Akka Typed context.messageAdapter does not manage responses correctly - akka-typed

I'm trying to migrate a personal project from Akka Classic to Akka Typed and I'm having some troubles with messageAdapters.
Here below the code to reproduce the behavior that is causing me some troubles:
object Example extends App {
val system = ActorSystem(MyActor(), "system")
system ! MyActor.Msg("Foo") // 3 chars lenght
system ! MyActor.Msg("FooBarOsdAsd") // 12 chars lenght
object MyActor {
sealed trait Command
case class Msg(payload: String) extends Command
case class Question(payload: String, replyTo: ActorRef[Response]) extends Command
case class WrappedResponseOne(response: Response) extends Command
case class WrappedResponseTwo(response: Response) extends Command
sealed trait Response
case object Yes extends Response
case object No extends Response
def apply(): Behavior[Command] =
Behaviors.setup { context =>
new MyActor(context).stateless()
// I need to have a private class that implement a method to expose the wanted behavior
private class MyActor(context: ActorContext[MyActor.Command]) {
// This is the adapter I want to use
private val wrappedOne: ActorRef[MyActor.Response] =
// This variable is unused
private val wrappedTwo: ActorRef[MyActor.Response] =
def stateless(): Behaviors.Receive[MyActor.Command] = Behaviors.receiveMessage[MyActor.Command] {
case MyActor.Msg(payload) =>
context.self ! MyActor.Question(payload, wrappedOne)
case MyActor.Question(payload, replyTo) =>
if (payload.length > 10) replyTo ! MyActor.No else replyTo ! MyActor.Yes
case MyActor.WrappedResponseOne(response) =>
response match {
case MyActor.Yes =>
case MyActor.No =>
case msg =>
Here I'm defining two messageAdapters: wrappedOne and wrappedTwo. When the actor got a MyActor.Msg I want that the responses will be handled by wrappedOne (leaving wrappedTwo completely unused). I can't get why my code let wrappedTwo manage the responses. Here below is the output from the console.
SLF4J: See also http://www.slf4j.org/codes.html#substituteLogger
22:57:38.879 [system-akka.actor.default-dispatcher-3] DEBUG exlude.ActorAdapter$MyActor - Foo
22:57:38.881 [system-akka.actor.default-dispatcher-3] DEBUG exlude.ActorAdapter$MyActor - FooBarOsdAsd
22:57:38.890 [system-akka.actor.default-dispatcher-3] DEBUG exlude.ActorAdapter$MyActor - WrappedResponseTwo(Yes)
22:57:38.891 [system-akka.actor.default-dispatcher-3] DEBUG exlude.ActorAdapter$MyActor - WrappedResponseTwo(No)
22:57:38.904 [system-akka.actor.default-dispatcher-3] INFO akka.actor.LocalActorRef - Message [exlude.ActorAdapter$MyActor$WrappedResponseTwo] to Actor[akka://system/user] was unhandled. [1] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'.
22:57:38.907 [system-akka.actor.default-dispatcher-3] INFO akka.actor.LocalActorRef - Message [exlude.ActorAdapter$MyActor$WrappedResponseTwo] to Actor[akka://system/user] was unhandled. [2] dead letters encountered. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'.
Is there something wrong with how I'm defining the adapters?

That behavior is by design: only one message adapter for a given incoming message type can be registered at a time. This prevents unbounded growth in the number of adapters if (e.g.) the adapter is being registered in response to messages. The last adapter wins.
See docs and note that if A is a subclass of B, adapters for A and B can both be registered, but since the adapters are tested last-registered-first, if the B adapter is registered after the A adapter, it will shadow the A adapter.
For situations where there's at-most-one response per request, context.ask may be a better fit.
If you really need multiple adaptations of the same message types, spawning a child actor for each adaptation is probably the way to go; having to do this may be a sign that your messaging protocols could use a rethink.


