Adds the renderer component of the Java Bridge

content/renderer/java_bridge_dispatcher.cc

+// Copyright (c) 2011 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/renderer/java_bridge_dispatcher.h"
+
+#include "content/common/child_process.h"
+#include "content/common/java_bridge_messages.h"
+#include "content/common/npobject_util.h"  // For CreateNPVariant()
+#include "content/public/renderer/render_thread.h"
+#include "content/public/renderer/render_view.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebBindings.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
+
+JavaBridgeDispatcher::JavaBridgeDispatcher(
+    content::RenderView* render_view,
+    const IPC::ChannelHandle& channel_handle)
+    : RenderViewObserver(render_view) {
+  channel_.reset(JavaBridgeChannel::GetJavaBridgeChannel(
+      channel_handle, ChildProcess::current()->io_message_loop_proxy()));
+}
+
+JavaBridgeDispatcher::~JavaBridgeDispatcher() {
+  for (ObjectMap::const_iterator iter = objects_.begin();
+      iter != objects_.end(); ++iter) {
+    WebKit::WebBindings::releaseObject(NPVARIANT_TO_OBJECT(iter->second));
+  }
+}
+
+bool JavaBridgeDispatcher::OnMessageReceived(const IPC::Message& msg) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(JavaBridgeDispatcher, msg)
+    IPC_MESSAGE_HANDLER(JavaBridgeMsg_AddNamedObject, OnAddNamedObject)
+    IPC_MESSAGE_HANDLER(JavaBridgeMsg_RemoveNamedObject,
+                        OnRemoveNamedObject)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
+void JavaBridgeDispatcher::DidClearWindowObject(WebKit::WebFrame* web_frame) {
+  DCHECK_EQ(content::RenderThread::Get()->GetMessageLoop(),

[jam, 2011/10/19 23:46:19]

(and below)

you don't need to test that RVO interface is called on the right thread. if you
really wanted to test that, then individual observers wouldn't be the best spot

[Steve Block, 2011/10/20 09:43:08]

Done.

+      MessageLoop::current());
+  // We only inject objects into the main frame.
+  if (web_frame != render_view()->GetWebView()->mainFrame())
+    return;
+
+  // Note that we have to (re)bind all objects, as they will have been unbound
+  // when the window object was cleared.
+  for (ObjectMap::const_iterator iter = objects_.begin();
+      iter != objects_.end(); ++iter) {
+    // This refs the NPObject. This reference is dropped when either the window
+    // object is later cleared, or the object is GC'ed. So the object may be
+    // deleted at any time after OnRemoveNamedObject() is called.
+    web_frame->bindToWindowObject(iter->first,
+        NPVARIANT_TO_OBJECT(iter->second));
+  }
+}
+
+void JavaBridgeDispatcher::OnAddNamedObject(
+    const string16& name,
+    const NPVariant_Param& variant_param) {
+  DCHECK_EQ(content::RenderThread::Get()->GetMessageLoop(),
+      MessageLoop::current());
+  DCHECK_EQ(variant_param.type, NPVARIANT_PARAM_SENDER_OBJECT_ROUTING_ID);
+  // This creates an NPObject, wrapped as an NPVariant. We don't need the
+  // containing window or the page URL, as we don't do re-entrant sync IPC.
+  NPVariant variant;
+  bool created =
+      CreateNPVariant(variant_param, channel_.get(), &variant, NULL, GURL());
+  DCHECK(created);
+  DCHECK_EQ(variant.type, NPVariantType_Object);
+
+  // The NPObject is created with a ref count of one, which we remove when
+  // OnRemoveNamedObject() is called for that object.
+  ObjectMap::iterator iter = objects_.find(name);
+  if (iter != objects_.end()) {
+    WebKit::WebBindings::releaseObject(NPVARIANT_TO_OBJECT(iter->second));
+  }
+  objects_[name] = variant;
+}
+
+void JavaBridgeDispatcher::OnRemoveNamedObject(const string16& name) {
+  DCHECK_EQ(content::RenderThread::Get()->GetMessageLoop(),

[jam, 2011/10/19 23:46:19]

ditto: this isn't needed

[Steve Block, 2011/10/20 09:43:08]

Done.

+      MessageLoop::current());
+  // Removing an object does not unbind it from JavaScript until the window
+  // object is next cleared. Note that the browser checks that the named object
+  // is present.
+  ObjectMap::iterator iter = objects_.find(name);
+  DCHECK(iter != objects_.end());
+  WebKit::WebBindings::releaseObject(NPVARIANT_TO_OBJECT(iter->second));
+  objects_.erase(iter);
+}