Help Community command error

[0flee]

Hello folks, Today i decide to do something interesting. I want to add on community board when player have subclass, to display there.
and the code it is like that.

returnHtml = returnHtml.replace("%subclass%", ClassListData.getInstance().getClass(player.getSubClasses().get(1).getClassId()).getClientCode());

All good untill now, but when player doesn`t have subclass, he can't open cb and i get error on gameserver:
https://ibb.co/FKz1Hkx
Can someone tell me how and where i can add !=null ?

Pack: L2jMobius
Greetings !!

Edited February 15, 2021 by 0flee

[Kara]

1 hour ago, 0flee said:

Hello folks, Today i decide to do something interesting. I want to add on community board when player have subclass, to display there.
and the code it is like that.

returnHtml = returnHtml.replace("%subclass%", ClassListData.getInstance().getClass(player.getSubClasses().get(1).getClassId()).getClientCode());

All good untill now, but when player doesn`t have subclass, he can't open cb and i get error on gameserver:
https://ibb.co/FKz1Hkx
Can someone tell me how and where i can add !=null ?

Pack: L2jMobius
Greetings !!

 

Hi. There are million ways to solve this including streams or fix the getClass() method and send only player.getSubClasses() but the easiest way to do that is by doing a check before that if player has any subclass then do what you do else replace with "-" 

 

So kinda like this:

 

returnHtml = returnHtml.replace("%subclass%", player.getSubClasses().size() > 0 ? ClassListData.getInstance().getClass(player.getSubClasses().get(1).getClassId()).getClientCode() : "-");

 

 

[0flee]

How i can find the value of .size()

[Pleyne]

14 minutes ago, 0flee said:

How i can find the value of .size()

By debugging. If you don't know how to debug in 2021 that will be a hard time for you developing (I'm not saying you don't know how to, you might know how to, though you would have solved this issue in 15sec if you did debugging).

The code above from Kara gave you everything to be fixed, why do you need to know exact size? command ".size()" calculates elements in collection (and function 'getSubClasses' return the collection, so the logic is get subs collection > calculate size). The value for different players with different subclasses amount will be different. 

About image you gave: NullPointer error means that you're trying to reach things that are not initialized or set. Always check if object exists before trying to take its actual value (would recommend reading a bit about that, it's the easiest to fix problem and you will face it a lot if you will continue on learning developing).
 

[0flee]

19 hours ago, Kara said:

 

Hi. There are million ways to solve this including streams or fix the getClass() method and send only player.getSubClasses() but the easiest way to do that is by doing a check before that if player has any subclass then do what you do else replace with "-" 

 

So kinda like this:

 

returnHtml = returnHtml.replace("%subclass%", player.getSubClasses().size() > 0 ? ClassListData.getInstance().getClass(player.getSubClasses().get(1).getClassId()).getClientCode() : "-");

 

 

Best answer. Fixed, can close topic. Thank you !

[Kara]

1 hour ago, 0flee said:

Best answer. Fixed, can close topic. Thank you !

 

[Vision]

3 hours ago, 0flee said:

Best answer. Fixed, can close topic. Thank you !

 

Ok locked.