Controlling Windows Services from a Java App

[John Davis]

I'm developing a Java Swing App to automate installation and configuration of some Off the shelf products. At a certain point in a product installation, it becomes imperative that I stop a Service (to avoid a file in use problem in another installation).
I am using runtime.exec (see code) to execute various windows installers etc.
Are there commands available which I could execute to exercise control on Windows services?

  
       Runtime rt = Runtime.getRuntime();

       Process proc = rt.exec(completeCommand);
 
       int exitVal = proc.waitFor();

       System.out.println("Process exitValue: " + exitVal);

       String newline = "\n";

       textArea.append("returnCode from Msiexec = " + exitVal ")
 

[David Hibbs]

Have you tried net stop <serviceName>, i.e.

net stop "Crystal Cache Server"

?

[David Hibbs]

To clarify...

"net" is a set of windows network commands:

C:\>net
The syntax of this command is:
NET [ ACCOUNTS | COMPUTER | CONFIG | CONTINUE | FILE | GROUP | HELP |
HELPMSG | LOCALGROUP | NAME | PAUSE | PRINT | SEND | SESSION |
SHARE | START | STATISTICS | STOP | TIME | USE | USER | VIEW ]
C:\>

"net stop" is one of the subcommands (as above).

C:\>net stop
The syntax of this command is:
NET STOP service
C:\>

As you might guess, there is of course a parallel "net start".

[Jean-Francois Briere]

Also you could use the sc command:

import java.io.*;
 
public class NTSvc
{
    public static final int STATE_UNKNOWN       = -1;
    public static final int STATE_STOPPED       = 1;
    public static final int STATE_START_PENDING = 2;
    public static final int STATE_STOP_PENDING  = 3;
    public static final int STATE_RUNNING       = 4;
    
    public int startService(String serviceName)
    throws Exception
    {
        return execServiceController("start", serviceName);
    }
    
    public int stopService(String serviceName)
    throws Exception
    {
        return execServiceController("stop", serviceName);
    }
    
    public int stateService(String serviceName)
    throws Exception
    {
        return execServiceController("query", serviceName);
    }
        
    private int execServiceController(String cmd, String serviceName)
    throws Exception
    {
        final Process proc = Runtime.getRuntime().exec("sc " + cmd + " " + serviceName);
        BufferedReader br = new BufferedReader(new InputStreamReader(proc.getInputStream()));
        String line;
        int state = STATE_UNKNOWN;
        
        while ((line = br.readLine()) != null) // searches for state in the child process output
        {
            int p;
            
            if ((p = line.indexOf(" STATE ")) != -1)
            {
                if ((p = line.indexOf(" : ", p)) != -1)
                    state = Integer.parseInt(line.substring(p + 3, p + 4));
            }
        }
        
        int retCode = proc.waitFor();
        
        if (retCode != 0)
            throw new Exception("Error code of 'sc' is : " + retCode);
        
        return state;
    }
    
    /**
     * Test with 'remote access to registry' service.
     */
    public static void main(String[] args)
    throws Exception
    {
        NTSvc ntSvc = new NTSvc();
        String serviceName = "RemoteRegistry"; // 'remote access to registry' service.
        
        System.out.println("State of service " + serviceName + " = " + ntSvc.stateService(serviceName));
        System.out.println("Starting service " + serviceName + ", state = " + ntSvc.startService(serviceName));
        Thread.sleep(5000);
        System.out.println("State of service " + serviceName + " = " + ntSvc.stateService(serviceName));
        System.out.println("Stopping service " + serviceName + ", state = " + ntSvc.stopService(serviceName));
    }
}

[David Hibbs]

re: sc

Too bad it doesn't exist on my Win2K box:

C:\>sc
'sc' is not recognized as an internal or external command,
operable program or batch file.

[John Davis]

David,

Yes, I noticed that too when I tried it. I don't have an sc command on my Windows XP Home system either.

I am running into problems executing net stop "service name" from my runtime. The process never ends.

I have code to spawn threads to empty error and output streams from the net stop process. These threads never get end of file on their streams
and my main application never gets control back from

 int serviceStopResult = stopServiceProcess.waitFor(); 

Do you have any hints as to what may be going wrong?

Here is the code which sets up and invokes net stop and checks for completion.

try
{
    String[] cmd = new String[4];
    
    cmd[0] = "cmd.exe";
    cmd[1] = " net" ;
    cmd[2] = " stop";
    cmd[3] = " \"IBM MQSeries\"";
    
    System.out.println("Execing " + cmd[0] + " " + 
        cmd[1] + " " + cmd[2] + " "  + cmd[3]);
    
    Runtime stopServiceRT = Runtime.getRuntime();
    
    Process stopServiceProcess = stopServiceRT.exec(cmd);
    
    // any error message?
    
    StreamGobbler errorGobbler = new
    StreamGobbler(stopServiceProcess.getErrorStream(), "ERROR");            
    
    // any output?
    
    StreamGobbler outputGobbler = new
    StreamGobbler(stopServiceProcess.getInputStream(), "OUTPUT");
    
    // kick them off
    
    errorGobbler.start();
    
    outputGobbler.start();
    
    // *******************************************************
    // *  WAIT FOR COMPLETION, DISPLAY THE RESULT
    // *******************************************************
    
    System.out.println("waiting for net stop IBMMQSeries  command to end");
    
    int serviceStopResult = stopServiceProcess.waitFor();
    
    System.out.println("Stop MQ Service exitValue: " + serviceStopResult);
    
    String newline = "\n";
    
    textArea.append("returnCode from stop service = " +
        serviceStopResult + " . . 0 means service is stopped " + newline);
    }
    catch(java.io.IOException ioe)
    {
        System.out.println (ioe.getMessage());
    }
    catch(java.lang.InterruptedException ie)
    {
        System.out.println (ie.getMessage());
    }

[ Jess adjusted the 2nd code block to shrink the whitespace so it wouldn't stretch the screen ]
[ September 23, 2004: Message edited by: Jessica Sant ]

[Jean-Francois Briere]

> Too bad it doesn't exist on my Win2K box:

Yeah, sc.exe comes with the Windows 2000 Prof. Technical Resource Kit.
It also comes with Windows XP Pro.

> Do you have any hints as to what may be going wrong?

You should do:

 
...
 
String[] cmd = new String[5]; // <--- ***
 
cmd[0] = "cmd.exe";
cmd[1] = "/c";  // <--- ***
cmd[2] = "net" ;
cmd[3] = "stop";
cmd[4] = "\"IBM MQSeries\"";
 
...
 

[John Davis]

Jean-Francis,

First of all, thanks a lot for you help.

Actually, I found out what was wrong and everything is running OK now.

The problem is that I (and you apparently) assumed that net is internal to command.com or cmd.exe. The fact is is that it is not a command processor internal. It is some other kind of windows executable (.exe?) and therefore should be invoked in the exec as "net stop \"SERVICE NAME\" "
This works fine, command.com or cmd.exe are not involved.
I also discovered that the command "net stop 'SERVICE NAME' " does not work.
The runtime exec requires double quotes on a command line parameter which has embedded spaces, so the internal double quotes must be escaped.

[Jean-Francois Briere]

> The problem is that I (and you apparently) assumed that net is internal to command.com or cmd.exe.

I didn't assume it. The point I wanted to make is that when using cmd.exe, you must use the "/c" flag. That's all.
For instance, don't do "cmd.exe set" but rather "cmd.exe /c set".

By the way it works perfectly well if you try it with a command-line executable, like net.exe, as I previously wrote.
But you're right, it's overhead to use the cmd shell for any command-line executable.

Cheers