.set(Calendar.DAY_OF_MONTH, 1);
    calendar.add(Calendar.DATE, -1);

    Date lastDayOfMonth = calendar.getTime();

    DateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
    System.out.println("Today            : " + sdf.format(today));
    System.out.println("Last Day of Month: " + sdf.format(lastDayOfMonth));
  }

}