对这里实际上可能发生的事情有点困惑。
Java Apache HTTP Client (4.x) 可以链接代理吗?关于如何做的任何提示?
我发现文档表明它可以,但来源有点复杂,我发现至少有一个类 ( DefaultRequestDirector
) 会引发异常;
throw new HttpException("Proxy chains are not supported.")
使用单个代理配置客户端很简单
httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
但对我来说如何设置代理链并不明显。如果我遵循上面文档中的提示,我会执行以下操作。
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