Java, let CookieHandler work on only one instance

Question

I don't know how CookieHandler works system wide, I did view the source of CookieHandler but found no more information except the get/set methods. Where do TCP/HTTP connections use instance of CookieHandler, which I set by

CookieHandler.setDefault(...)

Which source file I should refer to? URLConnection & HttpURLConnection don't seem have things to do with it.

Help, thanks in advance.

Edit: Is it possible to apply CookieHandler to only one instance in which setDefault is invoked.

I've been wondering the same thing. This [page](http://docs.oracle.com/javase/tutorial/networking/cookies/cookiehandler.html) might hopefully have some info, namely "That is, URLs that use HTTP as the protocol, `new URL("http://example.com")` for example, will use the HTTP protocol handler. This protocol handler calls back to the CookieHander object, if set, to handle the state management." — Tony Chan, Aug 03 '12 at 01:22

score 0 · Answer 1 · answered Apr 11 '12 at 03:11

0

The javadoc for java.net.CookieManager gives a pretty good overview of how CookieHandler fits in.

answered Apr 11 '12 at 03:11

Knut Forkalsrud

1,134
1
7
19

score 0 · Accepted Answer · answered May 15 '14 at 08:27

I got it working by using this

private static class DelegatingCookieManager extends CookieManager {
    @Override public void setCookiePolicy(CookiePolicy cookiePolicy) {
        delegate.get().setCookiePolicy(cookiePolicy);
    }

    @Override public CookieStore getCookieStore() {
        return delegate.get().getCookieStore();
    }

    @Override public Map<String, List<String>> get(
            URI uri, Map<String, List<String>> requestHeaders)
            throws IOException {
        return delegate.get().get(uri, requestHeaders);
    }

    @Override public void put(URI uri, Map<String,
            List<String>> responseHeaders)
            throws IOException {
        delegate.get().put(uri, responseHeaders);
    }
}

which gets installed globally

static {
    CookieHandler.setDefault(new DelegatingCookieManager());
}

but has no state and delegate to a

private static final ThreadLocal<CookieManager> delegate =
     new ThreadLocal<CookieManager>();

which gets instantiated in the class where it gets used

private final CookieManager ownCookieManager = new CookieManager();

like

delegate.set(ownCookieManager);
doRequest();

@user435657 That's probably the way to go. It's that a few of megabytes code feels like too much for parsing and writing a single line (`Cookie`/`Set-Cookie`). — maaartinus, May 19 '14 at 02:12

Java, let CookieHandler work on only one instance

2 Answers2

Linked