GetNetworkType in Android 11

Following the changes posted here, the getNetworkType method is deprecated from Android R and onwards.
When trying to use this method in a R compiled application, results in the following exception being thrown:
java.lang.SecurityException: getDataNetworkTypeForSubscriber: uid 10225 does not have android.permission.READ_PHONE_STATE.
at android.os.Parcel.createExceptionOrNull(Parcel.java:2285)
at android.os.Parcel.createException(Parcel.java:2269)
at android.os.Parcel.readException(Parcel.java:2252)
at android.os.Parcel.readException(Parcel.java:2194)
at com.android.internal.telephony.ITelephony$Stub$Proxy.getNetworkTypeForSubscriber(ITelephony.java:7565)
at android.telephony.TelephonyManager.getNetworkType(TelephonyManager.java:2964)
at android.telephony.TelephonyManager.getNetworkType(TelephonyManager.java:2928)
at com.ironsource.environment.ConnectivityService.getCellularNetworkType(ConnectivityService.java:197)
at com.ironsource.sdk.service.DeviceData.updateWithConnectionInfo(DeviceData.java:98)
at com.ironsource.sdk.service.DeviceData.fetchMutableData(DeviceData.java:54)
at com.ironsource.sdk.service.TokenService.collectDataFromDevice(TokenService.java:120)
at com.ironsource.sdk.service.TokenService.getRawToken(TokenService.java:177)
at com.ironsource.sdk.service.TokenService.getToken(TokenService.java:166)
at com.ironsource.sdk.IronSourceNetwork.getToken(IronSourceNetwork.java:183)
This is fine and is expected according to the documentation. If I compile the application to any version before Android R, the exception doesn't show.
This exception indicates that I need to request the android.permission.READ_PHONE_STATE permission.
I wanted to know if there is a way to get the network type with any other API that does NOT require this permission (as this permission's level is dangerous and I would rather not ask the user for it).
Take runtime permission for READ_PHONE_STATE to ignore crash of getDataNetworkTypeForSubscriber
protected void onStart() {
int res = checkSelfPermission(android.Manifest.permission.READ_PHONE_STATE);
if (res != PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[]{android.Manifest.permission.READ_PHONE_STATE}, 123);
private final static int REQUEST_CODE_ASK_PERMISSIONS = 1002;
public void onRequestPermissionsResult(int requestCode,
#NonNull String[] permissions, #NonNull int[] grantResults) {
switch (requestCode) {
if (grantResults[0] != PackageManager.PERMISSION_GRANTED) {
Toast.makeText(getApplicationContext(), "READ_PHONE_STATE Denied", Toast.LENGTH_SHORT)
} else {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
You can still use getDataNetworkType(); This method does not necessarily need READ_PHONE_STATE, as stated in his Doc, but that it's sufficient "that the calling app has carrier privileges".
For what I know about getting those privigileges, it could be tricky/really hard, you may look into getting carrier privileges and using this method, which is also the suggested substitution for getNetworkType().
This method necessarily need READ_PHONE_STATE by this way in your activity not just manifest >>>
// Check if the READ_PHONE_STATE permission is already available.
!= PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.READ_PHONE_STATE)) {
//here >> use getNetworkType() method
// like this example
else {}
We can use ConnectivityManager#getNetworkCapabilities and NetworkCapablities#hasTransport like this
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkCapabilities caps = cm.getNetworkCapabilities(cm.getActivityNetwork());
boolean isMobile = caps.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR);
boolean isWifi = caps.hasTransport(NetworkCapabilities.TRANSPORT_WIFI);
This class was deprecated in API level 29. Callers should instead use the ConnectivityManager.NetworkCallback API
to learn about connectivity changes, or switch to use
ConnectivityManager#getNetworkCapabilities or
ConnectivityManager#getLinkProperties to get information
synchronously. Keep in mind that while callbacks are guaranteed to be
called for every event in order, synchronous calls have no such
constraints, and as such it is unadvisable to use the synchronous
methods inside the callbacks as they will often not offer a view of
networking that is consistent (that is: they may return a past or a
future state with respect to the event being processed by the
callback). Instead, callers are advised to only use the arguments of
the callbacks, possibly memorizing the specific bits of information
they need to keep from one callback to another.
So my friend I have the same trouble as you but so far I came with a temporary fix I use the compileSdkVersion 29 not 30 as well as the targetSdkVersion 29 and my buildToolsVersion 28.0.3 and my app is loading fine.
Since this problem by me its coming due a third party library so till the fix the error I can not fix it alone, but I think with this temporary solution for now is quite well.

How can I use bulkhead in feignClient?

