Java Httpclient org.apache.http.client.methods.HttpPut 出现 404 错误

Question

我在我的系统属性中设置了代理。在我的 java 应用程序中，使用 Apache HttpClient 将文件 HttpPut 到 URL，代码如下。我尝试创建客户端的所有 3 种方法都返回 404。当我没有代理设置时，这同样适用于 HttpClients.getDefault()。我该如何解决？感谢你的帮助。谢谢

 public void sendHTTPPutRequest(@NotNull HttpPut req)
            throws DataExtractException {
        try (CloseableHttpClient client = buildClient(req.getURI());
                CloseableHttpResponse response = client.execute(req)) {
           // ........
            }
    }

 private CloseableHttpClient buildClient(URI uri) {
    Proxy firstProxy = ProxySelector.getDefault().select(uri).get(0);        
    InetSocketAddress proxyAddress = (InetSocketAddress) firstProxy.address();
    HttpHost proxy = (proxyAddress == null || firstProxy.equals(Proxy.NO_PROXY)) ? null
            : new HttpHost(proxyAddress.getHostName(), proxyAddress.getPort());
    BasicCookieStore cookieStore = new BasicCookieStore();
    return HttpClients.custom().setDefaultCookieStore(cookieStore).setProxy(proxy).build();

    // NOTE: Here I also tried HttpClients.createSystem(), and HttpClients.getDefault()
    //  all 3 clients returned 404.

}