Add JavaBoundObject

content/browser/renderer_host/java/java_bound_object.h

+// 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.
+
+#ifndef CONTENT_BROWSER_RENDERER_HOST_JAVA_JAVA_BOUND_OBJECT_H_
+#define CONTENT_BROWSER_RENDERER_HOST_JAVA_JAVA_BOUND_OBJECT_H_
+
+#include <jni.h>
+#include <map>
+#include <string>
+
+#include "base/android/scoped_java_ref.h"
+#include "base/memory/linked_ptr.h"
+#include "content/browser/renderer_host/java/java_method.h"
+#include "third_party/npapi/bindings/npruntime.h"
+
+// Wrapper around a Java object.
+//
+// Represents a Java object for use in the Java bridge. Holds a global ref to
+// the Java object and provides the ability to invoke methods on it.
+// Interrogation of the Java object for its methods is done lazily. This class
+// is not generally threadsafe. However, it does allow for instances to be
+// created and destroyed on different threads.
+class JavaBoundObject {
+ public:
+  // Takes a Java object and creates a JavaBoundObject around it. Returns an
+  // NPObject with a ref count of one which owns the JavaBoundObject.
+  static NPObject* Create(const base::android::JavaRef<jobject>& object);
+
+  virtual ~JavaBoundObject();
+
+  // Gets the underlying JavaObject from a JavaBoundObject wrapped as an
+  // NPObject.
+  static jobject GetJavaObject(NPObject* object);
+
+  // Methods to implement the NPObject callbacks.
+  bool HasMethod(const std::string& name) const;
+  bool Invoke(const std::string& name, const NPVariant* args, size_t arg_count,
+              NPVariant* result);
+
+ private:
+  explicit JavaBoundObject(const base::android::JavaRef<jobject>& object);
+
+  void EnsureMethodsAreSetUp();
+
+  // Global ref to the underlying Java object. We use a naked jobject, rather
+  // than a ScopedJavaGlobalRef, as the global ref will be added and dropped on
+  // different threads.
+  jobject java_object_;
+
+  // Map of public methods, from method name to Method instance. Multiple
+  // entries will be present for overloaded methods. Note that we can't use
+  // scoped_ptr in STL containers as we can't copy it.
+  typedef std::multimap<std::string, linked_ptr<JavaMethod> > JavaMethodMap;
+  JavaMethodMap methods_;
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(JavaBoundObject);
+};
+
+#endif  // CONTENT_BROWSER_RENDERER_HOST_JAVA_JAVA_BOUND_OBJECT_H_