1、Can I use bulkhead pattern in feignClient?
2、I have some confusion about hystrix.
For example,if I only have three feign clients "a","b","c"。The "a" calls "b" and "c".
I know I can easily use circuit breaker with fallback parameter and some Configuration like this:
#FeignClient(name = "b", fallback = bFallback.class)
protected interface HystrixClient {
//some methods
#FeignClient(name = "c", fallback = cFallback.class)
protected interface HystrixClient {
//some methods
In another way,I could use #HystrixCommand to wrap my remote call with some Configuration like this:
public Object get(#PathVariable("id") long id) {
In addition I can configure some parameter in #HystrixCommand or application.yml,and I also can add threadPoolKey in in #HystrixCommand
Q1:I have learn that Hystrix wrapped remote call to achieve purpose,I can understand on the latter way,but the former way likes wrapping callee?
I found in document that:
Feign will wrap all methods with a circuit break
Is this mean FeignClient seems adding #Hystrixcommand on every method in interface in essence?
Q2:If the Feign client "b" have three remote call,how can I let them run in bulkhead to avoid one method consuming all thread? to Combine the feignClient and #HystrixCommand? will them conflict?
Because I do not found the parameter likes threadPoolKey in feignClient. Auto bulkhead?
Q3:If my hystrix configuration is in application.yml ,the feignClient pattern and #HytirxCommand pattern whether have the same configuration pattern? like this:
but what's the follow Timeout?
connectTimeout: 5000
readTimeout: 5000
1、Can I use bulkhead pattern in feignClient?
Java doc of setterFactory() method of HystrixFeign class says:
* Allows you to override hystrix properties such as thread pools and command keys.
public Builder setterFactory(SetterFactory setterFactory) {
this.setterFactory = setterFactory;
return this;
https://cloud.spring.io/spring-cloud-netflix/multi/multi_spring-cloud-feign.html says:
Spring Cloud Netflix does not provide the following beans by default for feign, but still looks up beans of these types from the application context to create the feign client:
• Logger.Level
• Retryer
• ErrorDecoder
• Request.Options
• Collection
• SetterFactory
So we should create setterFactory and specifying thread pool there. You can create a Bean like this:
public SetterFactory feignHystrixSetterFactory() {
return (target, method) -> {
String groupKey = target.name();
String commandKey = Feign.configKey(target.type(), method);
return HystrixCommand.Setter
.andThreadPoolKey(HystrixThreadPoolKey.Factory.asKey( target.type().getSimpleName() ));
but what's the follow Timeout?
Feign client timeout is similar to ribbon timeout and specifies the properties of httpconnectin but you can define different timeouts for different feignclient.
feign.client.config.bar.readTimeout //this configuration will apply to bar client
feign.client.config.default.readTimeout // this configuration will apply to all feign
How did I found that? if you debug your application and put breakpoints on the following code of RetryableFeignLoadBalancer class:
final Request.Options options;
if (configOverride != null) {
RibbonProperties ribbon = RibbonProperties.from(configOverride);
options = new Request.Options(ribbon.connectTimeout(this.connectTimeout),
else {
options = new Request.Options(this.connectTimeout, this.readTimeout);
you will see these value will be used as properties of HTTPConection.pls have a look at feign.Client class.

How to execute blocking calls within a Spring Webflux / Reactor Netty web application

In my use case where I have a Spring Webflux microservice with Reactor Netty, I have the following dependencies:
org.springframework.boot.spring-boot-starter-webflux (2.0.1.RELEASE)
org.springframework.boot.spring-boot-starter-data-mongodb-reactive (2.0.1.RELEASE)
org.projectreactor.reactor-spring (1.0.1.RELEASE)
For a very specific case I need to retrieve some information from my Mongo database, and process this into query parameters send with my reactive WebClient. As the WebClient nor the UriComponentsBuilder accepts a Publisher (Mono / Flux) I used a #block() call to receive the results.
Since reactor-core (version 0.7.6.RELEASE) which has been included in the latest spring-boot-dependencies (version 2.0.1.RELEASE) it is not possible anymore to use: block()/blockFirst()/blockLast() are blocking, which is not supported in thread xxx, see -> https://github.com/reactor/reactor-netty/issues/312
My code snippet:
public Mono<FooBar> getFooBar(Foo foo) {
MultiValueMap<String, String> parameters = new LinkedMultiValueMap<>();
parameters.add("size", foo.getSize());
parameters.addAll("bars", barReactiveCrudRepository.findAllByIdentifierIn(foo.getBarIdentifiers()) // This obviously returns a Flux
String url = UriComponentsBuilder.fromHttpUrl("https://base-url/")
return webClient.get()
This worked with spring-boot version 2.0.0.RELEASE, but since the upgrade to version 2.0.1.RELEASE and hence the upgrade from reactor-core to version 0.7.6.RELEASE it is not allowed anymore.
The only real solution I see is to include a block (non-reactive) repository / mongo client as well, but I'm not sure if that is encouraged. Any suggestions?
The WebClient does not accept a Publisher type for its request URL, but nothing prevents you from doing the following:
public Mono<FooBar> getFooBar(Foo foo) {
Mono<List<String>> bars = barReactiveCrudRepository
Mono<FooBar> foobar = bars.flatMap(b -> {
MultiValueMap<String, String> parameters = new LinkedMultiValueMap<>();
parameters.add("size", foo.getSize());
parameters.addAll("bars", b);
String url = UriComponentsBuilder.fromHttpUrl("https://base-url/")
return webClient.get()
return foobar;
If anything, this new reactor-core inspection saved you from crashing your whole application with this blocking call in the middle of a WebFlux handler.

