Im playing game called Spiral Knights I launch .jar file with this batch command and portable java

CD "App"
"E:\Programy\Portable Apps Platform\PortableApps\CommonFiles\Java64\bin\java.exe" -Xms3G -Xmx3G -XX:+UseParallelGC -XX:+UseParallelOldGC -jar getdown-pro.jar .
exit

My question is does any argument or parameter (or whatever its called) exist to start game window maximized? Not full screen just maximized

I am 2nd hour googling and trying stuff i fond and stuff like

start /max or window=max 

does not work

Im playing game called Spiral Knights I launch .jar file with this batch command and portable java

CD "App"
"E:\Programy\Portable Apps Platform\PortableApps\CommonFiles\Java64\bin\java.exe" -Xms3G -Xmx3G -XX:+UseParallelGC -XX:+UseParallelOldGC -jar getdown-pro.jar .
exit

My question is does any argument or parameter (or whatever its called) exist to start game in maximized window? Not full screen just maximized

I am 2nd hour googling and trying stuff i found and stuff like

start /max or window=max 

does not work

As i understand it all that arguments/parameters like start /max or window=max are going to affect CMD window and not java app and thats why they dont work but all that

-Xms3G -Xmx3G -XX:+UseParallelGC -XX:+UseParallelOldGC

affect java app so is there something like that for window maximized?