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javapathlibrariesunsatisfiedlinkerrorjacob

UnsatisfiedLinkError with JACOB and jre 1.7


I put together a program that uses JACOB to access iTunes ... It works fine in Eclipse but when I export it and run it in the command prompt I get an unsatisfied link error telling me that jacob-1.17-M2-x86.dll is not in my java.library.path.

Ive tried putting it in system32, setting the native library location to its directory...ive tried using the system.setproperties trick...and i couldnt figure out how to use java -d properly

What else can I do? ive been searching the web trying to get this compatible for over 4 hours and nothing seems to work.


Solution

  • I found an amazing post by a sun programmer that fixed my problem!

    public static void addDir(String s) throws IOException {
        try {
            // This enables the java.library.path to be modified at runtime
            // From a Sun engineer at http://forums.sun.com/thread.jspa?threadID=707176
            Field field = ClassLoader.class.getDeclaredField("usr_paths");
            field.setAccessible(true);
            String[] paths = (String[])field.get(null);
            for (int i = 0; i < paths.length; i++) {
                if (s.equals(paths[i])) {
                    return;
                }
            }
            String[] tmp = new String[paths.length+1];
            System.arraycopy(paths,0,tmp,0,paths.length);
            tmp[paths.length] = s;
            field.set(null,tmp);
            System.setProperty("java.library.path", System.getProperty("java.library.path") + File.pathSeparator + s);
        } catch (IllegalAccessException e) {
            throw new IOException("Failed to get permissions to set library path");
        } catch (NoSuchFieldException e) {
            throw new IOException("Failed to get field handle to set library path");
        }
    }
    

    Then I added before my use of the JACOB methods

    addDir("C:" + File.separator + "java" + File.separator + "jre7" + File.separator + "lib")
    

    Worked like a charm.