Make it possible for SkyShell embedders to register services

We now register the sensor service from SkyDemo, which shows that embedders of
SkyShell can register their own Java services.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/969753003

apk/demo/AndroidManifest.xml

@@ -10,7 +10,7 @@
     <uses-permission android:name="android.permission.INTERNET"/>
     <uses-feature android:name="android.hardware.sensor.accelerometer" android:required="true" />
 
-    <application android:name="org.domokit.sky.shell.SkyApplication" android:label="Sky">
+    <application android:name="SkyDemoApplication" android:label="Sky">
         <activity android:name="SkyDemoActivity"
                   android:launchMode="singleTask"
                   android:theme="@android:style/Theme.Holo.Light.NoActionBar"

apk/demo/BUILD.gn

@@ -9,9 +9,17 @@ import("//build/config/android/rules.gni")
 import("//sky/apk/rules.gni")
 
 android_library("java") {
-  java_files = [ "org/domokit/sky/demo/SkyDemoActivity.java" ]
+  java_files = [
+    "org/domokit/sky/demo/SkyDemoActivity.java",
+    "org/domokit/sky/demo/SkyDemoApplication.java",
+  ]
 
   deps = [
+    "//base:base_java",
+    "//mojo/public/java:bindings",
+    "//mojo/public/java:system",
+    "//sky/services/sensors",
+    "//sky/services/sensors:interfaces_java",
     "//sky/shell:java",
   ]
 }

apk/demo/org/domokit/sky/demo/SkyDemoApplication.java

+// Copyright 2015 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.domokit.sky.demo;
+
+import android.content.Context;
+
+import org.chromium.mojo.system.Core;
+import org.chromium.mojo.system.MessagePipeHandle;
+import org.chromium.mojom.sensors.SensorService;
+import org.domokit.sensors.SensorServiceImpl;
+import org.domokit.sky.shell.ServiceFactory;
+import org.domokit.sky.shell.ServiceRegistry;
+import org.domokit.sky.shell.SkyApplication;
+
+/**
+ * SkyDemo implementation of {@link android.app.Application}
+ */
+public class SkyDemoApplication extends SkyApplication {
+    @Override
+    public void onCreate() {
+        super.onCreate();
+
+        ServiceRegistry.SHARED.register(SensorService.MANAGER.getName(), new ServiceFactory() {
+            @Override
+            public void connectToService(Context context, Core core, MessagePipeHandle pipe) {
+                new SensorServiceImpl(context, core, pipe);
+            }
+        });
+    }
+}

shell/BUILD.gn

@@ -75,6 +75,8 @@ android_library("java") {
     "org/domokit/sky/shell/GestureProvider.java",
     "org/domokit/sky/shell/JavaServiceProvider.java",
     "org/domokit/sky/shell/PlatformView.java",
+    "org/domokit/sky/shell/ServiceFactory.java",
+    "org/domokit/sky/shell/ServiceRegistry.java",
     "org/domokit/sky/shell/SkyActivity.java",
     "org/domokit/sky/shell/SkyApplication.java",
     "org/domokit/sky/shell/SkyMain.java",
@@ -88,8 +90,6 @@ android_library("java") {
     "//mojo/public/java:system",
     "//mojo/services/network/public/interfaces:interfaces_java",
     "//sky/services/oknet",
-    "//sky/services/sensors",
-    "//sky/services/sensors:interfaces_java",
     "//sky/services/viewport:viewport_java",
   ]
 }

shell/org/domokit/sky/shell/JavaServiceProvider.java

@@ -12,14 +12,10 @@ import org.chromium.mojo.system.Core;
 import org.chromium.mojo.system.MessagePipeHandle;
 import org.chromium.mojo.system.MojoException;
 import org.chromium.mojo.system.impl.CoreImpl;
-import org.chromium.mojom.mojo.NetworkService;
 import org.chromium.mojom.mojo.ServiceProvider;
-import org.chromium.mojom.sensors.SensorService;
-import org.domokit.oknet.NetworkServiceImpl;
-import org.domokit.sensors.SensorServiceImpl;
 
 /**
- * A class to intialize the network.
+ * A collection of services implemented in Java.
  **/
 @JNINamespace("sky::shell")
 public class JavaServiceProvider implements ServiceProvider {
@@ -49,13 +45,11 @@ public class JavaServiceProvider implements ServiceProvider {
 
