public class JavaLibraryPathUtil {
	public static void addDir(String dir) throws IOException {
		try {
			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 (dir.equals(paths[i])) {
					return;
				}
			}
			String[] tmp = new String[paths.length+1];
			System.arraycopy(paths, 0, tmp, 0, paths.length);
			tmp[paths.length] = dir;
			field.set(null,tmp);
			System.setProperty("java.library.path", System.getProperty("java.library.path") + File.pathSeparator + dir);
		} 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");
		}
	}

}