Converter Async.invoke to Async.function (#11)

Author: mfateev

src/main/java/com/uber/cadence/samples/hello/HelloAsync.java

@@ -21,6 +21,7 @@
 import com.uber.cadence.worker.Worker;
 import com.uber.cadence.workflow.Async;
 import com.uber.cadence.workflow.Functions;
+import com.uber.cadence.workflow.Functions.Func;
 import com.uber.cadence.workflow.Promise;
 import com.uber.cadence.workflow.Workflow;
 import com.uber.cadence.workflow.WorkflowMethod;
@@ -47,7 +48,7 @@ public interface GreetingActivities {
 
     /**
      * GreetingWorkflow implementation that calls GreetingsActivities#composeGreeting
-     * using {@link Async#invoke(Functions.Proc)}.
+     * using {@link Async#function(Func)}.
      */
     public static class GreetingWorkflowImpl implements GreetingWorkflow {
 
@@ -60,8 +61,8 @@ public static class GreetingWorkflowImpl implements GreetingWorkflow {
         @Override
         public String getGreeting(String name) {
              // Async.invoke takes method reference and activity parameters and returns Promise.
-             Promise<String> hello = Async.invoke(activities::composeGreeting, "Hello", name);
-             Promise<String> bye = Async.invoke(activities::composeGreeting, "Bye", name);
+             Promise<String> hello = Async.function(activities::composeGreeting, "Hello", name);
+             Promise<String> bye = Async.function(activities::composeGreeting, "Bye", name);
 
              // Promise is similar to the Java Future. Promise#get blocks until result is ready.
              return hello.get() + "\n" + bye.get();

src/main/java/com/uber/cadence/samples/hello/HelloAsyncLambda.java

@@ -72,11 +72,11 @@ public String getGreeting(String name) {
             // Async.invoke accepts not only activity or child workflow method references
             // but lambda functions as well. Behind the scene it allocates a thread
             // to execute it asynchronously.
-            Promise<String> result1 = Async.invoke(() -> {
+            Promise<String> result1 = Async.function(() -> {
                 String greeting = activities.getGreeting();
                 return activities.composeGreeting(greeting, name);
             });
-            Promise<String> result2 = Async.invoke(() -> {
+            Promise<String> result2 = Async.function(() -> {
                 String greeting = activities.getGreeting();
                 return activities.composeGreeting(greeting, name);
             });

src/main/java/com/uber/cadence/samples/hello/HelloChild.java

@@ -63,7 +63,7 @@ public String getGreeting(String name) {
             GreetingChild child = Workflow.newWorkflowStub(GreetingChild.class);
 
             // This is blocking call that returns only after child is completed.
-            Promise<String> greeting = Async.invoke(child::composeGreeting, "Hello", name);
+            Promise<String> greeting = Async.function(child::composeGreeting, "Hello", name);
             // Do something else here
             return greeting.get(); // blocks waiting for child to complete
         }