Hi !
Featured games (83)
games approved by the League of Dukes
Games in Showcase (593)
Games in Android Showcase (168)
games submitted by our members
Games in WIP (647)
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 958 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.

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.

Riven (7 views)
2015-07-03 11:22:16

deepthought (40 views)
2015-06-30 15:39:44

deepthought (44 views)
2015-06-30 15:39:09

deepthought (54 views)
2015-06-30 15:36:52

Za\'Anzabar (24 views)
2015-06-29 05:44:54

TritonDreyja (41 views)
2015-06-24 17:10:40

CopyableCougar4 (39 views)
2015-06-23 00:34:45

BurntPizza (43 views)
2015-06-21 20:36:46

cookiecompiler (85 views)
2015-06-11 15:42:53

cookiecompiler (48 views)
2015-06-11 15:41:14
How Do I Expand My Game?
by bashfrog
2015-06-14 11:34:43

List of Learning Resources
by PocketCrafter7
2015-05-31 05:37:30

Intersection Methods
by Roquen
2015-05-29 08:19:33

List of Learning Resources
by SilverTiger
2015-05-05 10:20:32

How to: JGO Wiki
by Mac70
2015-02-17 20:56:16

2D Dynamic Lighting
by ThePixelPony
2015-01-01 20:25:42

How do I start Java Game Development?
by gouessej
2014-12-27 19:41:21

Resources for WIP games
by kpars
2014-12-18 10:26:14 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‑
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!