How can I compile a java code inside of unreal?

Development Programming & Scripting Blueprint
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I am trying to make a java ide using Ue5.
I have almost completed the project but I don’t know how to compile and run the java program.
I know the cmd commands for this job but can I do this without using CMD as the game will hang during the compilation and the execution.
*I just install the new JDK “corretto-18.0.1” it does not require to use javac.
going to the java bin directory
then java <then the file directory>
but I want to execute 3 commands in the same cmd How can I do it.

  1. cd/
    2 . cd <location of the jdk>3. java <then the file directory>
2

Here’s how you can run multiple Java-related commands without hanging UE5 or relying too much on CMD:

Since CMD interrupts the game thread when called directly from UE5, your best bet is to use asynchronous process management with CreateProc in Unreal Engine (C++) or System.Diagnostics.Process if you’re bridging via .NET.

If you’re sticking with raw CMD calls temporarily, here’s how to chain those commands in one line:

cmd /c "cd C:\path\to\jdk\bin && java C:\path\to\YourFile.java"

Or if your .java file isn’t pre-compiled:

cmd /c "cd C:\path\to\jdk\bin && javac C:\path\to\YourFile.java && java YourFile"

Replace paths as needed.

To avoid freezing the UE5 game during execution:

  • Use AsyncTask or FRunnable for background execution

  • Capture stdout/stderr to a log file or in-game console

  • Keep your JDK path environment variable clean to avoid javac/java mismatch

If you’re doing this as a learning project or for portfolio-building, you might like the Java Full Stack Developer course at Visible Campus, Bangalore — they help you go beyond theory with real-world integration projects (Java + frontend + cloud dev). One of my batchmates actually built a Java-based code editor for learning modules!