test of JNI_CreateJavaVM

create.cpp

#include <stdio.h>
#include <stdlib.h>

///
// include JNI and suppress all the warnings it emits
#pragma once
#pragma warning( push )
#pragma warning( suppress : 26451 )
#pragma warning( suppress : 26495 )
#pragma warning( suppress : 26812 )
#include <jni.h>
#pragma warning( pop )

///
// assertion macros

// for things that must always be true or we crash
#define REQUIRED(CON) do { if (CON) break; fprintf(stderr, ("REQUIRED !FAILED! " #CON "\n")); exit(EXIT_FAILURE); } while(false)

// for things that should be true but we can probably continue without
#define EXPECTED(CON) do { if (CON) break; fprintf(stderr, ("EXPECTED ?FAILED? " #CON "\n")); } while(false)


int main(int argc, char* argv[])
{
    printf("Hello World!\n");

    // create and release the JVM several times
	for (int i = 0; i < 5; ++i)
	{
        printf("\n\nstarting loop %d ...\n", i);
		JavaVMInitArgs args = {};
		args.version = JNI_VERSION_1_2;
		
		JavaVMOption options[] = {
			{"-verbose:shutdown",nullptr},
		//	{"-Dibm.java9.forceCommonCleanerShutdown=true",nullptr}
		};
		args.nOptions = sizeof(options) / sizeof(JavaVMOption);
		args.options = options;
		

        JavaVM* jvm;
		JNIEnv* env;

		// create the jvm
		auto create_ret = JNI_CreateJavaVM(&jvm, (void**)&env, &args);
		EXPECTED(JNI_OK == create_ret);

		if (i % 2)
		{
			auto sys = env->FindClass("java/lang/System");
			REQUIRED(sys);
			auto gc = env->GetStaticMethodID(sys, "gc", "()V");
			REQUIRED(gc);
			env->CallStaticVoidMethod(sys, gc);
		}

		// destroy the jvm
		const auto destroy_ret = jvm->DestroyJavaVM();
		EXPECTED(JNI_OK == destroy_ret);

        printf("\n\tloop %d FINISHED\n\n", i);
    }


    return EXIT_SUCCESS;
}

output.txt

λ test
Assuming JAVA_HOME ends with \ and that we're running in a VS Tools prompt ...
C:\Program Files\Semeru\jdk-18.0.2.9-openj9\
Microsoft (R) C/C++ Optimizing Compiler Version 19.35.32217.1 for x64
Copyright (C) Microsoft Corporation.  All rights reserved.

cl : Command line warning D9002 : ignoring unknown option '/lib'
create.cpp
Microsoft (R) Incremental Linker Version 14.35.32217.1
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:create.exe
"C:\Program Files\Semeru\jdk-18.0.2.9-openj9\lib\jvm.lib"
create.obj
Hello World!


starting loop 0 ...
Thread "Common-Cleaner" is still alive after running the shutdown hooks.
EXPECTED ?FAILED? JNI_OK == destroy_ret

        loop 0 FINISHED



starting loop 1 ...
EXPECTED ?FAILED? JNI_OK == create_ret
EXPECTED ?FAILED? JNI_OK == destroy_ret

        loop 1 FINISHED



starting loop 2 ...
EXPECTED ?FAILED? JNI_OK == create_ret
EXPECTED ?FAILED? JNI_OK == destroy_ret

        loop 2 FINISHED



starting loop 3 ...
EXPECTED ?FAILED? JNI_OK == create_ret
EXPECTED ?FAILED? JNI_OK == destroy_ret

        loop 3 FINISHED



starting loop 4 ...
EXPECTED ?FAILED? JNI_OK == create_ret
EXPECTED ?FAILED? JNI_OK == destroy_ret

        loop 4 FINISHED

test.bat

@ECHO OFF

ECHO Assuming JAVA_HOME ends with \ and that we're running in a VS Tools prompt ...
ECHO %JAVA_HOME%

cl /I "%JAVA_HOME%include" /I "%JAVA_HOME%include\win32" /lib "%JAVA_HOME%lib\jvm.lib" create.cpp

CMD /C "SET PATH=%JAVA_HOME%bin\server;%PATH% && create.exe"