Doc update: GCM doc cleanup.

Change-Id: Ie84a6ebdd12a05c8dbe1fff97539aea90c93554c

Author: labtopia

docs/html/guide/google/gcm/c2dm.jd

@@ -17,7 +17,11 @@ page.title=Migration
 
 <ol>
 <li><a href="#history">Historical Overview</a></li>
-<li><a href="#diffs">How is GCM Different from C2DM?</a></li>
+<li><a href="#diffs">How is GCM Different from C2DM?</a>
+  <ol>
+    <li><a href="#interop">Relationship between C2DM and GCM</a></li>
+  </ol>
+</li>
 <li><a href="#migrating">Migrating Your Apps</a>
   <ol>
     <li><a href="#client">Client changes</a></li>
@@ -72,6 +76,14 @@ page.title=Migration
 <dd>There may be situations where the server ends up with 2 registration IDs for the same device. If the GCM response contains a registration ID, simply replace the registration ID you have with the one provided. With this feature your application doesn't need to send the device ID to your server anymore. For more information, see <a href="adv.html#canonical">Advanced Topics</a>.</dd>
 </dl>
 <p>GCM also provides helper libraries (<a href="{@docRoot}guide/google/gcm/client-javadoc/index.html">client</a> and <a href="{@docRoot}guide/google/gcm/server-javadoc/index.html">server</a>) to make writing your code easier.</p>
+
+<h3 id="interop">Relationship between C2DM and GCM</h3>
+
+<p>C2DM and GCM are not interoperable. For example, you cannot post notifications from GCM to C2DM registration IDs, nor can you use C2DM registration IDs as GCM registration IDs. From your server-side application, you must keep keep track of whether a registration ID is from C2DM or GCM and use the proper endpoint. </p>
+
+<p>As you transition from C2DM to GCM, your server needs to be aware of whether a given registration ID
+contains an old C2DM sender or a new GCM project ID. This is the approach we recommend: have the new app version (the one that uses GCM) send a bit along with the registration ID. This bit tells your server that this registration ID is for GCM. If you don't get the extra bit, you mark the registration ID as C2DM. Once no more valid registration IDs are marked as C2DM, you can complete the migration.</p>
+
 <h2 id="migrating">Migrating Your Apps</h2>
 <p>This section describes how to move existing C2DM apps to GCM.</p>
 <h3 id="client">Client changes</h3>

docs/html/guide/google/gcm/demo.jd

@@ -74,11 +74,11 @@ page.title=GCM Demo Application
   <li> From the SDK Manager, install <strong>Extras &gt; Google Cloud Messaging for Android Library</strong>.
 
 
-    <p>This creates a <code>gcm</code> directory under <code><em>YOUR_SDK_ROOT</em>/extras/google/</code> containing these subdirectories: <code>gcm-client</code>, <code>gcm-demo-appengine</code>, <code>gcm-demo-client</code>, <code>gcm-demo-server</code>, and <code>gcm-server</code>.</p>
+    <p>This creates a <code>gcm</code> directory under <code><em>YOUR_SDK_ROOT</em>/extras/google/</code> containing these subdirectories: <code>gcm-client</code>, <code>gcm-server</code>, <code>samples/gcm-demo-client</code>, <code>samples/gcm-demo-server</code>, and <code>samples/gcm-demo-appengine</code>.</p>
   </li>
 
-  <li>In a text editor, edit the <code>gcm-demo-server/WebContent/WEB-INF/classes/api.key</code> and replace the existing text with the API key obtained above.</li>
-  <li>In a shell window, go to the <code>gcm-demo-server</code> directory.</li>
+  <li>In a text editor, edit the <code>samples/gcm-demo-server/WebContent/WEB-INF/classes/api.key</code> and replace the existing text with the API key obtained above.</li>
+  <li>In a shell window, go to the <code>samples/gcm-demo-server</code> directory.</li>
   <li>Generate the server's WAR file by running <code>ant war</code>:</li>
 
