java 获取当月的第一天和最后一天

public static String getFirstDayOfMonth(Date currentDate) {    simpleDateFormat.applyPattern(DATE_FORMAT_006);    Calendar cal = Calendar.getInstance();    cal.setTime(currentDate);    // 获取前月的第一天    cal.add(Calendar.MONTH, 0);    cal.set(Calendar.DAY_OF_MONTH, 1);    cal.set(Calendar.HOUR, 0);    cal.set(Calendar.MINUTE, 0);    cal.set(Calendar.SECOND, 0);    return simpleDateFormat.format(cal.getTime());}public static String getLastDayOfMonth(Date currentDate) {    simpleDateFormat.applyPattern(DATE_FORMAT_006);    Calendar cal = Calendar.getInstance();    cal.setTime(currentDate);    // 获取前月的最后一天      cal.set(Calendar.DATE, cal.getActualMaximum(Calendar.DATE));    return simpleDateFormat.format(cal.getTime());}