使用Apache HttpClient通过Web代理进行Java通信失败

我有一个桌面客户端,它将数据发送到Web服务器,我似乎无法通过代理服务器.

更新:尝试通过代理进行通信时,我收到407 HTTP错误.

从我的Web服务器下载信息时,一切都很好.一旦用户配置代理服务器(使用我写的对话框),下载工作正常.但是使用org.apache.http.client.HttpClient上传数据是行不通的.

在从JDialog收集信息后,我正在使用这样的代码配置代理服务器.

        System.setProperty("http.proxyHost", proxyHost);
        System.setProperty("http.proxyPort", "" + portNumber);

现在,一旦我们这样做,简单的下载工作正常.例如,我有从我的Web服务器读取一些xml数据的代码(见下文).在客户的网络上,我的catch块中的错误在配置代理设置之前显示,然后一旦设置了正确的代理,一切正常.

/**
 * Loads a collection of exams from the web site. The URL is determined by
 * configuration or registration since it is State specific.
 */
public static int importExamsWS(StringBuilder msg) {
    try {
        java.net.URL onlineExams = new URL(examURL);
        //Parse the XML data from InputStream and store it.
        return importExams(onlineExams.openStream(), msg);

    } 
    catch (java.net.UnknownHostException noDNS) {
        showError(noDNS, "Unable to connect to proctinator.com to download the exam file.\n"
                + "There is probably a problem with your Internet proxy settings.");
    }
    catch (MalformedURLException | IOException duh) {
        showFileError(duh);
    }
    return 0;
}

但是,当我尝试将数据发送到Web服务器时,就好像忽略了代理设置并抛出了IOException.即:

org.apache.http.conn.HttpHostConnectException: Connection to http://proctinator.com:8080 refused

现在我知道端口8080没有被客户的Web过滤器阻止,因为我们在Web浏览器中测试了该地址.

这是我验证用户输入的注册ID的代码:
 更新:现在我也在这个方法中设置代理.

//Registered is just an enum with ACTIVE, INACTIVE, NOTFOUND, ERROR
public static Registered checkRegistration(int id) throws IOException {    
    httpclient = new DefaultHttpClient();
    Config pref = Config.getConfig(); //stores user-entered proxy settings.
    HttpHost proxy = new HttpHost(pref.getProxyServer(), pref.getProxyPort());
    httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
    URIBuilder builder = new URIBuilder();
    String path = "/Proctorest/rsc/register/" + id;
    try {
        builder.setScheme("http").setHost(server).setPort(8080).setPath(path);
        URI uri = builder.build();
        System.out.println("Connecting to " + uri.toString());
        HttpGet httpget = new HttpGet(uri);
        HttpResponse response = httpclient.execute(httpget);
        System.out.println(response.getStatusLine().toString());
        if(response.getStatusLine().getStatusCode()==200) {
            String msg = EntityUtils.toString(response.getEntity());
            GUI.globalLog.log(Level.INFO, "Server response to checkRegistration(" + id + "): " + msg);
            return Registered.stringToRegistered(msg);
        }
        else {
            GUI.globalLog.log(Level.INFO, "Server response status code to checkRegistration: " + 
                    response.getStatusLine().getStatusCode());
            return Registered.ERROR;
        }
    }
    catch(java.net.URISyntaxException bad) {
        System.out.println("URI construction error: " + bad.toString());
        return Registered.ERROR;
    }
}

我几乎肯定问题来自代理服务器配置,但docs for SystemDefaultHttpClient声称它需要使用http.proxyHost和http.proxyPort的系统属性.我知道属性已正确设置,但我仍然收到此身份验证错误.查看从我的程序生成的日志显示了这个:

checkRegistration INFO: Server response status code to checkRegistration: 407 

如何解决此身份验证错误?

最佳答案
我会开枪.如果代理服务器使用基本身份验证,您可以使用以下代码段作为示例:

DefaultHttpClient httpclient = new DefaultHttpClient();
httpclient.getCredentialsProvider().setCredentials(
    new AuthScope("PROXY HOST", 8080),
    new UsernamePasswordCredentials("username", "password"));

HttpHost targetHost = new HttpHost("TARGET HOST", 443, "https");
HttpHost proxy = new HttpHost("PROXY HOST", 8080);

httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy); 

如果代理服务器正在使用NTLM身份验证,我不认为NTLM支持可用于所有代理服务器版本(它将与某些NTLM身份验证代理服务器版本一起使用 – 检查代理是否使用NTLM身份验证的v1或v2).供参考&解决方法,您可以检查以下内容:

http://hc.apache.org/httpcomponents-client-ga/ntlm.html

http://htmlunit.sourceforge.net/ntlm.html

http://devsac.blogspot.com/2010/10/supoprt-for-ntlmv2-with-apache.html

根据您的代理服务器,您可能需要查看NTCredentials而不是UserPasswordCredentials.

我还建议您可能希望使用wireshark捕获网络数据包并检查代理服务器的响应,以确保导致问题的原因.

转载注明原文:使用Apache HttpClient通过Web代理进行Java通信失败 - 代码日志