求教大神为啥这里的getTime返回值不是毫秒数？

[MeterO_]

import java.util.Date;
import java.util.Calendar;
public class TestDateDemo{
public static void main(String args[ ]){
Date today = new Date();
System.out.println("Today's date is :"+today);
Calendar c = Calendar.getInstance();
c.set(1997,2,3);
Calendar d = c;
System.out.println("The initial time is :"+c.get(Calendar.YEAR)+"."+c.get(Calendar.MONTH)+"."+c.get(Calendar.DATE));
c.add(Calendar.DATE,1);
c.add(Calendar.HOUR_OF_DAY,1);
System.out.println("The new date is :"+c.get(Calendar.YEAR)+"."+c.get(Calendar.MONTH)+"."+c.get(Calendar.DATE));
long days = (c.getTime() - d.getTime())/(1000*60*60*24);
System.out.println("Two dates differ by "+days+"days");
}
}

[大隐藏于寺]

以下是Calendar类的getTime()方法的源代码,可以看到使用getTime()方法时,返回的是一个Date类对象,而你想用Calendar类对象获取毫秒值应该使用getTimeInMillis()方法.

    /**
     * Returns a <code>Date</code> object representing this
     * <code>Calendar</code>'s time value (millisecond offset from the <a
     * href="#Epoch">Epoch</a>").
     *
     * @return a <code>Date</code> representing the time value.
     * @see #setTime(Date)
     * @see #getTimeInMillis()
     */
    public final Date getTime() {
        return new Date(getTimeInMillis());
    }

[萧乡月夜]

楼上正解。。