For what it's worth, I read your code when you first posted it - but I still don't know what the problem is, exactly, so I stayed out of this thread until now.
The single-most clear piece in your first post was this...
another possibility might be due to the parameter (-n 0) I've passed into the Java would caught the whole process can launch but not responding.
Meant, I tried Java without parameter, it worked! Now we have a bug.
So if you had no problems without the "-n 0", but are now running into problems -with- the "-n 0".. then what is that "-n 0" supposed to do? As far as I know, the arguments after the jar file specification are what are passed to the main class defined in the jar file. Which means "-n 0" is specific to your "MidiInDump.jar".. so how should we know whether it's doing what it's supposed to - we don't have that file.
And unless they can read minds at StackOverflow, I'd say good luck there..
But then again.. in a second StackOverflow post...
...it seems that suddenly, everything is working just fine, despite there being no change in the code (compared to that in this thread), and the question is suddenly about some xSocket unrelated-to-NSIS stuff.
I'm sure we're all happy to help you... but neither your posts nor your code make particularly clear what the problem appears to be (and the follow-up posts really just confuse me even more). I realize that English may not be your first language - so just for kicks, describe the problem in your native language and run it through translate.google.com ; it might still make no sense to us, or it might give us another clue as to what it is you're trying to say.