src/org/nutz/lang/Times.java
public static String getLastDayOfMonth() {
        Calendar cal = Calendar.getInstance();
        cal.set(Calendar.DATE, 1);
        cal.add(Calendar.MONTH, 1);
        cal.add(Calendar.DATE, -1);
        return format(DF_DATE, cal.getTime());
    }
public static String getLastDayOfMonth() {
        Calendar cal = Calendar.getInstance();
        cal.set(Calendar.DATE, 1);
        cal.add(Calendar.MONTH, 1);
        cal.add(Calendar.DATE, -1);
        return format(DF_DATE, cal.getTime());
    }
获取本月最后一天

@return 本月最后一天