#vulnerable code 
                                private boolean hookExist() throws IOException {
        GHRepository ghRepository = getGitHubRepo();
        for (GHHook h : ghRepository.getHooks()) {
            if (!"web".equals(h.getName())) {
                continue;
            }
            if (!getHookUrl().equals(h.getConfig().get("url"))) {
                continue;
            }
            return true;
        }
        return false;
    } 
                            #location 3 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                private boolean hookExist() throws IOException {
        GHRepository ghRepository = getGitHubRepo();
        if (ghRepository == null) {
            throw new IOException("Unable to get repo [ " + reponame + " ]");
        }
        for (GHHook h : ghRepository.getHooks()) {
            if (!"web".equals(h.getName())) {
                continue;
            }
            if (!getHookUrl().equals(h.getConfig().get("url"))) {
                continue;
            }
            return true;
        }
        return false;
    }