Java versions of BlimpContents[,Observer] and BlimpNavigationController

blimp/client/core/android/java/src/org/chromium/blimp/core/BlimpContentsImpl.java

Index: blimp/client/core/android/java/src/org/chromium/blimp/core/BlimpContentsImpl.java
diff --git a/blimp/client/core/android/java/src/org/chromium/blimp/core/BlimpContentsImpl.java b/blimp/client/core/android/java/src/org/chromium/blimp/core/BlimpContentsImpl.java
new file mode 100644
index 0000000000000000000000000000000000000000..673270813bbeb2813600be573814b6b8a0120b60
--- /dev/null
+++ b/blimp/client/core/android/java/src/org/chromium/blimp/core/BlimpContentsImpl.java
@@ -0,0 +1,83 @@
+// Copyright 2016 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.
+
+package org.chromium.blimp.core;
+
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.base.annotations.JNINamespace;
+import org.chromium.blimp.core_public.BlimpContents;
+import org.chromium.blimp.core_public.BlimpContentsObserver;
+import org.chromium.blimp.core_public.BlimpNavigationController;
+
+/**
+ * BlimpContentsImpl is a Java wrapper to allow communicating with the native BlimpContentsImpl
+ * object.
+ */
+@JNINamespace("blimp::client")
+public class BlimpContentsImpl implements BlimpContents {
+    @CalledByNative
+    private static BlimpContentsImpl create(
+            long nativeBlimpContentsImplAndroid, BlimpNavigationController navigationController) {
+        return new BlimpContentsImpl(nativeBlimpContentsImplAndroid, navigationController);
+    }
+
+    private long mNativeBlimpContentsImplAndroid;
+
+    // Given the importance of the navigation controller, this member is kept directly in Java to
+    // ensure that calls to getNavigationController() can be completed with no JNI-hop.
+    private BlimpNavigationController mBlimpNavigationController;
+
+    // The BlimpContentsObserverProxy is lazily created when the first observer is added. It is
+    // used instead of directly having an ObserverList in this class to ensure there is only a
+    // single JNI hop for each call to observers.
+    private BlimpContentsObserverProxy mObserverProxy;
+
+    private BlimpContentsImpl(
+            long nativeBlimpContentsImplAndroid, BlimpNavigationController navigationController) {
+        mNativeBlimpContentsImplAndroid = nativeBlimpContentsImplAndroid;
+        mBlimpNavigationController = navigationController;
+    }
+
+    @CalledByNative
+    private void clearNativePtr() {
+        mNativeBlimpContentsImplAndroid = 0;
+        mBlimpNavigationController = null;
+        if (mObserverProxy != null) {
+            mObserverProxy.destroy();
+            mObserverProxy = null;
+        }
+    }
+
+    @CalledByNative
+    private long getNativePtr() {
+        assert mNativeBlimpContentsImplAndroid != 0;
+        return mNativeBlimpContentsImplAndroid;
+    }
+
+    @Override
+    public BlimpNavigationController getNavigationController() {
+        return mBlimpNavigationController;
+    }
+
+    @Override
+    public void addObserver(BlimpContentsObserver observer) {
+        assert mNativeBlimpContentsImplAndroid != 0;
+        if (mObserverProxy == null) mObserverProxy = new BlimpContentsObserverProxy(this);
+        mObserverProxy.addObserver(observer);
+    }
+
+    @Override
+    public void removeObserver(BlimpContentsObserver observer) {
+        if (mObserverProxy == null) return;
+        mObserverProxy.removeObserver(observer);
+    }
+
+    @Override
+    public void destroy() {
+        assert mNativeBlimpContentsImplAndroid != 0;
+        nativeDestroy(mNativeBlimpContentsImplAndroid);
+    }
+
+    private native void nativeDestroy(long nativeBlimpContentsImplAndroid);
+}