java 时间处理

package yingjun.test;


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



public class DateTest {
   public static void main(String[] args) throws Exception {
	   
	long mstime=System.currentTimeMillis();//获取当前的毫秒数
	
	// Date转化为String   
	Date date1=new Date();
    String d=new SimpleDateFormat("yyyy-MM-dd hh:mm:ss").format(date1); 
    System.out.println(d); 
    
    // String转化为Date
    String str1="2013-06-01";
    SimpleDateFormat sdf1= new SimpleDateFormat("yyyy-MM-dd");
    Date date2= sdf1.parse(str1);
    System.out.println(date2);

    
    // Date转化为Calendar    
    Calendar cal1=Calendar.getInstance(); 
    Date date3=new Date();
    cal1.setTime(date3); 
    System.out.println(cal1.get(Calendar.DAY_OF_YEAR)); //获取今天是本年的第几天。
    System.out.println(cal1.get(Calendar.YEAR));//年
    System.out.println(cal1.get(Calendar.MONTH)+1);//月
    System.out.println(cal1.get(Calendar.DAY_OF_MONTH));//日
    System.out.println(cal1.get(Calendar.HOUR_OF_DAY));//时
    System.out.println(cal1.get(Calendar.MINUTE));//分
    System.out.println(cal1.get(Calendar.SECOND));//秒
   
    
    // Calendar转化为Date    
    Calendar cal2=Calendar.getInstance(); 
    Date date4=cal2.getTime(); 
    System.out.println(date4);
    
    
   }
}