Hystrix Javanica : Call always returning result from fallback method.(java web app without spring)

I am trying to integrate Hystrix javanica into my existing java EJB web application and facing 2 issues with running it.
When I try to invoke following service it always returns response from fallback method and I see that the Throwable object in fallback method has "com.netflix.hystrix.exception.HystrixTimeoutException" exception.
Each time this service is triggered, HystrixCommad and fallback methods are called multiple times around 50 times.
Can anyone suggest me with any inputs? Am I missing any configuration?
I am including following libraries in my project.
project libraries
I have setup my aspect file as follows:
<weaver options="-verbose -showWeaveInfo"></weaver>
<aspect name="com.netflix.hystrix.contrib.javanica.aop.aspectj.HystrixCommandAspect"/>
Here is my config.properties file in META-INF/config.properties
Here is my rest service file
public class HystrixService {
#Produces({ MediaType.APPLICATION_JSON })
public Response getClusterName(#QueryParam("id") int id) {
ClusterCmdBean clusterCmdBean = new ClusterCmdBean();
String result = clusterCmdBean.getClusterNameForId(id);
return Response.ok(result).build();
Here is my bean class
public class ClusterCmdBean {
#HystrixCommand(groupKey = "ClusterCmdBeanGroup", commandKey = "getClusterNameForId", fallbackMethod = "defaultClusterName")
public String getClusterNameForId(int id) {
if (id > 0) {
return "cluster"+id;
} else {
throw new RuntimeException("command failed");
public String defaultClusterName(int id, Throwable e) {
return "No cluster - returned from fallback:" + e.getMessage();
Thanks for the help.
If you want to ensure you are setting the property, you can do that explicitly in the circuit annotation itself:
#HystrixCommand(commandProperties = {
#HystrixProperty(name = "execution.timeout.enabled", value = "false")
I would only recommend this for debugging purposes though.
Something that jumps out to me is that Javanica uses AspectJ AOP, which I have never seen work with new MyBean() before. I've always have to use #Autowired with Spring or similar to allow proxying. This could well just be something that is new to me though.
If you set a breakpoint inside the getClusterNameForId can you see in the stack trace that its being called via reflection (which it should be AFAIK)?
Note you can remove commandKey as this will default to the method name. Personally I would also remove groupKey and let it default to the class name.

Setting request timeout with Netflix Feign and Hystrix

I'm creating a REST client using Feign. I've got my calls working, but I want to add some timeout support, and I'm having a heck of a time figuring out how to do that.
Feign's documentation says "to use Hystrix with Feign, add the Hystrix module to your classpath. Then use the HystrixFeign builder." Ok, so now I've got this:
service = HystrixFeign.builder()
.decoder(new GsonDecoder())
.target(ProjectService.class, URL_TO_BE_MOVED_TO_PROPS);
Now all of my methods are returning HystrixCommands, which I can execute or queue, but I still can't see how to configure them.
The Hystrix wiki (https://github.com/Netflix/Hystrix/wiki/Configuration) says that configuration should be added into the HystrixCommand constructor like this:
public HystrixCommandInstance(int id) {
this.id = id;
But my commands are being built/return by Feign, so I don't have access to the constructors.
One more thing worth noting is that the Feign-Hystrix readme (https://github.com/Netflix/feign/tree/master/hystrix) says "To use Hystrix with Feign, add the Hystrix module to your classpath. Then, configure Feign to use the HystrixInvocationHandler," but a Google search for HystrixInvocationHandler points me toward a non-Netflix repo. Even if I used that, I don't see how to configure Feign to use it.
Please tell me I'm being dumb and that this is super simple, which will make me feel gladness that I'm past this issue, and shame for not being able to figure it out on my own.
TL;DR: I want to set timeouts on requests made by my Feign client. How do?
Turns out you can set Hystrix properties using an instance of com.netflix.config.ConfigurationManager (from com.netflix.archaius:archaius-core).
Feign uses method names as HystrixCommandKeys, so you can access their properties using those names:
ConfigurationManager.getConfigInstance().setProperty("hystrix.command." + methodName + ".execution.isolation.thread.timeoutInMilliseconds", 1500);
This is assuming you've used HystrixFeign to construct your client, which wraps each call in HystrixCommand objects.
To simplify, I created a loop of my methods so I could apply the timeout service-wide:
private void configureHystrix() {
Method[] methods = ProjectService.class.getMethods();
String methodName;
for(int i = 0; i < methods.length; i++) {
methodName = methods[i].getName();
ConfigurationManager.getConfigInstance().setProperty(String.format("hystrix.command.%s.execution.isolation.thread.timeoutInMilliseconds", methodName), config.getTimeoutInMillis());
After some debugging I managed to set Hystrix timeout as follows:
// copy-paste feign.hystrix.SetterFactory.Default, just add andCommandPropertiesDefaults
private SetterFactory getSetterFactory() {
return (target, method) -> {
String groupKey = target.name();
String commandKey = Feign.configKey(target.type(), method);
return HystrixCommand.Setter