You need recent Smalltalk/X jv-branch downloaded and installed on your computer. STX:LIBJAVA won't run correctly on official eXept Smalltalk/X distribution downloaded from http://www.exept.de. STX:LIBJAVA is still considered as experimental, work-in-progress and thus it is not yet included in official release.
2. JRE/JDK class filesSTX:LIBJAVA does not provide its own java class library, instead it uses (now open-sourced) class library from OpenJDK. Therefore You need the OpenJDK-based JRE/JDK class files be installed on your system. Class files from ordinary Java installation are just fine. If you have a JRE/JDK already installed on your system, STX:LIBJAVA will automatically use it.
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