gistfile1.txt

protected Configuration findExistingConfiguration(ConfigurationAdmin configurationAdmin,
                                                      String pid, String factoryPid) throws IOException, InvalidSyntaxException {
        String filter;
        if (factoryPid == null) {
            filter = "(" + Constants.SERVICE_PID + "=" + pid + ")";
        } else {
            filter = "(" + ConfigurationAdmin.SERVICE_FACTORYPID + "=" + factoryPid + ")";
        }
        Configuration[] configurations = configurationAdmin.listConfigurations(filter);
        if (configurations != null && configurations.length > 0)
        {
            return configurations[0];
        }
        else
        {
            return null;
        }
    }