Javaws, classpath, and OpenOffice client-side resources

Question

I've developed an application on top of OpenOffice which uses the installed openoffice jars and .dll's. I can't get the dll's to load using javaws. My root problem seems to be a non-standard way that openoffice is trying to load system libraries - from the OpenOffice forums, they use the location of a jar and then "go up one directory". My app works fine when I can provide control over the classpath (for example, from a batch file, ant, or eclipse) but I am stuck trying to webstart. The OpenOffice community has no answers.
I've tried a huge number of permutations of things, based on advice from this forum:
-- jar'ing up the installation jars and deploying them (works for the OpenOffice java classes, but not for the DLL loads)
-- creating a custom class loader (again, works to load the java classes but not the DLL's)
-- jar'ing up the installation DLL's and deploying them (doesn't have any effect)
-- setting the system classpath in my code to the known client-side location of the installation (doesn't work - get NoClassDefFoundError)
String cp = System.getProperty("java.class.path");
String newcp = cp + System.getProperty("path.separator") +
              "C:\Program Files\OpenOffice.org1.1.4\program\classes";
System.setProperty("java.class.path", newcp);I would have thought the last attempt would have worked - I don't understand why the classes cannot be found. Does anyone have any positive experiences with manipulating classpath via javaws?
Thanks,
Dave Santo

Answer 1

I've solved this issue.
I had to create a shell application, launched via jnlp. The shell app grabs the webstart cached jar files, builds a classpath string with all these jars and the client-side OpenOffice installation location, and launches the real application, i.e.
public static void main(String[] args)
    File tmpdir = new File(System.getProperty("java.io.tmpdir"));
    // build the constructedClasspathString, based on this class (see thread referenced below)
    String[] launchArgs = new String[4];  // or more if you want to copy in other arguments
    launchArg[0] = "java";
    launchArg[1] = "-cp";
    launchArg[2] = constructedClasspathString;
    launchArg[3] = targetClassNameString;
    // copy in other arguments as desired...
    Process p = Runtime.getRuntime().exec(launchArg, null, tmpdir);
    StreamGobbler out = new StreamGobbler(p.getInputStream(), "OUT");
    out.start();
    StreamGobbler err = new StreamGobbler(p.getErrorStream(), "ERR");
    err.start;
    int result = p.waitFor();
}You definitely want to inherit this instance's environment, so don't override the 2nd argument to exec().
The StreamGobbler stuff can be found here:
http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html
The 'grabbing the webstart cached jar files' stuff can be found here (you'll want to modify it a little ...)
http://forum.java.sun.com/thread.jspa?forumID=38&threadID=71208
- Dave