Make URLRequestThrottlerManager a member of URLRequestContext.

net/url_request/url_request_throttler_manager.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_URL_REQUEST_URL_REQUEST_THROTTLER_MANAGER_H_
 #define NET_URL_REQUEST_URL_REQUEST_THROTTLER_MANAGER_H_
 #pragma once
 
 #include <map>
 #include <set>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/memory/singleton.h"
 #include "base/threading/non_thread_safe.h"
 #include "base/threading/platform_thread.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/net_export.h"
 #include "net/base/network_change_notifier.h"
 #include "net/url_request/url_request_throttler_entry.h"
 
 namespace net {
 
 class BoundNetLog;
 class NetLog;
 
 // Class that registers URL request throttler entries for URLs being accessed
 // in order to supervise traffic. URL requests for HTTP contents should
 // register their URLs in this manager on each request.
 //
 // URLRequestThrottlerManager maintains a map of URL IDs to URL request
 // throttler entries. It creates URL request throttler entries when new URLs
 // are registered, and does garbage collection from time to time in order to
 // clean out outdated entries. URL ID consists of lowercased scheme, host, port
 // and path. All URLs converted to the same ID will share the same entry.
-//
-// NOTE: All usage of this singleton object must be on the same thread,
-// although to allow it to be used as a singleton, construction and destruction
-// can occur on a separate thread.
 class NET_EXPORT URLRequestThrottlerManager
     : NON_EXPORTED_BASE(public base::NonThreadSafe),
       public NetworkChangeNotifier::IPAddressObserver,
       public NetworkChangeNotifier::OnlineStateObserver {
  public:
-  static URLRequestThrottlerManager* GetInstance();
+  URLRequestThrottlerManager();
+  virtual ~URLRequestThrottlerManager();
 
   // Must be called for every request, returns the URL request throttler entry
   // associated with the URL. The caller must inform this entry of some events.
   // Please refer to url_request_throttler_entry_interface.h for further
   // informations.
   scoped_refptr<URLRequestThrottlerEntryInterface> RegisterRequestUrl(
       const GURL& url);
 
   // Adds the given host to a list of sites for which exponential back-off
   // throttling will be disabled.  Subdomains are not included, so they
@@ skipping 24 matching lines @@
   // Sets the NetLog instance to use.
   void set_net_log(NetLog* net_log);
   NetLog* net_log() const;
 
   // IPAddressObserver interface.
   virtual void OnIPAddressChanged() OVERRIDE;
 
   // OnlineStateObserver interface.
   virtual void OnOnlineStateChanged(bool online) OVERRIDE;
 
- protected:
-  URLRequestThrottlerManager();
-  virtual ~URLRequestThrottlerManager();
-
   // Method that allows us to transform a URL into an ID that can be used in our
   // map. Resulting IDs will be lowercase and consist of the scheme, host, port
   // and path (without query string, fragment, etc.).
   // If the URL is invalid, the invalid spec will be returned, without any
   // transformation.
   std::string GetIdFromUrl(const GURL& url) const;
 
   // Method that ensures the map gets cleaned from time to time. The period at
   // which garbage collecting happens is adjustable with the
   // kRequestBetweenCollecting constant.
   void GarbageCollectEntriesIfNecessary();
 
   // Method that does the actual work of garbage collecting.
   void GarbageCollectEntries();
 
   // When we switch from online to offline or change IP addresses, we
   // clear all back-off history. This is a precaution in case the change in
   // online state now lets us communicate without error with servers that
   // we were previously getting 500 or 503 responses from (perhaps the
   // responses are from a badly-written proxy that should have returned a
   // 502 or 504 because it's upstream connection was down or it had no route
   // to the server).
   void OnNetworkChange();
 
   // Used by tests.
   int GetNumberOfEntriesForTests() const { return url_entries_.size(); }
 
  private:
-  friend struct DefaultSingletonTraits<URLRequestThrottlerManager>;
-
   // From each URL we generate an ID composed of the scheme, host, port and path
   // that allows us to uniquely map an entry to it.
   typedef std::map<std::string, scoped_refptr<URLRequestThrottlerEntry> >
       UrlEntryMap;
 
   // We maintain a set of hosts that have opted out of exponential
   // back-off throttling.
   typedef std::set<std::string> OptOutHosts;
 
   // Maximum number of entries that we are willing to collect in our map.
@@ skipping 36 matching lines @@
 
   // Valid once we've registered for network notifications.
   base::PlatformThreadId registered_from_thread_;
 
   DISALLOW_COPY_AND_ASSIGN(URLRequestThrottlerManager);
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_THROTTLER_MANAGER_H_