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Serialisation problem

GregK
Greenhorn

Joined: Oct 24, 2005
Posts: 15
Hi

Basically I wantto do a save and a load of 2 variables. Which seems to work because the save file stores them when I look to see.

It's loading the file to the fields where I get problems - java.lang.ClassCastException: java.lang.String



theres the load game code.
Joe Ess
Bartender

Joined: Oct 29, 2001
Posts: 8927
    
    9

Did you use an ObjectOutputStream to write objects of the same class in the same order? Sounds like you wrote Strings to the file.


"blabbing like a narcissistic fool with a superiority complex" ~ N.A.
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GregK
Greenhorn

Joined: Oct 24, 2005
Posts: 15
Yes I wrote 2 strings to a file, can this not be done and deserialised just the same?
GregK
Greenhorn

Joined: Oct 24, 2005
Posts: 15
Joe Ess
Bartender

Joined: Oct 29, 2001
Posts: 8927
    
    9

No. How is ObjectInputStream supposed to know that a String in a file corresponds to a Room object? To read a Room out, you have to serialize a Room instance.
GregK
Greenhorn

Joined: Oct 24, 2005
Posts: 15
sorry i'm new to serilization, which is why i posted in the beginner forum.

How do I do something like that?
Joe Ess
Bartender

Joined: Oct 29, 2001
Posts: 8927
    
    9

Don't sweat it. I'm being short because I'm at work
You write just like you read:

The classes Room and Player must implement the java.io.Serializable interface (there's no methods, just declare them) so the output stream knows they can be written out.
The Java Tutorial has a chapter on Input and Output if you want to know more.
[ March 24, 2006: Message edited by: Joe Ess ]
GregK
Greenhorn

Joined: Oct 24, 2005
Posts: 15
thanks for that. :-)

Now I get the - java.io.NotSerializableException: Room
What does this mean?>

I've already imported Java.io.Serializable and Java.io.*

[ March 24, 2006: Message edited by: Gregory Kodikara ]
[ March 24, 2006: Message edited by: Gregory Kodikara ]
GregK
Greenhorn

Joined: Oct 24, 2005
Posts: 15
Oh god im an idiot
I just realised I hadnt added the 'implements serializable' line to the class names in all classes (I got the same exception for each class)
 
Don't get me started about those stupid light bulbs.
 
subject: Serialisation problem