---

shinfan · web-flow · commit 90988e86a148 · 2017-03-13T11:56:14.000-07:00
yaml --- r: 5465 b: refs/heads/master c: 7a310c4 h: refs/heads/master i: 5463: c16080d
diff --git a/[refs] b/[refs]
@@ -1,5 +1,5 @@
 ---
-refs/heads/master: 3919d63a5ff030a522ad07d5a46c3251998795e6
+refs/heads/master: 7a310c47d19dcfe71966276fe18a20914f332192
 refs/heads/travis: dae77e558b884bc1b165155482d76c8e40b0fca4
 refs/heads/gh-pages: 4936f6d1c43be1ab76229d2743bae07f4b4124b3
 refs/tags/0.0.9: 22f1839238f66c39e67ed4dfdcd273b1ae2e8444
diff --git a/trunk/APPENGINE.md b/trunk/APPENGINE.md
@@ -0,0 +1,33 @@
+Use Google Cloud Java Client with Google App Engine
+=================================================
+
+Quickstart
+----------
+This file provides extra instructions to set up Google Cloud Java Client with Google App Engine.
+
+See [Google Cloud JavaQuickstart](./README.md#quickstart) for general instructions on using Google Cloud Java.
+
+See [Quickstart for App Engine Standard Environment for Java](https://cloud.google.com/appengine/docs/standard/java/quickstart) for extra Google App Engine instructions.
+
+If you are using Maven, add this to your pom.xml file
+```xml
+<dependency>
+    <groupId>com.google.appengine</groupId>
+    <artifactId>appengine-api-1.0-sdk</artifactId>
+    <version>1.9.50</version>
+</dependency>
+```
+
+If you are using Gradle, add this to your dependencies
+```Groovy
+compile 'com.google.appengine:appengine-api-1.0-sdk:1.9.50'
+```
+If you are using SBT, add this to your dependencies
+```Scala
+libraryDependencies += "com.google.appengine" % "appengine-api-1.0-sdk" % "1.9.50"
+```
+
+To test with local dev server, run
+```
+mvn appengine:devserver
+```
diff --git a/trunk/README.md b/trunk/README.md
@@ -57,6 +57,8 @@ If you are using SBT, add this to your dependencies
 libraryDependencies += "com.google.cloud" % "google-cloud" % "0.9.4-alpha"
 ```
 
+For running on Google App Engine, see [more instructions here](./APPENGINE.md).
+
 Example Applications
 --------------------
 
diff --git a/trunk/google-cloud-core/src/main/java/com/google/cloud/ServiceOptions.java b/trunk/google-cloud-core/src/main/java/com/google/cloud/ServiceOptions.java
@@ -394,8 +394,17 @@ protected static String getAppEngineProjectId() {
       String serviceAccountName = (String) method.invoke(appIdentityService);
       int indexOfAtSign = serviceAccountName.indexOf('@');
       return serviceAccountName.substring(0, indexOfAtSign);
+    } catch (ClassNotFoundException exception) {
+      if (System.getProperty("com.google.appengine.runtime.version") != null) {
+        // Could not resolve appengine classes under GAE environment.
+        throw new RuntimeException("Google App Engine runtime detected "
+            + "(the environment variable \"com.google.appengine.runtime.version\" is set), "
+            + "but unable to resolve appengine-sdk classes. "
+            + "For more details see "
+            + "https://github.com/GoogleCloudPlatform/google-cloud-java/blob/master/APPENGINE.md");
+      }
+      return null;
     } catch (Exception ignore) {
-      // return null if can't determine
       return null;
     }
   }
