Removed possible ArrayIndexOutOfBoundsException.

Fixed code formatting and comments.

gcloud-java-examples/src/main/java/com/google/gcloud/examples/dns/DnsExample.java

@@ -35,11 +35,11 @@
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
-/**
+/*
  * An example of using Google Cloud DNS.
  *
- * <p>This example creates, deletes, gets, and lists zones, and creates and deletes DNS records of
- * type A.
+ * <p>This example creates, deletes, gets, and lists zones. It also creates and deletes DNS records
+ * of type A, and lists DNS records.
  *
  * <p>Steps needed for running the example:
  * <ol>
@@ -57,10 +57,10 @@
  * quota}</li>
  * </ol>
  *
- * <p>The first parameter is an optional {@code project_id} (logged-in project will be used if not
- * supplied). The second parameter is a DNS operation (list, delete, create,...). The remaining
- * arguments are specific to the operation. See each action's run method for the specific
- * interaction.
+ * <p>The first parameter is an optional {@code project_id} (project specified in the Google Cloud
+ * SDK configuration (see {@code gcloud config list}) will be used if not supplied). The second
+ * parameter is a DNS operation (list, delete, create, ...). The remaining arguments are specific to
+ * the operation. See each action's {@code run} method for the specific arguments.
  */
 public class DnsExample {
 
@@ -78,7 +78,7 @@ private interface DnsAction {
   private static class CreateZoneAction implements DnsAction {
 
     /**
-     * Creates a zone with the provided name, dns name and description (in this order).
+     * Creates a zone with the provided name, DNS name and description (in this order).
      */
     @Override
     public void run(Dns dns, String... args) {
@@ -113,8 +113,7 @@ public void run(Dns dns, String... args) {
       if (zoneIterator.hasNext()) {
         System.out.println("The project contains the following zones:");
         while (zoneIterator.hasNext()) {
-          Zone zone = zoneIterator.next();
-          printZone(zone);
+          printZone(zoneIterator.next());
         }
       } else {
         System.out.println("Project contains no zones.");
@@ -211,18 +210,10 @@ public void run(Dns dns, String... args) {
           .delete(record)
           .build();
       changeRequest = dns.applyChangeRequest(zoneName, changeRequest);
-      System.out.printf("The request for deleting A record %s for zone %s was successfully " +
-          "submitted and assigned ID %s.%n", recordName, zoneName, changeRequest.id());
+      System.out.printf("The request for deleting A record %s for zone %s was successfully "
+          + "submitted and assigned ID %s.%n", recordName, zoneName, changeRequest.id());
       System.out.print("Waiting for deletion to happen...");
-      while (changeRequest.status().equals(ChangeRequest.Status.PENDING)) {
-        System.out.print(".");
-        try {
-          Thread.sleep(500);
-        } catch (InterruptedException e) {
-          System.err.println("Thread was interrupted while waiting.");
-        }
-        changeRequest = dns.getChangeRequest(zoneName, changeRequest.id());
-      }
+      waitForChangeToFinish(dns, zoneName, changeRequest);
       System.out.printf("%nThe deletion has been completed.%n");
     }
 
@@ -262,22 +253,12 @@ public void run(Dns dns, String... args) {
           .records(ImmutableList.of(ip))
           .ttl(ttl, TimeUnit.SECONDS)
           .build();
-      ChangeRequest changeRequest = ChangeRequest.builder()
-          .add(record)
-          .build();
+      ChangeRequest changeRequest = ChangeRequest.builder().add(record).build();
       changeRequest = dns.applyChangeRequest(zoneName, changeRequest);
-      System.out.printf("The request for adding A record %s for zone %s was successfully " +
-          "submitted and assigned ID %s.%n", recordName, zoneName, changeRequest.id());
+      System.out.printf("The request for adding A record %s for zone %s was successfully "
+          + "submitted and assigned ID %s.%n", recordName, zoneName, changeRequest.id());
       System.out.print("Waiting for addition to happen...");
-      while (changeRequest.status().equals(ChangeRequest.Status.PENDING)) {
-        System.out.print(".");
-        try {
-          Thread.sleep(500);
-        } catch (InterruptedException e) {
-          System.err.println("Thread was interrupted while waiting.");
-        }
-        changeRequest = dns.getChangeRequest(zoneName, changeRequest.id());
-      }
+      waitForChangeToFinish(dns, zoneName, changeRequest);
       System.out.printf("The addition has been completed.%n");
     }
 
@@ -333,8 +314,8 @@ public boolean check(String... args) {
   private static class ListChangesAction implements DnsAction {
 
     /**
-     * Lists all the changes for a given zone. Optionally, an order, "descending" or "ascending" can
-     * be specified using the last parameter.
+     * Lists all the changes for a given zone. Optionally, an order ("descending" or "ascending")
+     * can be specified using the last parameter.
      */
     @Override
     public void run(Dns dns, String... args) {
@@ -398,7 +379,7 @@ public void run(Dns dns, String... args) {
 