     @Override
     public void connectToService(String interfaceName, MessagePipeHandle pipe) {
-        if (interfaceName.equals(NetworkService.MANAGER.getName())) {
-            new NetworkServiceImpl(mContext, mCore, pipe);
-            return;
-        } else if (interfaceName.equals(SensorService.MANAGER.getName())) {
-            new SensorServiceImpl(mContext, mCore, pipe);
+        ServiceFactory factory = ServiceRegistry.SHARED.get(interfaceName);
+        if (factory == null) {
+            pipe.close();
             return;
         }
-        pipe.close();
+        factory.connectToService(mContext, mCore, pipe);
     }
 }

shell/org/domokit/sky/shell/ServiceFactory.java

+// Copyright 2015 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.domokit.sky.shell;
+
+import android.content.Context;
+
+import org.chromium.mojo.system.Core;
+import org.chromium.mojo.system.MessagePipeHandle;
+
+/**
+ * An interface for creating services. Instances of this interface can be
+ * registered with ServiceRegistry and thereby made available to non-Java
+ * clients.
+ **/
+public interface ServiceFactory {
+    public void connectToService(Context context, Core core, MessagePipeHandle pipe);
+}

shell/org/domokit/sky/shell/ServiceRegistry.java

+// Copyright 2015 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.domokit.sky.shell;
+
+import java.util.Map;
+import java.util.TreeMap;
+
+/**
+ * An registry for services.
+ **/
+public class ServiceRegistry {
+    private Map<String, ServiceFactory> mRegistrations;
+
+    public static final ServiceRegistry SHARED = new ServiceRegistry();
+
+    private ServiceRegistry() {
+        mRegistrations = new TreeMap<String, ServiceFactory>();
+    }
+
+    public void register(String interfaceName, ServiceFactory connector) {
+        assert !mRegistrations.containsKey(interfaceName);
+        assert connector != null;
+        mRegistrations.put(interfaceName, connector);
+    }
+
+    public ServiceFactory get(String interfaceName) {
+        return mRegistrations.get(interfaceName);
+    }
+}

shell/org/domokit/sky/shell/SkyApplication.java

@@ -4,6 +4,7 @@
 
 package org.domokit.sky.shell;
 
+import android.content.Context;
 import android.util.Log;
 
 import org.chromium.base.BaseChromiumApplication;
@@ -12,16 +13,20 @@ import org.chromium.base.ResourceExtractor;
 import org.chromium.base.library_loader.LibraryLoader;
 import org.chromium.base.library_loader.LibraryProcessType;
 import org.chromium.base.library_loader.ProcessInitException;
+import org.chromium.mojo.system.Core;
+import org.chromium.mojo.system.MessagePipeHandle;
+import org.chromium.mojom.mojo.NetworkService;
+import org.domokit.oknet.NetworkServiceImpl;
 
 /**
- * MojoShell implementation of {@link android.app.Application}, managing application-level global
+ * Sky implementation of {@link android.app.Application}, managing application-level global
  * state and initializations.
  */
 public class SkyApplication extends BaseChromiumApplication {
     private static final String TAG = "SkyApplication";
     private static final String PRIVATE_DATA_DIRECTORY_SUFFIX = "sky_shell";
     private static final String[] SKY_MANDATORY_PAKS = {
-            "icudtl.dat",
+        "icudtl.dat",
     };
 
     @Override
@@ -29,19 +34,14 @@ public class SkyApplication extends BaseChromiumApplication {
         super.onCreate();
         initializeJavaUtils();
         initializeNative();
+        initializeServiceRegistry();
         ResourceExtractor.setMandatoryPaksToExtract(SKY_MANDATORY_PAKS);
     }
 
-    /**
-     * Initializes Java-side utils.
-     */
     private void initializeJavaUtils() {
         PathUtils.setPrivateDataDirectorySuffix(PRIVATE_DATA_DIRECTORY_SUFFIX);
     }
 
-    /**
-     * Loads the native library.
-     */
     private void initializeNative() {
         try {
             LibraryLoader.get(LibraryProcessType.PROCESS_BROWSER).ensureInitialized();
@@ -50,4 +50,12 @@ public class SkyApplication extends BaseChromiumApplication {
             throw new RuntimeException(e);
         }
     }
+
+    private void initializeServiceRegistry() {
+        ServiceRegistry.SHARED.register(NetworkService.MANAGER.getName(), new ServiceFactory() {
+            public void connectToService(Context context, Core core, MessagePipeHandle pipe) {
+                new NetworkServiceImpl(context, core, pipe);
+            }
+        });
+    }
 }