Fix some lints. (#123)

build.gradle.kts

@@ -93,6 +93,13 @@ subprojects {
     sourceCompatibility = "11"
 
     options.errorprone.disableWarningsInGeneratedCode.set(true)
+    options.errorprone.disable(
+        // We use toString() in proto messages for debugging reasons.
+        "LiteProtoToString",
+        // This check is proposing to use a guava API instead...
+        "StringSplitter",
+        // This is conflicting with a javadoc warn lint
+        "MissingSummary")
     options.errorprone.excludedPaths.set(".*/build/generated/.*")
   }
 

sdk-core-impl/src/main/java/dev/restate/sdk/core/impl/MessageHeader.java

@@ -29,8 +29,8 @@ public int getLength() {
 
   public long encode() {
     long res = 0L;
-    res |= ((long) (type.encode()) << 48);
-    res |= ((long) (flags) << 32);
+    res |= ((long) type.encode() << 48);
+    res |= ((long) flags << 32);
     res |= length;
     return res;
   }

sdk-core-impl/src/main/java/dev/restate/sdk/core/impl/ProtocolException.java

@@ -11,6 +11,7 @@ public class ProtocolException extends RuntimeException {
   static final int JOURNAL_MISMATCH_CODE = 32;
   static final int PROTOCOL_VIOLATION = 33;
 
+  @SuppressWarnings("StaticAssignmentOfThrowable")
   static final ProtocolException CLOSED = new ProtocolException("Invocation closed");
 
   private final int failureCode;

sdk-core-impl/src/main/java/dev/restate/sdk/core/impl/ReadyResultStateMachine.java

@@ -50,6 +50,7 @@ void onNewReadyResult(OnNewReadyResultCallback callback) {
     this.tryProgress(callback);
   }
 
+  @Override
   void abort(Throwable cause) {
     super.abort(cause);
     this.consumeCallback(this::tryProgress);

sdk-core-impl/src/main/java/dev/restate/sdk/core/impl/SyscallsImpl.java

@@ -203,7 +203,7 @@ public void exitSideEffectBlockWithException(
 
     // If it's a non-terminal exception (such as a protocol exception),
     // we don't write it but simply throw it
-    if (!(isTerminalException(toWrite))) {
+    if (!isTerminalException(toWrite)) {
       // For safety wrt Syscalls API we do this check and wrapping,
       // but with the current APIs the exception should always be RuntimeException
       // because that's what can be thrown inside a lambda

sdk-core-impl/src/test/java/dev/restate/sdk/core/impl/FlowUtils.java

@@ -60,20 +60,21 @@ public BufferedMockPublisher(Collection<T> elements) {
     @Override
     public void subscribe(Flow.Subscriber<? super T> subscriber) {
       subscriber.onSubscribe(
-          new MockSubscription<>(subscriber, new ArrayDeque<>(elements), subscriptionCancelled));
+          new BufferedMockSubscription<>(
+              subscriber, new ArrayDeque<>(elements), subscriptionCancelled));
     }
 
     public boolean isSubscriptionCancelled() {
       return subscriptionCancelled.get();
     }
 
-    private static class MockSubscription<T> implements Flow.Subscription {
+    private static class BufferedMockSubscription<T> implements Flow.Subscription {
 
       private final Flow.Subscriber<? super T> subscriber;
       private final Queue<T> queue;
       private final AtomicBoolean cancelled;
 
-      private MockSubscription(
+      private BufferedMockSubscription(
           Flow.Subscriber<? super T> subscriber,
           Queue<T> queue,
           AtomicBoolean subscriptionCancelled) {
@@ -105,11 +106,11 @@ public void cancel() {
 
   public static class UnbufferedMockPublisher<T> implements Flow.Publisher<T> {
 
-    private MockSubscription<T> subscription;
+    private UnbufferedMockSubscription<T> subscription;
 
     @Override
     public void subscribe(Flow.Subscriber<? super T> subscriber) {
-      this.subscription = new MockSubscription<>(subscriber);
+      this.subscription = new UnbufferedMockSubscription<>(subscriber);
       subscriber.onSubscribe(this.subscription);
     }
 
@@ -125,15 +126,15 @@ public void close() {
       Objects.requireNonNull(this.subscription).onClose();
     }
 
-    private static class MockSubscription<T> implements Flow.Subscription {
+    private static class UnbufferedMockSubscription<T> implements Flow.Subscription {
 
       private final Flow.Subscriber<? super T> subscriber;
       private final Queue<T> queue;
       private boolean publisherClosed = false;
       private long request = 0;
       private boolean cancelled = false;
 
