better messaging in sample apps when system properties are not defined

Author: aoberoi

sample/Archiving/README.md

@@ -19,7 +19,8 @@ Next, start the server using Gradle (which handles dependencies and setting up t
 $ gradle :sample/Archiving:run
 ```
 
-Or if you are using the Gradle Wrapper that is distributed with the project:
+Or if you are using the Gradle Wrapper that is distributed with the project, from the root project
+directory:
 
 ```
 $ ./gradlew :sample/Archiving:run

sample/Archiving/src/main/java/com/example/ArchivingServer.java

@@ -18,7 +18,7 @@ public class ArchivingServer {
 
     private static final String apiKey = System.getProperty("API_KEY");
     private static final String apiSecret = System.getProperty("API_SECRET");
-    private static final OpenTok opentok = new OpenTok(Integer.parseInt(apiKey), apiSecret);
+    private static OpenTok opentok;
     private static String sessionId;
 
     public static void main(String[] args) throws OpenTokException {
@@ -28,6 +28,8 @@ public static void main(String[] args) throws OpenTokException {
             System.exit(-1);
         }
 
+        opentok = new OpenTok(Integer.parseInt(apiKey), apiSecret);
+
         sessionId = opentok.createSession().getSessionId();
 
         externalStaticFileLocation("./public");

sample/HelloWorld/README.md

@@ -20,7 +20,8 @@ Next, start the server using Gradle (which handles dependencies and setting up t
 $ gradle :sample/HelloWorld:run
 ```
 
-Or if you are using the Gradle Wrapper that is distributed with the project:
+Or if you are using the Gradle Wrapper that is distributed with the project, from the root project
+directory:
 
 ```
 $ ./gradlew :sample/HelloWorld:run
@@ -93,10 +94,11 @@ a static class variable.
 public class HelloWorldServer {
 
   // ...
-  private static final OpenTok opentok = new OpenTok(Integer.parseInt(apiKey), apiSecret);
+  private static OpenTok opentok;
 
   public static void main(String[] args) throws OpenTokException {
     // ...
+    opentok = new OpenTok(Integer.parseInt(apiKey), apiSecret);
   }
 }
 ```

sample/HelloWorld/src/main/java/com/example/HelloWorldServer.java

@@ -13,7 +13,7 @@ public class HelloWorldServer {
 
     private static final String apiKey = System.getProperty("API_KEY");
     private static final String apiSecret = System.getProperty("API_SECRET");
-    private static final OpenTok opentok = new OpenTok(Integer.parseInt(apiKey), apiSecret);
+    private static OpenTok opentok;
     private static String sessionId;
 
     public static void main(String[] args) throws OpenTokException {
@@ -23,6 +23,8 @@ public static void main(String[] args) throws OpenTokException {
             System.exit(-1);
         }
 
+        opentok = new OpenTok(Integer.parseInt(apiKey), apiSecret);
+
         sessionId = opentok.createSession().getSessionId();
 
         externalStaticFileLocation("./public");