Apache HTTP中的代理链接

Question

有点混淆这里实际可能的东西.

Java Apache HTTP Client(4.x)链代理可以吗？关于如何提示？

我发现文档表明它可以,但源代码有点复杂,我发现至少有一个类(DefaultRequestDirector)抛出异常;

    throw new HttpException("Proxy chains are not supported.")

使用单个代理配置客户端是直接的

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

但对我来说,如何设置代理链并不明显.如果我按照上面文档中的提示操作,请执行以下操作.

    httpClient.setRoutePlanner(new HttpRoutePlanner() {
        @Override
        public HttpRoute determineRoute(HttpHost target, HttpRequest request, HttpContext context) throws HttpException {
            return new HttpRoute(target, null, new HttpHost[]{proxy, new HttpHost("localhost", 8081)}, "https".equalsIgnoreCase(target.getSchemeName()), TunnelType.TUNNELLED, LayerType.PLAIN);
        }
    });

但这会导致上述异常;

org.apache.http.client.ClientProtocolException
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:822)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:754)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:732)
    at Main.main(Main.java:70)
Caused by: org.apache.http.HttpException: Proxy chains are not supported.
    at org.apache.http.impl.client.DefaultRequestDirector.createTunnelToProxy(DefaultRequestDirector.java:957)
    at org.apache.http.impl.client.DefaultRequestDirector.establishRoute(DefaultRequestDirector.java:764)
    at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:579)
    at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:425)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:820)
    ... 8 more

Answer 1

在您上面链接的文档中，它说：

引用 2.7。HttpClient 代理配置 尽管 HttpClient 知道复杂的路由方案和代理链，但它仅支持开箱即用的简单直接或一跳代理连接。取消引用

所以答案是开箱即用的，它无法处理代理链。