   <pre class="prettyprint">$ ant war
@@ -112,13 +112,13 @@ Total time: 0 seconds
 <p>To set up the server using a standard App Engine for Java:</p>
 <ol>
   <li> From the SDK Manager, install <strong>Extras &gt; Google Cloud Messaging for Android Library</strong>.
-    <p>This creates a <code>gcm</code> directory under <code><em>YOUR_SDK_ROOT</em>/extras/google/</code> containing these subdirectories: <code>gcm-client</code>, <code>gcm-demo-appengine</code>, <code>gcm-demo-client</code>, <code>gcm-demo-server</code>, and <code>gcm-server</code>.</p>
+    <p>This creates a <code>gcm</code> directory under <code><em>YOUR_SDK_ROOT</em>/extras/google/</code> containing these subdirectories: <code>gcm-client</code>, <code>gcm-server</code>, <code>samples/gcm-demo-client</code>, <code>samples/gcm-demo-server</code>, and <code>samples/gcm-demo-appengine</code>.</p>
   </li>
-  <li>In a text editor, edit the <code>gcm-demo-appengine/src/com/google/android/gcm/demo/server/ApiKeyInitializer.java</code> and replace the existing text with the API key obtained above.
+  <li>In a text editor, edit <code>samples/gcm-demo-appengine/src/com/google/android/gcm/demo/server/ApiKeyInitializer.java</code> and replace the existing text with the API key obtained above.
   <p class="note"><strong>Note:</strong> The API key value set in that class will be used just once to create a persistent entity on App Engine. If you deploy the application, you can use App Engine's <code>Datastore Viewer</code> to change it later.</p>
 
   </li>
-  <li>In a shell window, go to the <code>gcm-api-server</code> directory.</li>
+  <li>In a shell window, go to the <code>samples/gcm-demo-appengine</code> directory.</li>
   <li>Start the development App Engine server by <code>ant runserver</code>, using the <code>-Dsdk.dir</code> to indicate the location of the App Engine SDK and <code>-Dserver.host</code> to set your server's hostname or IP address:</li>
 
 <pre class="prettyprint">
@@ -163,9 +163,9 @@ runserver:
 <p>To set up the device:</p>
 <ol>
   <li> From the SDK Manager, install <strong>Extras &gt; Google Cloud Messaging for Android Library</strong>.
-    <p>This creates a <code>gcm</code> directory under <code><em>YOUR_SDK_ROOT</em>/extras/google</code> containing these subdirectories: <code>gcm-client</code>, <code>gcm-demo-appengine</code>, <code>gcm-demo-client</code>, <code>gcm-demo-server</code>, <code>gcm-server</code>, and <code>source.properties</code>.</p>
+    <p>This creates a <code>gcm</code> directory under <code><em>YOUR_SDK_ROOT</em>/extras/google</code> containing these subdirectories: <code>gcm-client</code>, <code>gcm-server</code>, <code>samples/gcm-demo-client</code>, <code>samples/gcm-demo-server</code>, and <code>samples/gcm-demo-appengine</code>.</p>
   </li>
-  <li>Using a text editor, open  <code>gcm-demo-client/src/com/google/android/gcm/demo/app/CommonUtilities.java</code> and set the proper values for the <code>SENDER_ID</code> and <code>SERVER_URL</code> constants. For example:</li>
+  <li>Using a text editor, open  <code>samples/gcm-demo-client/src/com/google/android/gcm/demo/app/CommonUtilities.java</code> and set the proper values for the <code>SENDER_ID</code> and <code>SERVER_URL</code> constants. For example:</li>
 
 <pre class="prettyprint pretty-java">
 static final String SERVER_URL = &quot;http://192.168.1.10:8080/gcm-demo&quot;;

docs/html/guide/google/gcm/gs.jd

@@ -85,7 +85,7 @@ page.title=GCM: Getting Started
 <p class="note"><strong>Note:</strong> If you need to rotate the key, click  <strong>Generate new key</strong>. A new key  will be created while the old one will still be active for up to 24 hours. If you want to get rid of the old key immediately (for example, if you feel it was compromised), click <strong>Delete key</strong>.</p>
 
 <h2 id="libs">Install the Helper Libraries</h2>
-<p>To perform the steps described in the following sections, you must first install the helper libraries (reference: <a href="{@docRoot}guide/google/gcm/client-javadoc/index.html">client</a> and <a href="{@docRoot}guide/google/gcm/server-javadoc/index.html">server</a>). From the SDK Manager, install <strong>Extras &gt; Google Cloud Messaging for Android Library</strong>. This creates a <code>gcm</code> directory under <code><em>YOUR_SDK_ROOT</em>/extras/google/</code> containing these subdirectories: <code>gcm-client</code>, <code>gcm-demo-appengine</code>, <code>gcm-demo-client</code>, <code>gcm-demo-server</code>, and <code>gcm-server</code>.</p>
+<p>To perform the steps described in the following sections, you must first install the helper libraries (reference: <a href="{@docRoot}guide/google/gcm/client-javadoc/index.html">client</a> and <a href="{@docRoot}guide/google/gcm/server-javadoc/index.html">server</a>). From the SDK Manager, install <strong>Extras &gt; Google Cloud Messaging for Android Library</strong>. This creates a <code>gcm</code> directory under <code><em>YOUR_SDK_ROOT</em>/extras/google/</code> containing these subdirectories: <code>gcm-client</code>, <code>gcm-server</code>, <code>samples/gcm-demo-client</code>, <code>samples/gcm-demo-server</code>, and <code>samples/gcm-demo-appengine</code>.</p>
 <h2 id="android-app">Writing the Android Application</h2>
 <p>This section describes the steps involved in writing an Android application that uses GCM.</p>
 <h4>Step 1: Copy the gcm.jar file into your application classpath</h4>
@@ -104,9 +104,16 @@ page.title=GCM: Getting Started
 <p> This permission must be called <code>my_app_package.permission.C2D_MESSAGE</code> (where <code>my_app_package</code> is the package name of your app as defined by the manifest tag), otherwise it will not  work.</p>
 <p class="note"><strong>Note:</strong> This permission is not required if you are targeting your application to 4.1 or above (i.e., minSdkVersion 16)</p>
 
