[1.12.2] [IntelliJ] Debugging Vanilla Minecraft

[Cadiboo]

I found out that you can debug Vanilla Minecraft with IntelliJ recently. Heres how

1) Go to the Minecraft Launcher and add -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5009 to your JVM arguments

2) Launch Minecraft normally

3) In IntelliJ go to Run > Attach to Process

4) Select net.minecraft.launchwrapper.Launch

Hope this helps someone

 

 

[Cadiboo]

You are also able to hot-swap code directly into the running program. If you want to you can also change the JVM to use DCEVM (Dynamic Code Evolution VM) for even more advanced hot-swap, but Mojang's default JVM arguments (specifically the -XX:+UseG1GC argument) cause a crash when using this JVM. The final arguments that I use are

-Xms1536M
-Xmx2048M
-XX:+UnlockExperimentalVMOptions
-XX:G1NewSizePercent=20
-XX:G1ReservePercent=20
-XX:MaxGCPauseMillis=50
-XX:G1HeapRegionSize=32M
-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5009

If you are using DCEVM as an alternate JVM add -XXaltjvm=dcevm to the arguments

For more help read community.liferay/blogs/java-classes-instant-reloading-using-dcevm-hotswap-agent and GitHub/DCEVM

Edited November 23, 2018 by Cadiboo

[Cadiboo]

Info on how to do it with eclipse can be found here https://stackoverflow.com/questions/25388758/how-do-i-attach-to-a-process-in-eclipse?rq=1

[Intrepid249]

On 11/23/2018 at 8:43 PM, Cadiboo said:

You are also able to hot-swap code directly into the running program. If you want to you can also change the JVM to use DCEVM (Dynamic Code Evolution VM) for even more advanced hot-swap, but Mojang's default JVM arguments (specifically the -XX:+UseG1GC argument) cause a crash when using this JVM. The final arguments that I use are

-Xms1536M
-Xmx2048M
-XX:+UnlockExperimentalVMOptions
-XX:G1NewSizePercent=20
-XX:G1ReservePercent=20
-XX:MaxGCPauseMillis=50
-XX:G1HeapRegionSize=32M
-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5009

If you are using DCEVM as an alternate JVM add -XXaltjvm=dcevm to the arguments

For more help read community.liferay/blogs/java-classes-instant-reloading-using-dcevm-hotswap-agent and GitHub/DCEVM

 

Is this still valid?

I'm trying it with IntelliJ, and in the settings it's saying that it can't find a valid install of DCEVM... even though I just installed it.

[EDIT: Nevermind, I fixed that problem... it had selected the wrong SDK directory. But it is saying that it "couldn't get dceversion of C:/.../java/jdk1.8.0_211_DCEVM" (the directory I installed it to. Basically made a copy of the JDK directory and selected that as the install location, so that I still had a clean install.)

 

I did notice that the latest version on the DCEVM downloads page was for SDK version 1.8.0_181 however. Is that compatible? I mean, I guess I'll find out if it works or not, but is there a new site for it or something? This post was made about two years ago now...

 

Edited March 16, 2020 by Intrepid249
updated information

[Ugdhar]

1.12 is no longer supported on these forums due to age, this thread is over a year old.

 

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