13.2.2000
What is the JSL?
Links
Current version
Changes
Will you answer mail asking for support?
Can I contribute or improve JSL?
Requirements
How To start my java programm as a service
Examples
Troublehooting
For experts
License
Contact the author
NT 4.0 and Win2000 are supported.
Supported java version is SUN JDK 1.2.
All varieties of the virtual maschine should work (classic, JIT, HOTSPOT).
I will support future versions of the JDK as soon as they are released.
Currently JDK 1.3 is not supported.
If you would like other JVM supported send me a working example how
to start it using C/C++ code.
By the way: From May 1st I'm open to employment opportunities in
the munich area.
Just in case you need an IT professional with 4 years experience
in consulting, design and implementation of e-business applications and
java development
See here for contact.
Initialization file:
The initialization file is both necessary for setup and running the
service. Don't remove it after you have installed the service.
It contains parameters for both service setup and java application.
[service]
This section is only applied during service installation and removal.
appname =
servicename =
displayname =
stopport = <ip port on which the service manager will signal the
java application to shut down. Must be unique if several jsl services run
on the machine.>
[java]
Changes to this section will take effect when the service is restarted.
params = <number of parameters for the java application. Count start
with param00>
param00 = <java command line parameters>
param01 = ..
Command line options
Calling jsl.exe without parameters gives an overview of the available
options.
-install
Install the service in the NT service manager. Service is not started
immediately, though it will start automatically when NT is rebooted.
Start the service from command line with NET START <APPNAME>.
-remove
Remove an installed service. This may fail if the service is still running.
Stop the service from command line with NET STOP <APPNAME>.
-debug
Run the application from command line for debugging purposes. Service need no be installed.
Stopping a service
To allow for orderly shutdown of the java application the service sends
a signal to the java application by opening a connection on the port specified
as "stopport" in the service ini file.
The most simple way to take advantage of this feature is to use the
ServiceStopper class and Stopable interface as presented in the TelnetEcho
example. The ServiceStopper will only accept connections from the localhost,
so your service cannot be shutdown remotely.
You can avoid implementing the Stopable interface by using the class
SimpleStopper.
This is the most simple service which simple does nothing until stopped.
public static main (String[] argv)
{
ServiceStopper.stop( new SimpleStopper() );
}
If the functionality supplied by ServiceStopper is insufficient for
your needs, you might want to implement your own handler code for stopping
the service. The port is passed to the java application via a -Dservice.stop.port=<PORT>
parameter which is prepended to the parameters given in the INI file. You
can read it back by a call to System.getProperty( "service.stop.port" )
The out put shoud look like this
JSL Java Service launcher by Michael Röschter (Michael@Roeschter.de) Version 0.9 February 6th 2000 Command line options: jsl -install to install the service jsl -remove to remove the service jsl -debug to run as a console app for debugging Initalization file: E:\Java\TEST\jsl_0_9\Debug\jsl.ini appname=Telnet Echo servicename=TelnetEcho displayname=Telnet Echo stopport=8465 param00=-cp param01=e:\java\test\jsl_0_9 param02=TelnetEcho Java command line: java -Dservice.stop.port=8465 -Dservice.path=E:\Java\TEST\jsl_0_9\Debug\ -Dservice.name=TelnetEcho -cp e:\java\test\jsl_0_9 TelnetEcho StartServiceCtrlDispatcher being called. This may take several seconds. Please wait.Now adjust the classpath setting in the initialization file.
Run jsl.exe -debug after you unpacked the distribution package.
Telnet echo will run a primitive telnet server which will simple echo
back any character you try.
Test ist by running your favorite telnet terminal against your localhost.
Now install the service with jsl -install.
Go to the NT service manager and start it up.
Test again and try to shut it down in the service manager.
Uninstall with jsl -remove.
Now nothing should go wrong with your own service.
The service won't start and I can't see why.
Try to start it in debug mode first. Run it as a service only when
you are sure that there are no serious bugs in it.
How can I see may standard output.
You can replace the System.out stream. But that's a hack anyway.
You should use one of the numerous free packages on the web that can
do a comfortable logging to a file.
The program did run fine in debug mode but can't find files when
run as a service
Don't rely on the standard path when locating files from the service.
Always use absolute paths. The service will path it's start path through
a java system property.
How can I find out from which directory the service was started and
how it is named
The JVM is started with a command line similar to this one.
java -Dservice.stop.port=8465 -Dservice.path=E:\Java\TEST\jsl_0_9\Debug\ -Dservice.name=TelnetEcho -cp e:\java\test\jsl_0_9 TelnetEchoThe -D options can be accessed through the System Properties. Look in class java.lang.System for details.
The program did run fine in debug mode but still does not find the
files it needs though I load them from an absolute path.
Drives mounted from a network device are not accessible from a service!
Access them through fully qualified network names.
\\myserver\myfiles\myservice\hello.data
The program did run fine in debug mode but is denied access to the
network shares I need
In standard settings the service will run as a system user. Sytem user
can't access the network. You need to change the security settings manually
in the NT service manager.
There may be other more exotic errors which could result from this.
The service runs fine but I can't stop it. Service manager tells
me the stop request failed and I can't stop it using the task manager.
Services can not be stopped forcedly. They must stop themselves. That's
what the stopable interface is for.
To get rid of your service you must restart NT (after you set service
starting mode to manually).
(If somebody knows a work around please tell me)
This section will explain the source code and give a step by step introduction on how to write a custom java service launcher.
This software is supplied as is. Sources are supplied for informational purposes for the experienced developer.
Please remember that this means: