java 获取当前年份 月份,当月第一天和最后一天

记录一下：

Calendar cale = Calendar.getInstance();  
        int year = cale.get(Calendar.YEAR);  
        int month = cale.get(Calendar.MONTH) + 1;  
        int day = cale.get(Calendar.DATE);  
        int hour = cale.get(Calendar.HOUR_OF_DAY);  
        int minute = cale.get(Calendar.MINUTE);  
        int second = cale.get(Calendar.SECOND);  
        int dow = cale.get(Calendar.DAY_OF_WEEK);  
        int dom = cale.get(Calendar.DAY_OF_MONTH);  
        int doy = cale.get(Calendar.DAY_OF_YEAR);  
  
        System.out.println("Current Date: " + cale.getTime());  
        System.out.println("Year: " + year);  
        System.out.println("Month: " + month);  
        System.out.println("Day: " + day);  
        System.out.println("Hour: " + hour);  
        System.out.println("Minute: " + minute);  
        System.out.println("Second: " + second);  
        System.out.println("Day of Week: " + dow);  
        System.out.println("Day of Month: " + dom);  
        System.out.println("Day of Year: " + doy);  
  
        // 获取当月第一天和最后一天  
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");  
        String firstday, lastday;  
        // 获取前月的第一天  
        cale = Calendar.getInstance();  
        cale.add(Calendar.MONTH, 0);  
        cale.set(Calendar.DAY_OF_MONTH, 1);  
        firstday = format.format(cale.getTime());  
        // 获取前月的最后一天  
        cale = Calendar.getInstance();  
        cale.add(Calendar.MONTH, 1);  
        cale.set(Calendar.DAY_OF_MONTH, 0);  
        lastday = format.format(cale.getTime());  
        System.out.println("本月第一天和最后一天分别是 ： " + firstday + " and " + lastday);  
  
        // 获取当前日期字符串  
        Date d = new Date();  
        System.out.println("当前日期字符串1：" + format.format(d));  
        System.out.println("当前日期字符串2：" + year + "/" + month + "/" + day + " "  
                + hour + ":" + minute + ":" + second);