import java.text.ParseException; 
import java.text.SimpleDateFormat; 
import java.util.Calendar; 
import java.util.Date; 

public class DateTest { 

  public static void main(String[] args) throws ParseException { 
    Calendar now = Calendar.getInstance(); 
    System.out.println("年: " + now.get(Calendar.YEAR)); 
    System.out.println("月: " + (now.get(Calendar.MONTH) + 1) + ""); 
    System.out.println("日: " + now.get(Calendar.DAY_OF_MONTH)); 
    System.out.println("时: " + now.get(Calendar.HOUR_OF_DAY)); 
    System.out.println("分: " + now.get(Calendar.MINUTE)); 
    System.out.println("秒: " + now.get(Calendar.SECOND)); 
    System.out.println("当前时间毫秒数：" + now.getTimeInMillis()); 
    System.out.println(now.getTime()); 

    Date d = new Date(); 
    System.out.println(d); 
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 
    String dateNowStr = sdf.format(d); 
    System.out.println("格式化后的日期：" + dateNowStr); 

    String str = "2012-1-13 17:26:33"; //要跟上面sdf定义的格式一样 
    Date today = sdf.parse(str); 
    System.out.println("字符串转成日期：" + today); 
  } 
}