[Android] Java Bridge with Gin: implement Java methods invocation

content/browser/renderer_host/java/gin_java_method_invocation_helper.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 "content/browser/renderer_host/java/gin_java_method_invocation_helper.h"
+
+#include <unistd.h>
+
+#include "base/android/event_log.h"
+#include "base/android/jni_android.h"
+#include "base/android/jni_string.h"
+#include "base/float_util.h"
+#include "content/browser/renderer_host/java/gin_java_script_to_java_types_coercion.h"
+#include "content/browser/renderer_host/java/java_method.h"
+#include "content/browser/renderer_host/java/jni_helper.h"
+#include "content/common/android/gin_java_bridge_value.h"
+#include "content/public/browser/browser_thread.h"
+
+using base::android::AttachCurrentThread;
+using base::android::ScopedJavaLocalRef;
+
+namespace content {
+
+namespace {
+
+const char kObjectIsGone[] = "Java object is gone";
+const char kMethodNotFound[] = "Method not found";
+const char kAccessToObjectGetClassIsBlocked[] =
+    "Access to java.lang.Object.getClass is blocked";
+const char kJavaExceptionRaised[] =
+    "Java exception has been raised during method invocation";
+
+// See frameworks/base/core/java/android/webkit/EventLogTags.logtags
+const int kObjectGetClassInvocationAttemptLogTag = 70151;
+
+}  // namespace
+
+GinJavaMethodInvocationHelper::GinJavaMethodInvocationHelper(
+    scoped_ptr<ObjectDelegate> object,
+    const std::string& method_name,
+    const base::ListValue& arguments)
+    : object_(object.Pass()),
+      method_name_(method_name),
+      arguments_(arguments.DeepCopy()) {
+}
+
+GinJavaMethodInvocationHelper::~GinJavaMethodInvocationHelper() {}
+
+void GinJavaMethodInvocationHelper::Init(DispatcherDelegate* dispatcher) {
+  // Build on the UI thread a map of object_id -> WeakRef for Java objects from
+  // |arguments_|.  Then we can use this map on the background thread without
+  // accessing |dispatcher|.
+  BuildObjectRefsFromListValue(dispatcher, arguments_.get());
+}
+
+// As V8ValueConverter has finite recursion depth when serializing
+// JavaScript values, we don't bother about having a recursion threshold here.
+void GinJavaMethodInvocationHelper::BuildObjectRefsFromListValue(
+    DispatcherDelegate* dispatcher,
+    const base::Value* list_value) {
+  DCHECK(list_value->IsType(base::Value::TYPE_LIST));
+  const base::ListValue* list;
+  list_value->GetAsList(&list);
+  for (base::ListValue::const_iterator iter = list->begin();
+       iter != list->end();
+       ++iter) {
+    if (AppendObjectRef(dispatcher, *iter))
+      continue;
+    if ((*iter)->IsType(base::Value::TYPE_LIST)) {
+      BuildObjectRefsFromListValue(dispatcher, *iter);
+    } else if ((*iter)->IsType(base::Value::TYPE_DICTIONARY)) {
+      BuildObjectRefsFromDictionaryValue(dispatcher, *iter);
+    }
+  }
+}
+
+void GinJavaMethodInvocationHelper::BuildObjectRefsFromDictionaryValue(
+    DispatcherDelegate* dispatcher,
+    const base::Value* dict_value) {
+  DCHECK(dict_value->IsType(base::Value::TYPE_DICTIONARY));
+  const base::DictionaryValue* dict;
+  dict_value->GetAsDictionary(&dict);
+  for (base::DictionaryValue::Iterator iter(*dict);
+       !iter.IsAtEnd();
+       iter.Advance()) {
+    if (AppendObjectRef(dispatcher, &iter.value()))
+      continue;
+    if (iter.value().IsType(base::Value::TYPE_LIST)) {
+      BuildObjectRefsFromListValue(dispatcher, &iter.value());
+    } else if (iter.value().IsType(base::Value::TYPE_DICTIONARY)) {
+      BuildObjectRefsFromDictionaryValue(dispatcher, &iter.value());
+    }
+  }
+}
+
+bool GinJavaMethodInvocationHelper::AppendObjectRef(
+    DispatcherDelegate* dispatcher,
+    const base::Value* raw_value) {
+  if (!GinJavaBridgeValue::ContainsGinJavaBridgeValue(raw_value))
