JavaService is an excellent tool for creating server-type Java applications to be run in the background as a Windows NT/2000/XP system service or as Unix daemon process.

JavaService provides an exe(which was developed using JNI and CPP). The core functions like start, stop, kill of webservice were written in that exe(JavaService.exe).

The EXE provide switches to install(JavaService install),start(net start), stop , kill windowsservice service.

Just by providing JVM path, Classpath in the jar file, memory to be allocated to the process we can make Java Application run as WindowsService

Here is it's link JavaService