java获取日期

关于java获取日期（当月第一天和最后一天）

public class Test {

	public static void main(String[] args) {
		 SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd");
         //String today=format.format(new Date());
		 Calendar cal = Calendar.getInstance();
         //String today = format.format(cal.getTime());
         //String[] day=today.split("-");
         //String MonthFristDay=day[0]+"-"+day[1]+"-"+"01";
      	cal.set(Calendar.DAY_OF_MONTH,1);//月初
      	String firstDate=format.format(cal.getTime());
      	final int lastDay = cal.getActualMaximum(Calendar.DAY_OF_MONTH); 
  	    cal.set(Calendar.DAY_OF_MONTH,lastDay);  //月末
      	String lastDate=format.format(cal.getTime());
         //System.out.println(today);
         System.out.println(firstDate);
         System.out.println(lastDate);
	}

}