How to use Tor combine with Java [closed]

Question

Updated my question

I'm building a crawler system by Java to compare price online. However, I worry about my IP address can be banned. So I intend to use proxy to change IP dynamic or use some tools to rotate IP automatically.

Many people said that TOR is a powerful tool to rotate IP. However, I don't know how to use Tor and how to integrate Tor to Java Web Application ?

I've search Google to find example but still find nothing useful.

Anyone can help me.

Dioptase

There are either too many possible answers, or good answers would be too long for this format. Please add details to narrow the answer set or to isolate an issue that can be answered in a few paragraphs. – Fokos

Hi @RGraham, I appreciate your comment. I've updated my question. Can you help me ? – Dioptase

Why close this question? for me is useful. – Orlov

Answer 1

You'll just need to get Java to use the SOCKS4 proxy at localhost:8118 (8118 is the default Tor port) when it makes an outgoing HTTP connection that uses a URL (use URLConnection), while the Tor service is running. See here for how to use proxies in Java 8.

Edit: there is also this pure Java Tor library that you may be able to use, either directly or through minor modification (if it acts entirely like the normal native Tor service), but it hasn't been updated in a while so may not be compatible with the latest Tor specification.

HttpClient example:

HttpHost proxy = new HttpHost("127.0.0.1", 8118, "http");

DefaultHttpClient httpclient = new DefaultHttpClient();
try {
    httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);

    HttpHost target = new HttpHost("www.google.com", 80, "http");
    HttpGet req = new HttpGet("/");

    System.out.println("executing request to " + target + " via " + proxy);
    HttpResponse rsp = httpclient.execute(target, req);
    ...
} finally {
    // When HttpClient instance is no longer needed,
    // shut down the connection manager to ensure
    // immediate deallocation of all system resources
    httpclient.getConnectionManager().shutdown();
}

Note that you must have the Tor service running for this.

Danseur

Please tick my answer as the best answer if it helped you :) – Danseur

Hi @Chris Dennett, may I use Tor with HttpClient (instead of URLConnection) because I want to run multiple threads ? – Dioptase

Sure, see this question/answer: https://mcmap.net/q/543389/-common-httpclient-and-proxy – Danseur

Your answer will be the best if you give me some example by integrating Tor and HttpClient in Java, please. Thanks so much @Chris Dennett – Dioptase

How can I start Tor service ? I just find how to install Tor Browser on Linux (torproject.org/projects/torbrowser.html.en) – Dioptase

It should come with a command named tor that is installed when you install Tor Browser on Linux. You should have the user start this, or start it from within Java. Use new ProcessBuilder("path_to_tor","param1","param2").start(); and it should run in the background, ready to accept connections (parameters are probably not needed, but included just in case) – Danseur

Try which tor to see where it's been installed to, if it's locatable within PATH (it's always a good idea to specify the path when possible). Alternatively, try find / -name tor. – Danseur

I've tried Orchid and it came up that it does not supports fetching HTTP pages: com.subgraph.orchid.TorException: Returning HTTP page not implemented at com.subgraph.orchid.socks.SocksClientTask.sendHttpPage(SocksClientTask.java:112) I understand that it's not because it does not support HTTP in general, but that it not exposes HTTP proxy but SOCKS proxy? So I still should try with forwarding apache httpclient through socks proxy – Longheaded

IDK Why on earth this non-working answer was accepted ! tor is NOT HTTP Proxy!! – Kerri

You're talking about the difference between SOCKS and HTTP proxy? It's not that far away, just use this: #22938483. Tor can use either, but SOCKS is probably recommended. – Danseur