Startup Issue with Minecraft - Java version not compatible with Minecraft versions higher than 1.20.4

[Kawel]

System Information

Field	Value
Operating System	Linux - Debian GNU/Linux 11 on x86_64
Product	AMP ‘Callisto’ v2.5.0.14 (Mainline)
Virtualization	QEMU_KVM
Application	Minecraft
Module	MinecraftModule
Running in Container	No
Current State	Sleeping

Problem Description

Issue

The error code given in red text is:

java.lang.RuntimeException: Error invoking MC server bundler: java.lang.UnsupportedClassVersionError: net/minecraft/bundler/Main has been compiled by a more recent version of the Java Runtime (class file version 65.0), this version of the Java Runtime only recognizes class file versions up to 61.0

I can’t seem to be able to start any server type above the specified version. From my understanding, the JDK needs to be updated but I could not find any way to update it from my side. The Java version is already set to the highest available in the settings.

Reproduction Steps

• Start a new Instance
• Update and start Server
• Accept EULA and stop the server after first run
• Set the version to any version higher than 1.20.4 (1.21 in this case)
• Update and restart server
• Server doesn’t start and gives the Error code attached in the detailed description

[ThePotatoKing]

1.20.6 and newer need Java 21 to be selected.
Since you’re not running in docker you’ll need to install it via your system’s package manager

[Kawel]

The newest version of Java available in the drop down menu is “Java 17 (openjdk)”. Im using Hostinger, if that helps. I do know how to operate Debian but I don’t think I have admin access to the console.

[ThePotatoKing]

This is not Hostinger support, this is the forum for AMP. (Hostinger doesn’t set the support URL in their settings, so it defaults to here)
You should have access to the Debian command line, but if not, you’ll need to contact Hostinger’s support through their site.

[Kawel]

I guessed as much, thank you for the input anyway.