GregorianCalendar.clone() doesn't create separate objects

Name: mc57594 Date: 02/07/97


If you clone a GregorianCalendar, you get references to the
same object. I you modify one, all of them get modified:
import java.io.*;
import java.util.*;
class Test {
  public static void main(String[] args) {
    String s;
    
    GregorianCalendar d1, d2, d3;
    d1 = new GregorianCalendar(1997,1,16);
    d2 = (GregorianCalendar) d1.clone();
    d3 = (GregorianCalendar) d1.clone();
    d1.set(Calendar.HOUR, 9);
    d2.set(Calendar.HOUR, 10);
    d3.set(Calendar.HOUR, 11);
    System.out.println(d1.getTime().toString() +
                       "\n" + d2.getTime().toString() +
                       "\n" + d3.getTime().toString());
  }
}

hoth% java Test
Sun Feb 16 11:00:00 GMT+03:00 1997
Sun Feb 16 11:00:00 GMT+03:00 1997
Sun Feb 16 11:00:00 GMT+03:00 1997
hoth%

company - Sun Microsystems , email - ###@###.###
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