Initial implementation of Cronet Async API.

components/cronet/android/cronet_url_request_context.cc

+// Copyright 2014 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.
+
+#include "components/cronet/android/cronet_url_request_context.h"
+
+#include <string>
+
+#include "base/android/jni_android.h"
+#include "base/android/jni_string.h"
+#include "base/json/json_reader.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/metrics/statistics_recorder.h"
+#include "base/values.h"
+#include "components/cronet/android/cronet_url_request.h"
+#include "components/cronet/android/cronet_url_request_adapter.h"
+#include "components/cronet/android/cronet_url_request_context_adapter.h"
+#include "components/cronet/url_request_context_config.h"
+#include "jni/CronetUrlRequestContext_jni.h"
+
+namespace {

[mmenke, 2014/11/06 17:31:29]

nit:  Suggest moving this into the cronet namespace.  Admittedly, only saves one
"cronet::", but if we add more stuff, will probably be more useful.

[mef, 2014/11/06 22:51:46]

Done.

+
+void initJavaNetworkThread(
+    const base::android::ScopedJavaGlobalRef<jobject>& jowner) {

[mmenke, 2014/11/06 17:31:28]

Need to include the header for ScopedJavaGlobalRef

[mef, 2014/11/06 22:51:46]

Done.

+  JNIEnv* jenv = base::android::AttachCurrentThread();
+  cronet::Java_CronetUrlRequestContext_initNetworkThread(jenv, jowner.obj());
+}
+
+}  // namespace
+
+namespace cronet {
+
+// Explicitly register static JNI functions.
+bool CronetUrlRequestContextRegisterJni(JNIEnv* jenv) {

[mmenke, 2014/11/06 17:31:28]

Per comments elsewhere, this is called env pretty universally elsewhere - and is
rather different from jobjects/jstrings - those are references to java
variables, while this is the current thread's Java environment.

[mef, 2014/11/06 22:51:46]

Done.

+  return RegisterNativesImpl(jenv);
+}
+
+// Sets global user-agent to be used for all subsequent requests.
+static jlong CreateRequestContextAdapter(JNIEnv* jenv,
+                                         jobject jcaller,

[mmenke, 2014/11/06 17:31:28]

optional:  Should we use something more meaningful than jcaller, here and in
cronet_url_request?  Like jurl_[cronet_]request_context / jurl_request?  A bit
more wordy, but a bit clearer than "caller".  Same goes for jowner as well.

[mef, 2014/11/06 22:51:46]

Acknowledged. I think those are sufficiently generic boilerplate not to deserve
unique names.

+                                         jobject japp_context,
+                                         jstring jconfig) {
+  std::string config_string =
+      base::android::ConvertJavaStringToUTF8(jenv, jconfig);
+
+  scoped_ptr<base::Value> config_value(base::JSONReader::Read(config_string));
+  if (!config_value || !config_value->IsType(base::Value::TYPE_DICTIONARY)) {
+    DLOG(ERROR) << "Bad JSON: " << config_string;
+    return 0;
+  }
+
+  scoped_ptr<URLRequestContextConfig> context_config(
+      new URLRequestContextConfig());
+  base::JSONValueConverter<URLRequestContextConfig> converter;

[mmenke, 2014/11/06 17:31:28]

Should probably include the JSONValueConverter header, though admittedly,
url_request_context_config.h does as well.

[mef, 2014/11/06 22:51:45]

Done. Moved conversion from JSON into URLRequestContextConfig::LoadFromJSON().

+  if (!converter.Convert(*config_value, context_config.get())) {
+    DLOG(ERROR) << "Bad Config: " << config_value;
+    return 0;
+  }
+
+  // Set application context.
+  base::android::ScopedJavaLocalRef<jobject> scoped_context(jenv, japp_context);
+  base::android::InitApplicationContext(jenv, scoped_context);
+
+  base::android::ScopedJavaGlobalRef<jobject> jcaller_ref;
+  jcaller_ref.Reset(jenv, jcaller);
+
+  CronetURLRequestContextAdapter* context_adapter =
+      new CronetURLRequestContextAdapter();
+  base::Closure init_java_network_thread = base::Bind(&initJavaNetworkThread,
+                                                      jcaller_ref);
+  context_adapter->Initialize(context_config.Pass(), init_java_network_thread);
+
+  return reinterpret_cast<jlong>(context_adapter);
+}
+
+// Destroys native objects.
+static void DestroyRequestContextAdapter(JNIEnv* jenv,
+                                         jobject jcaller,
+                                         jlong jurl_request_context_adapter) {
+  if (jurl_request_context_adapter == 0)

[mmenke, 2014/11/06 17:31:28]

DCHECK(jurl_request_context_adapter);?  For thread safety reasons, we have to
prevent two destroys at once Java-side, so this should never happen.

[mef, 2014/11/06 22:51:46]

Done.

+    return;
+  CronetURLRequestContextAdapter* context_adapter =
+      reinterpret_cast<CronetURLRequestContextAdapter*>(
+          jurl_request_context_adapter);
+  context_adapter->Destroy();
+}
+
+// Starts recording statistics.
+static void InitializeStatistics(JNIEnv* jenv, jobject jcaller) {
+  base::StatisticsRecorder::Initialize();
+}
+
+// Gets current statistics with |filter| as a substring as JSON text (an empty
+// |filter| will include all registered histograms).
+static jstring GetStatisticsJSON(JNIEnv* jenv,
+                                 jobject jcaller,
+                                 jstring jfilter) {
+  std::string query = base::android::ConvertJavaStringToUTF8(jenv, jfilter);
+  std::string json = base::StatisticsRecorder::ToJSON(query);
+  return base::android::ConvertUTF8ToJavaString(jenv, json).Release();

[mmenke, 2014/11/06 17:31:28]

I don't think this should be a method on the context, since it doesn't gather
data just for one context - think it makes sense in its own C++/Java file, with
any other global methods we want to expose.

[mef, 2014/11/06 22:51:46]

Done.

+}
+
+// Starts recording NetLog into file with |fileName|.
+static void StartNetLogToFile(JNIEnv* jenv,
+                              jobject jcaller,
+                              jlong jurl_request_context_adapter,
+                              jstring fileName) {

[xunjieli, 2014/11/06 17:02:36]

nit: fileName -> jfile_name.

[mef, 2014/11/06 22:51:46]

Done.

+  if (jurl_request_context_adapter == 0)
+    return;
+  CronetURLRequestContextAdapter* context_adapter =
+      reinterpret_cast<CronetURLRequestContextAdapter*>(
+          jurl_request_context_adapter);
+  std::string file_name =
+      base::android::ConvertJavaStringToUTF8(jenv, fileName);
+  context_adapter->StartNetLogToFile(file_name);
+}
+
+// Stops recording NetLog.
+static void StopNetLog(JNIEnv* jenv,
+                       jobject jcaller,
+                       jlong jurl_request_context_adapter) {
+  if (jurl_request_context_adapter == 0)
+    return;
+  CronetURLRequestContextAdapter* context_adapter =
+      reinterpret_cast<CronetURLRequestContextAdapter*>(
+          jurl_request_context_adapter);
+  context_adapter->StopNetLog();
+}
+
+static jint SetMinLogLevel(JNIEnv* env, jobject jcaller, jint jlog_level) {
+  jint old_log_level = static_cast<jint>(logging::GetMinLogLevel());
+  // MinLogLevel is global, shared by all URLRequestContexts.
+  logging::SetMinLogLevel(static_cast<int>(jlog_level));
+  return old_log_level;
+}
+
+}  // namespace cronet