+    return false;
+  scoped_ptr<const GinJavaBridgeValue> value(
+      GinJavaBridgeValue::FromValue(raw_value));
+  if (!value->IsType(GinJavaBridgeValue::TYPE_OBJECT_ID))
+    return false;
+  GinJavaBoundObject::ObjectID object_id;
+  if (value->GetAsObjectID(&object_id)) {
+    ObjectRefs::iterator iter = object_refs_.find(object_id);
+    if (iter == object_refs_.end()) {
+      JavaObjectWeakGlobalRef object_ref(
+          dispatcher->GetObjectWeakRef(object_id));
+      if (!object_ref.is_empty()) {
+        object_refs_.insert(std::make_pair(object_id, object_ref));
+      }
+    }
+  }
+  return true;
+}
+
+void GinJavaMethodInvocationHelper::Invoke() {
+  JNIEnv* env = AttachCurrentThread();
+  ScopedJavaLocalRef<jobject> obj(object_->GetLocalRef(env));
+  if (obj.is_null()) {
+    SetInvocationFailure(kObjectIsGone);
+    return;
+  }
+  const JavaMethod* method =
+      object_->FindMethod(method_name_, arguments_->GetSize());
+  if (!method) {
+    SetInvocationFailure(kMethodNotFound);
+    return;
+  }
+
+  if (object_->IsObjectGetClassMethod(method)) {
+    base::android::EventLogWriteInt(kObjectGetClassInvocationAttemptLogTag,
+                                    getuid());
+    SetInvocationFailure(kAccessToObjectGetClassIsBlocked);
+    return;
+  }
+
+  std::vector<jvalue> parameters(method->num_parameters());
+  for (size_t i = 0; i < method->num_parameters(); ++i) {
+    const base::Value* argument;
+    arguments_->Get(i, &argument);
+    parameters[i] = CoerceJavaScriptValueToJavaValue(
+        env, argument, method->parameter_type(i), true, object_refs_);
+  }
+  InvokeMethod(obj.obj(), method->return_type(), method->id(), &parameters[0]);
+
+  // Now that we're done with the jvalue, release any local references created
+  // by CoerceJavaScriptValueToJavaValue().
+  for (size_t i = 0; i < method->num_parameters(); ++i) {
+    ReleaseJavaValueIfRequired(env, &parameters[i], method->parameter_type(i));
+  }
+}
+
+void GinJavaMethodInvocationHelper::SetInvocationFailure(
+    const char* error_message) {
+  holds_primitive_result_ = true;
+  primitive_result_.reset(new base::ListValue());
+  error_message_ = error_message;
+}
+
+void GinJavaMethodInvocationHelper::SetPrimitiveResult(
+    const base::ListValue& result_wrapper) {
+  holds_primitive_result_ = true;
+  primitive_result_.reset(result_wrapper.DeepCopy());
+}
+
+void GinJavaMethodInvocationHelper::SetObjectResult(
+    const base::android::JavaRef<jobject>& object,
+    const base::android::JavaRef<jclass>& safe_annotation_clazz) {
+  holds_primitive_result_ = false;
+  object_result_.Reset(object);
+  safe_annotation_clazz_.Reset(safe_annotation_clazz);
+}
+
+bool GinJavaMethodInvocationHelper::HoldsPrimitiveResult() {
+  return holds_primitive_result_;
+}
+
+const base::ListValue& GinJavaMethodInvocationHelper::GetPrimitiveResult() {
+  return *primitive_result_.get();
+}
+
+const base::android::JavaRef<jobject>&
+GinJavaMethodInvocationHelper::GetObjectResult() {
+  return object_result_;
+}
+
+const base::android::JavaRef<jclass>&
+GinJavaMethodInvocationHelper::GetSafeAnnotationClass() {
+  return safe_annotation_clazz_;
+}
+
+const std::string& GinJavaMethodInvocationHelper::GetErrorMessage() {
+  return error_message_;
+}
+
+void GinJavaMethodInvocationHelper::InvokeMethod(jobject object,
+                                                 const JavaType& return_type,
+                                                 jmethodID id,
+                                                 jvalue* parameters) {
+  JNIEnv* env = AttachCurrentThread();
+  base::ListValue result_wrapper;
+  switch (return_type.type) {
+    case JavaType::TypeBoolean:
+      result_wrapper.AppendBoolean(
+          env->CallBooleanMethodA(object, id, parameters));
+      break;
