java获取当前时间的几种方法

import java.util.*;

public class D
{
public static void main(String []abc)
{
int y,m,d,h,mi,s;
Calendar cal=Calendar.getInstance();
y=cal.get(Calendar.YEAR);
m=cal.get(Calendar.MONTH);
d=cal.get(Calendar.DATE);
h=cal.get(Calendar.HOUR_OF_DAY);
mi=cal.get(Calendar.MINUTE);
s=cal.get(Calendar.SECOND);
System.out.println("现在时刻是"+y+"年"+m+"月"+d+"日"+h+"时"+mi+"分"+s+"秒");
}

}
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public class Main{
public static void main(String[] args){
java.util.Calendar c=java.util.Calendar.getInstance();
java.text.SimpleDateFormat f=new java.text.SimpleDateFormat("yyyy年MM月dd日hh时mm分ss秒");
System.out.println(f.format(c.getTime()));
}
}

##########################################################################

public String GetNowDate(){
String temp_str="";
Date dt = new Date();
//最后的aa表示“上午”或“下午”    HH表示24小时制    如果换成hh表示12小时制
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss aa");
temp_str=sdf.format(dt);
return temp_str;
}

1.

Date day=new Date();

SimpleDateFormat df =  new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(df.format(day));

2. 

SimpleDateFormat df =  new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(df.format(System.currentTimeMillis()));

3.

Calendar c = Calendar.getInstance();

int year=c.get(Calender.YEAR);

int month=c.get(Calender.MONTH);

int date=c.get(Calender.DATE);

int hour=c.get(Calender.HOUR_OF_DAY);

int minute=c.get(Calender.MINUTE);

int second=c.get(Calender.SECOND);

System.out.println(year+"/"+month+"/"+date+"  "+hour+":"+minute+":"+second);

4.

Date date=new Date();

String.format("%tY",date);

String year=String.format("%tY",date);

String month=String.format("%tB",date);

String day=String.format("%te",date);

System.out.println("今天是："+year+"-"+month+"-"+day);