-      private MockSubscription(Flow.Subscriber<? super T> subscriber) {
+      private UnbufferedMockSubscription(Flow.Subscriber<? super T> subscriber) {
         this.subscriber = subscriber;
         this.queue = new ArrayDeque<>();
       }

sdk-core-impl/src/test/java/dev/restate/sdk/core/impl/TestDefinitions.java

@@ -120,6 +120,7 @@ public static class WithInputBuilder extends TestInvocationBuilder {
       this.input = new ArrayList<>(input);
     }
 
+    @Override
     public WithInputBuilder withInput(MessageLiteOrBuilder... messages) {
       if (this.invalidReason == null) {
         this.input.addAll(

sdk-core/src/main/java/dev/restate/sdk/core/InvocationId.java

@@ -10,9 +10,12 @@
  */
 public interface InvocationId {
 
+  /** gRPC {@link Context} key for invocation id. */
   Context.Key<InvocationId> INVOCATION_ID_KEY = Context.key("restate.dev/service_invocation_id");
 
-  /** Retrieves the current invocation id from the current gRPC {@link Context}. */
+  /**
+   * @return the current invocation id from the current gRPC {@link Context}.
+   */
   static InvocationId current() {
     return INVOCATION_ID_KEY.get();
   }

sdk-core/src/main/java/dev/restate/sdk/core/syscalls/DeferredResult.java

@@ -6,7 +6,9 @@ public interface DeferredResult<T> {
 
   boolean isCompleted();
 
-  /** Null if {@link #isCompleted()} is false. */
+  /**
+   * @return {@code null} if {@link #isCompleted()} is false.
+   */
   @Nullable
   ReadyResult<T> toReadyResult();
 }

sdk-http-vertx/src/main/java/dev/restate/sdk/http/vertx/RequestHttpServerHandler.java

@@ -169,7 +169,7 @@ private Executor blockingExecutor(String serviceName, Context currentContext) {
 
   private void handleDiscoveryRequest(HttpServerRequest request) {
     // Request validation
-    if (request.method() != HttpMethod.POST) {
+    if (!request.method().equals(HttpMethod.POST)) {
       request.response().setStatusCode(METHOD_NOT_ALLOWED.code()).end();
       return;
     }

sdk-java-blocking/src/test/java/dev/restate/sdk/blocking/AwakeableIdTest.java

@@ -23,6 +23,7 @@ public void greet(GreetingRequest request, StreamObserver<GreetingResponse> resp
     }
   }
 
+  @Override
   protected BindableService returnAwakeableId() {
     return new ReturnAwakeableId();
   }

sdk-java-blocking/src/test/java/dev/restate/sdk/blocking/SleepTest.java

@@ -19,7 +19,7 @@ private static class SleepGreeter extends GreeterGrpc.GreeterImplBase
     public void greet(GreetingRequest request, StreamObserver<GreetingResponse> responseObserver) {
       RestateContext ctx = restateContext();
 
-      ctx.sleep(Duration.ofMillis(1000));
+      ctx.sleep(Duration.ofSeconds(1));
 
       responseObserver.onNext(GreetingResponse.newBuilder().setMessage("Hello").build());
       responseObserver.onCompleted();
@@ -40,7 +40,7 @@ public void greet(GreetingRequest request, StreamObserver<GreetingResponse> resp
       List<Awaitable<?>> collectedAwaitables = new ArrayList<>();
 
       for (int i = 0; i < 10; i++) {
-        collectedAwaitables.add(ctx.timer(Duration.ofMillis(1000)));
+        collectedAwaitables.add(ctx.timer(Duration.ofSeconds(1)));
       }
 
       Awaitable.all(

sdk-testing/src/main/java/dev/restate/sdk/testing/TestRestateRuntime.java

@@ -125,6 +125,7 @@ private void handle(
     serviceInvocationStateMachineHandler.start();
   }
 
+  @SuppressWarnings("unchecked")
   private Object extractKey(
       String serviceName, String methodName, Protocol.PollInputStreamEntryMessage message) {
     LOG.debug("Extracting key for service {} and method {}", serviceName, methodName);
@@ -392,6 +393,7 @@ private void routeMessage(MessageLite t) {
       }
     }
 
+    @SuppressWarnings("FutureReturnValueIgnored")
     public void handleInvokeEntryMessage(Protocol.InvokeEntryMessage msg) {
       String invocationId = UUID.randomUUID().toString();
       CompletableFuture<? super MessageLite> future = new CompletableFuture<>();
@@ -417,6 +419,7 @@ public void handleInvokeEntryMessage(Protocol.InvokeEntryMessage msg) {
           Protocol.PollInputStreamEntryMessage.newBuilder().setValue(msg.getParameter()).build());
     }
 
+    @SuppressWarnings("FutureReturnValueIgnored")
     public void handleAwakeableEntryMessage() {
       CompletableFuture<? super MessageLite> future = new CompletableFuture<>();
       future.handle(