Calendar类处理日期

Question

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
Calendar calendar  = Calendar.getInstance();
calendar.setTime(sdf.parse("2009-3-1 12:00:00"));
System.out.println(sdf.format(calendar.getTime()));
System.out.println(calendar.get(calendar.AM_PM));
System.out.println(calendar.get(calendar.HOUR_OF_DAY));我们我获取的时间会是0呢，我想得到12，有什么办法没有

Answer 1

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
public class testDate {
public static void main(String []args) throws ParseException{
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 
Calendar calendar  = Calendar.getInstance(); 
calendar.setTime(sdf.parse("2009-3-1 12:00:00")); 
System.out.println(sdf.format(calendar.getTime())); 
System.out.println(calendar.get(Calendar.AM_PM)); 
System.out.println(calendar.get(Calendar.HOUR_OF_DAY)); 
}
}

Answer 2

yyyy-MM-dd HH:mm:ss  大写HH才是24小时制的

Answer 3

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); 12小时制
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 24小时制

Answer 4

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); 
Calendar calendar  = Calendar.getInstance(); 
try {
calendar.setTime(sdf.parse("2009-3-1 12:00:00"));
} catch (ParseException e) {
e.printStackTrace();
}
String a= sdf.format(calendar.getTime());
System.out.println(a); 
System.out.println(a.substring(11, 13).replace(":", "").trim());

Answer 5

public static void main(String[] args){
//SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//12小时制
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//24小时制
Calendar calendar  = Calendar.getInstance();
try {
calendar.setTime(sdf.parse("2009-3-1 12:00:00"));
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println(sdf.format(calendar.getTime()));
//System.out.println(calendar.get(calendar.AM_PM));
System.out.println(calendar.get(calendar.HOUR_OF_DAY)); 
}

Answer 6

public String time()
{
Calendar c=Calendar.getInstance();
return Integer.toString(c.get(Calendar.YEAR))+"-"+Integer.toString(c.get(Calendar.MONTH)+1)+
"-"+Integer.toString(c.get(Calendar.DAY_OF_MONTH))+" "+Integer.toString(c.get(Calendar.HOUR_OF_DAY))+
":"+Integer.toString(c.get(Calendar.MINUTE))+":"+Integer.toString(c.get(Calendar.SECOND ));
}