Java-Gaming.org Hi !
Featured games (90)
games approved by the League of Dukes
Games in Showcase (683)
Games in Android Showcase (196)
games submitted by our members
Games in WIP (750)
games currently in development
News: Read the Java Gaming Resources, or peek at the official Java tutorials
 
    Home     Help   Search   Login   Register   
Pages: [1]
  ignore  |  Print  
  Making a copy versus changing a pointer location.  (Read 1084 times)
0 Members and 1 Guest are viewing this topic.
Offline Manfred

Senior Newbie




Java games rock!


« Posted 2004-10-26 22:26:34 »

I'd like to copy and Object, not set a pointer.  Like so:

MyObject o1 = new MyObject();
MyObject o2 = o1;

Seems as though o2 is just pointing to o1.  I want o2 to be a copy of o1.  How might I do that?
Offline oNyx

JGO Coder


Medals: 2


pixels! :x


« Reply #1 - Posted 2004-10-27 00:01:20 »

You always only have references to objects. So in your example...

MyObject o1 = new MyObject();
MyObject o2 = o1;

...neither o1 or o2 are the object. It's just a reference. So if you do something like...

MyObject o1 = new MyObject("one");
MyObject o2 = o1;
MyObject o1 = new MyObject("two");

o2 will hold a reference to "one" whereas o1 will hold a reference to "two" (the new object). [And if there isn't a reference to an object it will get garbage collected]

If you want to create a copy you need to use clone(); like...

MyObject o1 = new MyObject("one");
MyObject o2 = o1.clone();

then you'll have two different but (content wise) identical objects.

Btw you'll need to implement the Cloneable interface.
http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Cloneable.html

弾幕 ☆ @mahonnaiseblog
Offline Manfred

Senior Newbie




Java games rock!


« Reply #2 - Posted 2004-10-27 12:44:26 »

Thank you again, sir.
Pages: [1]
  ignore  |  Print  
 
 
You cannot reply to this message, because it is very, very old.

 
orrenravid (166 views)
2016-07-16 03:57:23

theagentd (236 views)
2016-07-11 14:28:54

Hydroque (319 views)
2016-07-06 05:56:57

Hydroque (471 views)
2016-07-03 08:52:54

GrandCastle (353 views)
2016-07-01 09:13:47

GrandCastle (345 views)
2016-07-01 09:09:45

CopyableCougar4 (400 views)
2016-06-25 16:56:52

Hydroque (378 views)
2016-06-22 02:17:53

SwampChicken (348 views)
2016-06-20 13:22:57

SwampChicken (290 views)
2016-06-20 13:22:49
Making a Dynamic Plugin System
by Hydroque
2016-06-25 00:13:25

Java Data structures
by BinaryMonkL
2016-06-13 21:22:09

Java Data structures
by BinaryMonkL
2016-06-13 21:20:42

FPS Camera Tutorial
by Hydroque
2016-05-22 05:40:58

Website offering 3D Models specifically for games for free
by vusman
2016-05-18 17:23:09

Website offering 3D Models specifically for games for free
by vusman
2016-05-09 08:50:56

Website offering 3D Models specifically for games for free
by vusman
2016-05-06 11:10:21

Website offering 3D Models specifically for games for free
by vusman
2016-04-29 12:56:17
java-gaming.org is not responsible for the content posted by its members, including references to external websites, and other references that may or may not have a relation with our primarily gaming and game production oriented community. inquiries and complaints can be sent via email to the info‑account of the company managing the website of java‑gaming.org
Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines | Managed by Enhanced Four Valid XHTML 1.0! Valid CSS!