java 获取当月的第一天和最后一天

直接上代码

//获取当月第一天和最后一天
Calendar cale = null;
cale = Calendar.getInstance();
// 获取当月第一天和最后一天
SimpleDateFormat formatTemp = new SimpleDateFormat("yyyy-MM-dd");
String firstday, lastday;
// 获取当前月的第一天
cale = Calendar.getInstance();
cale.add(Calendar.MONTH, 0);
cale.set(Calendar.DAY_OF_MONTH, 1);
firstday = formatTemp.format(cale.getTime());
// 获取当前月的最后一天
cale = Calendar.getInstance();
cale.add(Calendar.MONTH, 1);
cale.set(Calendar.DAY_OF_MONTH, 0);
lastday = formatTemp.format(cale.getTime());
System.out.println("firstday:"+firstday+" lastday:"+lastday);
String newDataUrl= dataUrl+"startDate="+firstday+"&"+"endDate"+lastday;

firstday:2020-04-01 lastday:2020-04-30

单独的算当前年和月，同样可以利用Calendar类

Calendar calendar = Calendar.getInstance();
System.out.println("开始时间是" + DateUtil.currentShortTime());
//获取当前年
int year = calendar.get(Calendar.YEAR);
//获取当前月份
int month = calendar.get(Calendar.MONTH +1);