+    case JavaType::TypeByte:
+      result_wrapper.AppendInteger(
+          env->CallByteMethodA(object, id, parameters));
+      break;
+    case JavaType::TypeChar:
+      result_wrapper.AppendInteger(
+          env->CallCharMethodA(object, id, parameters));
+      break;
+    case JavaType::TypeShort:
+      result_wrapper.AppendInteger(
+          env->CallShortMethodA(object, id, parameters));
+      break;
+    case JavaType::TypeInt:
+      result_wrapper.AppendInteger(
+          env->CallIntMethodA(object, id, parameters));
+      break;
+    case JavaType::TypeLong:
+      result_wrapper.AppendDouble(
+          env->CallLongMethodA(object, id, parameters));
+      break;
+    case JavaType::TypeFloat: {
+      float result = env->CallFloatMethodA(object, id, parameters);
+      if (base::IsFinite(result)) {
+        result_wrapper.AppendDouble(result);
+      } else {
+        result_wrapper.Append(
+            GinJavaBridgeValue::CreateNonFiniteValue(result).release());
+      }
+      break;
+    }
+    case JavaType::TypeDouble: {
+      double result = env->CallDoubleMethodA(object, id, parameters);
+      if (base::IsFinite(result)) {
+        result_wrapper.AppendDouble(result);
+      } else {
+        result_wrapper.Append(
+            GinJavaBridgeValue::CreateNonFiniteValue(result).release());
+      }
+      break;
+    }
+    case JavaType::TypeVoid:
+      env->CallVoidMethodA(object, id, parameters);
+      result_wrapper.Append(
+          GinJavaBridgeValue::CreateUndefinedValue().release());
+      break;
+    case JavaType::TypeArray:
+      // LIVECONNECT_COMPLIANCE: Existing behavior is to not call methods that
+      // return arrays. Spec requires calling the method and converting the
+      // result to a JavaScript array.
+      result_wrapper.Append(
+          GinJavaBridgeValue::CreateUndefinedValue().release());
+      break;
+    case JavaType::TypeString: {
+      jstring java_string = static_cast<jstring>(
+          env->CallObjectMethodA(object, id, parameters));
+      // If an exception was raised, we must clear it before calling most JNI
+      // methods. ScopedJavaLocalRef is liable to make such calls, so we test
+      // first.
+      if (base::android::ClearException(env)) {
+        SetInvocationFailure(kJavaExceptionRaised);
+        return;
+      }
+      ScopedJavaLocalRef<jstring> scoped_java_string(env, java_string);
+      if (!scoped_java_string.obj()) {
+        // LIVECONNECT_COMPLIANCE: Existing behavior is to return undefined.
+        // Spec requires returning a null string.
+        result_wrapper.Append(
+            GinJavaBridgeValue::CreateUndefinedValue().release());
+        break;
+      }
+      result_wrapper.AppendString(
+          base::android::ConvertJavaStringToUTF8(scoped_java_string));
+      break;
+    }
+    case JavaType::TypeObject: {
+      // If an exception was raised, we must clear it before calling most JNI
+      // methods. ScopedJavaLocalRef is liable to make such calls, so we test
+      // first.
+      jobject java_object = env->CallObjectMethodA(object, id, parameters);
+      if (base::android::ClearException(env)) {
+        SetInvocationFailure(kJavaExceptionRaised);
+        return;
+      }
+      ScopedJavaLocalRef<jobject> scoped_java_object(env, java_object);
+      if (!scoped_java_object.obj()) {
+        result_wrapper.Append(base::Value::CreateNullValue());
+        break;
+      }
+      SetObjectResult(scoped_java_object, object_->GetSafeAnnotationClass());
+      return;
+    }
+  }
+  // This is for all cases except JavaType::TypeObject.
+  if (!base::android::ClearException(env)) {
+    SetPrimitiveResult(result_wrapper);
+  } else {
+    SetInvocationFailure(kJavaExceptionRaised);
+  }
+}
+
+}  // namespace content