Is it impossible to run a Java class file that references a .NET assembly linked with ikvmstub using IKVM's java.exe?

[kdaek21]

I created a simple sample C# library as follows:

using System;

public class CSTest {
    public void testFunc() {
        Console.WriteLine("Testing~");
    }
}

Using csc.exe in Visual Studio 2022, I generated CSTest.dll as follows:

csc -t:library CSTest.cs

Then, using IKVM tools, I created Java stub files for both mscorlib.dll and CSTest.dll as shown:

ikvmstub "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\mscorlib.dll" -nostdlib -r "D:\Java\ikvm-jre8-net472\bin\IKVM.Java.dll" -r "D:\Java\ikvm-jre8-net472\bin\IKVM.Runtime.dll" -out mscorlib.jar

ikvmstub CSTest.dll -nostdlib -r "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\mscorlib.dll" -r "D:\Java\ikvm-jre8-net472\bin\IKVM.Java.dll" -r "D:\Java\ikvm-jre8-net472\bin\IKVM.Runtime.dll" -out CSTest.jar

Next, I created and compiled the following Java source code:

import cli.CSTest;

public class CSTestMain {
    public static void main(String[] args) {
        CSTest csTest = new CSTest();
        csTest.testFunc();
    }
}

I compiled the Java source using the following command:

javac -cp .;CSTest.jar;mscorlib.jar CSTestMain.java

Then, I attempted to run it using IKVM's java.exe:

java -cp .;CSTest.jar;mscorlib.jar CSTestMain

However, the following error occurred:

Exception in thread "Thread-0" java.lang.NoClassDefFoundError: cli.CSTest (Could not load file or assembly 'CSTest, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The system cannot find the file specified.)
        at IKVM.Java.Externs.java.lang.ClassLoader.DefineClass(ClassLoader.cs:156)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:772)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:472)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
        at java.security.AccessController.doPrivileged(AccessController.java:310)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:438)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:371)
        at IKVM.Runtime.RuntimeClassLoader.LoadClassImpl(RuntimeClassLoader.cs:631)
        at IKVM.Runtime.RuntimeClassLoader.LoadClass(RuntimeClassLoader.cs:373)
        at IKVM.Runtime.ByteCodeHelper.LoadTypeWrapper(ByteCodeHelper.cs:206)
        at CSTestMain.main(CSTestMain.java:5)

After consulting the IKVM documentation, I used ikvmc to convert CSTestMain.class to a .NET assembly, adjusted the paths and directories, and ran the CSTestMain.exe generated by ikvmc. It worked successfully as follows:

ikvmc CSTestMain.class -target:exe -nostdlib -r:CSTest.dll -r:"C:\Windows\Microsoft.NET\Framework64\v4.0.30319\mscorlib.dll" -runtime:"D:\Java\ikvm-jre8-net472\bin\IKVM.Runtime.dll"

CSTestMain.exe
Testing~

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Question:
Is it impossible to run .NET DLLs linked via Java stubs using IKVM's java.exe?
I even tried adding the path to the DLL in the PATH, but the same error persists.

• IKVM Version: 8.11.1
• .NET Framework Version: 4.7.2

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[wasabii]

Yes.

First, though, the JAR files produced by ikvmstub are just that: stubs. They contain no implementation code. They are only suitable for using javac to compile against.

If you want to add an assembly to the classpath of java.exe, you use -Xreference.