-  <li>Add the permission to receive GCM messages:</li>
+  <li>Add the following permissions:</li>
 
-<pre class="prettyprint pretty-xml">&lt;uses-permission android:name=&quot;com.google.android.c2dm.permission.RECEIVE&quot; /&gt;</pre>
+<pre class="prettyprint pretty-xml">&lt;!-- App receives GCM messages. --&gt;
+&lt;uses-permission android:name=&quot;com.google.android.c2dm.permission.RECEIVE&quot; /&gt;
+&lt;!-- GCM connects to Google Services. --&gt;
+&lt;uses-permission android:name=&quot;android.permission.INTERNET&quot; /&gt; 
+&lt;!-- GCM requires a Google account. --&gt;
+&lt;uses-permission android:name=&quot;android.permission.GET_ACCOUNTS&quot; /&gt;
+&lt;!-- Keeps the processor from sleeping when a message is received. --&gt;
+&lt;uses-permission android:name=&quot;android.permission.WAKE_LOCK&quot; /&gt;</pre>
 
   <li>Add the following broadcast receiver:</li>
 
@@ -127,7 +134,7 @@ page.title=GCM: Getting Started
  <pre class="prettyprint pretty-xml">&lt;service android:name=&quot;.GCMIntentService&quot; /&gt;</pre>
 
 </ol>
-<p> This intent service will be called by the <code>GCMBroadcastReceiver</code> (which is is provided by GCM library), as shown in the next step. It must be named <code>my_app_package.GCMIntentService</code>, unless you use a subclass of <code>GCMBroadcastReceiver</code> that overrides the method used to name the service.</p>
+<p>This intent service will be called by the <code>GCMBroadcastReceiver</code> (which is is provided by GCM library), as shown in the next step. It must be a subclass of <code>com.google.android.gcm.GCMBaseIntentService</code>, must contain a public constructor, and should be named <code>my_app_package.GCMIntentService</code> (unless you use a subclass of <code>GCMBroadcastReceiver</code> that overrides the method used to name the service).</p>
 <h4><br>
   Step 3: Write the my_app_package.GCMIntentService class</h4>
 <p>Next write the <code>my_app_package.GCMIntentService</code> class, overriding the following callback methods (which are called by <code>GCMBroadcastReceiver</code>):<br>

docs/html/guide/google/gcm/index.jd

@@ -5,7 +5,7 @@ page.title=Google Cloud Messaging for Android
 <p><img src="{@docRoot}images/gcm/gcm-logo.png" /></p>
 <p>Google Cloud Messaging for Android (GCM) is a service that helps developers send data from servers to their Android applications on Android devices. This could be a lightweight message telling the Android application that there is new data to be fetched from the server (for instance, a movie uploaded by a friend), or it could be a message containing up to 4kb of payload data (so apps like instant messaging can consume the message directly). The GCM service handles all aspects of queueing of messages and delivery to the target Android application running on the target device.</p>
 
-<p>To learn more about GCM, read the following documents:</p>
+<p>To learn more about GCM, you can join the <a href="https://groups.google.com/forum/?fromgroups#!forum/android-gcm">android-gcm group</a> and read the following documents:</p>
 
 <dl>
   <dt><strong><a href="{@docRoot}guide/google/gcm/gs.html">Getting Started</a></strong></dt>
@@ -23,3 +23,4 @@ page.title=Google Cloud Messaging for Android
 <p>GCM also provides helper libraries for <a href="{@docRoot}guide/google/gcm/client-javadoc/index.html"><strong>client</strong></a> and <a href="{@docRoot}guide/google/gcm/server-javadoc/index.html"><strong>server</strong></a> development.</p>
 
 
+