java获取当前月的天数

import java.text.ParseException;import java.text.SimpleDateFormat;import java.util.Calendar;import java.util.GregorianCalendar;public class d {public static void main(String[] args) {Calendar   cal   =   new   GregorianCalendar();        SimpleDateFormat oSdf = new SimpleDateFormat ("yyyy-MM");        try {            cal.setTime(oSdf.parse("2012-2"));        } catch (ParseException e) {            e.printStackTrace();        }            int num2 = cal.getActualMaximum(Calendar.DAY_OF_MONTH);            System.out.println(num2);}}

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