     @Override
     public boolean check(String... args) {
-      if (args.length == 0) {
+      if (args.length == 0 || args.length == 1) {
         return true;
       }
       if ("records".equals(args[1])) {
@@ -462,6 +443,21 @@ private static void printZone(Zone zone) {
     System.out.printf("Name servers: %s%n", Joiner.on(", ").join(zone.nameServers()));
   }
 
+  private static ChangeRequest waitForChangeToFinish(Dns dns, String zoneName,
+      ChangeRequest request) {
+    ChangeRequest current = request;
+    while (current.status().equals(ChangeRequest.Status.PENDING)) {
+      System.out.print(".");
+      try {
+        Thread.sleep(500);
+      } catch (InterruptedException e) {
+        System.err.println("Thread was interrupted while waiting.");
+      }
+      current = dns.getChangeRequest(zoneName, current.id());
+    }
+    return current;
+  }
+
   private static void printUsage() {
     StringBuilder actionAndParams = new StringBuilder();
     for (Map.Entry<String, DnsAction> entry : ACTIONS.entrySet()) {
@@ -508,12 +504,13 @@ public static void main(String... args) throws Exception {
       return;
     } catch (Exception ex) {
       System.out.println("Failed to parse request.");
+      System.out.println("Expected: " + action.params());
       ex.printStackTrace();
       return;
     }
     if (valid) {
       DnsOptions.Builder optionsBuilder = DnsOptions.builder();
-      if(projectId != null) {
+      if (projectId != null) {
         optionsBuilder.projectId(projectId);
       }
       Dns dns = optionsBuilder.build().service();

gcloud-java-examples/src/main/java/com/google/gcloud/examples/dns/snippets/CreateAndListDnsRecords.java

@@ -37,7 +37,6 @@
 public class CreateAndListDnsRecords {
 
   public static void main(String... args) {
-
     // Create a service object.
     // The project ID and credentials will be inferred from the environment.
     Dns dns = DnsOptions.defaultInstance().service();
@@ -63,7 +62,7 @@ public static void main(String... args) {
     Iterator<DnsRecord> recordIterator = zone.listDnsRecords().iterateAll();
     while (recordIterator.hasNext()) {
       DnsRecord current = recordIterator.next();
-      if(toCreate.name().equals(current.name()) && toCreate.type().equals(current.type())) {
+      if (toCreate.name().equals(current.name()) && toCreate.type().equals(current.type())) {
         changeBuilder.delete(current);
       }
     }

gcloud-java-examples/src/main/java/com/google/gcloud/examples/dns/snippets/CreateAndListZones.java

@@ -51,11 +51,11 @@ public static void main(String... args) {
     Zone createdZone = dns.create(zoneInfo);
     System.out.printf("Zone was created and assigned ID %s.%n", createdZone.id());
 
-    // Now list all the zones within this project and print them using the default toString
+    // Now list all the zones within this project
     Iterator<Zone> zoneIterator = dns.listZones().iterateAll();
     int counter = 1;
     while (zoneIterator.hasNext()) {
-      System.out.printf("#%d.: %s", counter, zoneIterator.next().toString());
+      System.out.printf("#%d.: %s%n%n", counter, zoneIterator.next().toString());
       counter++;
     }
   }

gcloud-java-examples/src/main/java/com/google/gcloud/examples/dns/snippets/DeleteZone.java

@@ -36,10 +36,9 @@
 public class DeleteZone {
 
   public static void main(String... args) {
-
     // Create a service object.
     // The project ID and credentials will be inferred from the environment.
-    Dns dns = DnsOptions.builder().build().service();
+    Dns dns = DnsOptions.defaultInstance().service();
 
     // Change this to a zone name that exists within your project and that you want to delete.
     String zoneName = "some-sample-zone";
@@ -63,14 +62,15 @@ public static void main(String... args) {
       changeRequest = dns.applyChangeRequest(zoneName, changeRequest);
 
       // Wait for change to finish, but save data traffic by transferring only ID and status
-      Dns.ChangeRequestOption option = Dns.ChangeRequestOption.fields(Dns.ChangeRequestField.STATUS);
+      Dns.ChangeRequestOption option =
+          Dns.ChangeRequestOption.fields(Dns.ChangeRequestField.STATUS);
       while (ChangeRequest.Status.PENDING.equals(changeRequest.status())) {
         System.out.println("Waiting for change to complete. Going to sleep for 500ms...");
         try {
           Thread.sleep(500);
         } catch (InterruptedException e) {
-          System.err.println("The thread was interrupted while waiting for change request to be " +
-              "processed.");
+          System.err.println("The thread was interrupted while waiting for change request to be "
+              + "processed.");
         }
         // Update the change, but fetch only change ID and status
         changeRequest = dns.getChangeRequest(zoneName, changeRequest.id(), option);