Currently using reddison, creating a redissonClient and trying to poll data from redis server. I can see the data in the redis db if I check via redis-cli but when I look at the string value in my java application it is always the first 8 characters of the string and no more. Not sure why it won't give me the whole value.
I've tried using the .peek() method as well and I see the same symptom in that I only get 8 characters of the string returned.
Here is the main part of the code I can provide more details as needed:
#Service
#Slf4j
public class RedisConsumer {
RedisConfig redisConfig;
//RQueue<String> redisQueue;
RBlockingQueue<String> redisQueue;
#Autowired
RedisConsumer(RedisConfig redisConfig) {
this.redisConfig = redisConfig;
}
public void pollAuditQueue() {
//Redisson
redisQueue.add("{JSON string here snipped out for brevity}");
String item = redisQueue.poll();
if (!Objects.isNull(item)) {
log.info("I found this item: " + item);
} else {
log.info("Nothing in queue...");
}
}
#PostConstruct
private void init() throws Exception {
RedissonClient redissonClient = redisConfig.redisson();
redisQueue = redissonClient.getBlockingQueue("test");
while(true) {
pollAuditQueue();
Thread.sleep(5000);
}
}
When I look at the print statement in my console I see:
I found this item: {"AuditEv
When I check the redis-cli I can see the whole value:
1) "\xfc\t{\"AuditEvent\":{\"timestamp\":\"2018-11-27 04:31:47.818000+0000\" snipped the rest out for brevity}"
Lastly if I check that the item was removed from Redis after being polled in the Java app I can confirm that it is.
Any help would be great since it's not throwing any specific error I'm not finding any resources online to help address it.
I've found one thing I didn't notice in my earlier testing. When I manually insert using the redis cli I was replicating what my first tests through Java did which put the \xfc\t at the front which can be seen in my sample above.
Just now when I used redisQueue.add from within my application I noticed in redis it has \xfc\x80\x90\x01 instead and those do return the entire string to me in my application. I assume then this has to do with memory allocation somehow? I'm marking the question as resolved as I am no longer experiencing the issue. If anyone can drop on comment on what those letter/numbers mean though it may be meaningful for anyone that reads this post later. Once I have researched it I will add that comment myself if no one has beat me to it!
Add encoding:
RMap map = redisson.getMap("SessionMap"); -->
RMap map = redisson.getMap("SessionMap", new StringCodec("UTF-8"));
Related
I'm trying to use Quarkus MP-Metrics. In a simple API I have a gauge as follows:
#Path("/count")
#GET
#Gauge(unit = MetricUnits.NONE, name = "customersNumberGauge", description = "Number of customers in the inventory")
public int getCustomersNumber()
{
return customerService.getCustomers().size();
}
I also have a couple of unit tests, for example:
#Test
public void testGetCustomerById()
{
get("/customers/1").then().statusCode(200).body("firstName", equalTo("Robert"));
assertMetricValue("fr.simplex_software.aws.lambda.quarkus.CustomerResource.customerByIdCount", 1);
get("/customers/1").then().statusCode(200).body("firstName", equalTo("Robert"));
assertMetricValue("fr.simplex_software.aws.lambda.quarkus.CustomerResource.customerByIdCount", 2);
}
which fails with the exception:
java.lang.IllegalArgumentException: A metric with metricID MetricID{name='fr.simplex_software.aws.lambda.quarkus.CustomerResource.customersNumberGauge', tags=[]} already exists
If I comment out the #Gauge annotation everything works fine. It's worth noting that, by doing that, I'm following exactly the Quarkus quick starts.
Many thanks for any help.
Kind regards,
Seymour
I have the following Akka actor:
public class MyActor extends AbstractActor {
protected Logger log = LoggerFactory.getLogger(this.getClass());
#Override
public Receive createReceive() {
return receiveBuilder()
.matchAny(message -> {
String myFullName = self().path().toString();
String myName = self().path().name();
ActorRef reincarnatedMe = context().actorFor(self().path().name());
String reincarnatedFullName = reincarnatedMe.path().toString();
String reincarnatedName = reincarnatedMe.path().name();
log.info("myFullName: {}", myFullName);
log.info("myName: {}", myName);
log.info("reincarnatedFullName: {}", reincarnatedFullName);
log.info("reincarnatedName: {}", reincarnatedName);
}).build();
}
}
At runtime it produces this output:
05:43:14.617 [MySystem-akka.actor.default-dispatcher-4] INFO myapp.actors.MyActor - myFullName: akka://MySystem/user/MyActor
05:43:14.623 [MySystem-akka.actor.default-dispatcher-4] INFO myapp.actors.MyActor - myName: MyActor
05:43:14.623 [MySystem-akka.actor.default-dispatcher-4] INFO myapp.actors.MyActor - reincarnatedFullName: akka://MySystem/user/MyActor/MyActor
05:43:14.623 [MySystem-akka.actor.default-dispatcher-4] INFO myapp.actors.MyActor - reincarnatedName: MyActor
My understanding was that context().actorFor(...) doesn't create a new actor, rather it finds an existing actor that matches the path/string you provide and returns a reference to it.
However, it appears that in my code above, self() becomes the parent of reincarnatedMe as evidenced by myFullName simply being "MySystem/user/MyActor" whereas reincarnatedFullName is "MySystem/user/MyActor/MyActor"...
Am I reading this right? If so, how can I invoke context().actorFor(...) (or any other method for that matter) such that myFullName becomes the same as reincarnatedFullName (so that self() and reincarnatedMe reference the same actor? And if I'm not reading this right, why is myFullName different than reincarnatedFullName?
