The Java Native Interface (JNI) - JavaTech: An Introduction to Scientific and Technical Computing with Java - page 596

The result of the command line above is a file named NativeHelloWorld.
obj in the build \ objs directory which must be linked to create a Windows
DLL file.
On a Sun Solaris system, the compilation command line is

cc -c -Ibuild/headers -I$JAVA - HOME/include \
-I$JAVA - HOME/include/sparc \
-obuild/objs/NativeHellowWorld.o \
src/javatech/jni22/NativeHelloWorld.cpp
where we have used the “\ „ continuation character to break the long line into
four lines.

22.3.6 Create a shared library
To create a Windows DLL file, we use the Windows link command line tool,
which is part of the Visual C ++ installation:

link -dll build\objs\NativeHelloWorld.obj
-out:build\NativeHelloWorld.dll

Alternatively, the cl tool can be used to do the linking as follows:

cl -LD build \ objs \ NativeHelloWorld.obj -link
-out:build \ NativeHelloWorld.dll

Both of these commands place the DLL directly into the build directory. The
former also puts the associated but unneeded EXP and LIB files in the build
directory, while the latter puts the EXP and LIB files in the directory from which
it is run.

22.3.7 Run the Java class
The final step is to run the Java class. We start Java in the normal way and specify
the CLASSPATH and the javatech.jni22.JNIHelloWorld class to be run.
We also must tell the operating system where to find the shared library file. In
Windows, the only search path used is PATH ,soitisimportant to add the build
directory (where we created the DLL file) to the PATH environment variable:

set PATH=build;%PATH%
java -classpath build/classes javatech.jni22.JNIHelloWorld

Alternatively, instead of modifying the PATH variable, we can utilize the
java.library.path system property:

java -classpath build/classes -Djava.library.path=build
javatech.jni22.JNIHelloWorld