Update:
public class AnotherActor extends AbstractActor { ... }
// Inside MyActor#createReceive:
ActorSelection anotherActorSel = context().actorSelection("AnotherActor");
anotherActorSel.tell(new SomeMessage(), self());
First, ActorContext.actorFor(String) is deprecated in favor of ActorContext.actorSelection(String). This method returns an ActorSelection, but you can still send a message to an ActorSelection (such as an Identify, which response with an ActorIdentity message automatically).
The documentation for the actorFor method says that, "Absolute URIs like akka://appname/user/actorA are looked up as described for look-ups by actorOf(ActorPath)." I can't find documentation on an actorOf(ActorPath) method, but the other actorOf methods state they create new actors, so I suspect this does the same. The behavior you've found is likely the reason for the deprecation -- or because it was deprecated and the methods used for something else.
After reading about the remote shell in the Spring Boot documentation I started playing around with it. I implemented a new Command that produces a Stream of one of my database entities called company.
This works fine. So I want to output my stream of companies in the console. This is done by calling toString() by default. While this seams reasonable there is also a way to get nicer results by using a Renderer.
Implementing one should be straight forward as I can delegate most of the work to one of the already existing ones. I use MapRenderer.
class CompanyRenderer extends Renderer<Company> {
private final mapRenderer = new MapRenderer()
#Override Class<Company> getType() { Company }
#Override LineRenderer renderer(Iterator<Company> stream) {
def list = []
stream.forEachRemaining({
list.add([id: it.id, name: it.name])
})
return mapRenderer.renderer(list.iterator())
}
}
As you can see I just take some fields from my entity put them into a Mapand then delegate to a instance of MapRenderer to do the real work.
TL;DR
Only problem is: How do I register my Renderer with CRaSH?
Links
Spring Boot documentation http://docs.spring.io/spring-boot/docs/current/reference/html/production-ready-remote-shell.html
CRaSH documentation (not helping) http://www.crashub.org/1.3/reference.html#_renderers
I'm coding in IntelliJ IDEA. When debugging my application, I can't use some default method implementations in Watches.
Here is a condensed example:
public class Friendship {
interface Friend {
default void sayHiTo(Friend friend) {
System.out.println("Hi, " + friend.hashCode());
}
default int amountOfHands() {
return 2;
}
}
public static class BasicFriend implements Friend {
int numberOfFaces() {
return 1;
}
}
public static void main(String[] args) {
System.out.println("Put a breakpoint here");
}
}
In main() method I put a breakpoint and set up three watches:
// Default interface method with dependency
new BasicFriend().sayHiTo(new BasicFriend())
// Default interface method without dependency
new BasicFriend().amountOfHands()
// Class method
new BasicFriend().numberOfFaces()
The first watch throws NoSuchMethodException complaining that method Friendship$BasicFriend.sayHiTo() doesn't exist.
The second watch runs successfully, but strangely it reports a boxed object
{java.lang.Integer#537} "2" instead of just a primitive 2.
The third watch reports a primitive 1, just as expected.
Why is the first watch not working? Is this a bug? Is this actually IDE related? Is it because of some conceptual flaw of default methods? Should it be working as I want it to in the first place? Is the strange result of the second watch somehow related to the issue in the first watch?
Prior to JDK 8u40, default and static interface methods were not supported by JDI (Java Debugger Interface), JDWP (Java Debugger Wire Protocol) and JDB (the standard Java debugger). This is bug JDK-8042123, which is recorded as fixed in 8u40 and a corresponding blurb appears in the 8u40 release notes.
Update to 8u40 or later to fix this issue, at least on the JDK side.
From the bug description, it looks like debugger-side changes are also required, to avoid casting com.sun.jdi.InterfaceType objects to com.sun.jdi.ClassType, but instead call InterfaceType.invokeMethod() directly.
In the specific case of IntelliJ, Suseika confirmed in a comment that 14.1.2 has mostly fixed the issue (except the unexpected boxing), though Mike Kobit still experiences this problem on that version with a ClassCastException suggestive of the incorrect cast above.
I'm new to Google's Guava library and am interested in Guava's Caching package. Currently I have version 10.0.1 downloaded. After reviewing the documentation, the JUnit tests source code and even after searching google extensively, I still can't figure out how to use the Caching package. The documentation is very short, as if it was written for someone who has been using Guava's library not for a newbie like me. I just wish there are more real world examples on how to use Caching package propertly.
Let say I want to build a cache of 10 non expiring items with Least Recently Used (LRU) eviction method. So from the example found in the api, I build my code like the following:
Cache<String, String> mycache = CacheBuilder.newBuilder()
.maximumSize(10)
.build(
new CacheLoader<String, String>() {
public String load(String key) throws Exception {
return something; // ?????
}
});
Since the CacheLoader is required, I have to include it in the build method of CacheBuilder. But I don't know how to return the proper value from mycache.
To add item to mycache, I use the following code:
mycache.asMap().put("key123", "value123");
To get item from mycache, I use this method:
mycache.get("key123")
The get method will always return whatever value I returned from CacheLoader's load method instead of getting the value from mycache. Could someone kindly tell me what I missed?
Guava's Cache type is generally intended to be used as a computing cache. You don't usually add values to it manually. Rather, you tell it how to load the expensive to calculate value for a key by giving it a CacheLoader that contains the necessary code.
A typical example is loading a value from a database or doing an expensive calculation.
private final FooDatabase fooDatabase = ...;
private final LoadingCache<Long, Foo> cache = CacheBuilder.newBuilder()
.maximumSize(10)
.build(new CacheLoader<Long, Foo>() {
public Foo load(Long id) {
return fooDatabase.getFoo(id);
}
});
public Foo getFoo(long id) {
// never need to manually put a Foo in... will be loaded from DB if needed
return cache.getUnchecked(id);
}
Also, I tried the example you gave and mycache.get("key123") returned "value123" as expected.