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why jpa not save data at a time

i want save data and check the data after call save method
but the value is not present in same request
i have two method depend each other
the two function communcation with each other by kafka
the first method save the data and after save using jpa call second method
find the recourd from database using jpa
and check the instanse using isPresent()
but in the second method i cant find the data save
but after this request i can find data
return exciption NoSuchElement
Try out several ways like:
1-use flush and saveAndFlush
2-sleep method 10000 milsec
3-use entityManger with #Transactional
but all of them not correct
i want showing you my two method from code:
i have producer and consumer
and this is SaveOrder method (first method):
note : where in the first method have all ways i used
#PersistenceContext
private EntityManager entityManager;
#Transactional
public void saveOrder(Long branchId,AscOrderDTO ascOrderDTO) throws Exception {
ascOrderDTO.validation();
if (ascOrderDTO.getId() == null) {
ascOrderDTO.setCreationDate(Instant.now());
ascOrderDTO.setCreatedBy(SecurityUtils.getCurrentUserLogin().get());
//add user
ascOrderDTO.setStoreId(null);
String currentUser=SecurityUtils.getCurrentUserLogin().get();
AppUser appUser=appUserRepository.findByLogin(currentUser);
ascOrderDTO.setAppUserId(appUser.getId());
}
log.debug("Request to save AscOrder : {}", ascOrderDTO);
AscOrder ascOrder = ascOrderMapper.toEntity(ascOrderDTO);
//send notify to branch
if(!branchService.orderOk())
{
throw new BadRequestAlertException("branch not accept order", "check order with branch", "branch");
}
ascOrder = ascOrderRepository.save(ascOrder);
/*
* log.debug("start sleep"); Thread.sleep(10000); log.debug("end sleep");
*/
entityManager.setFlushMode(FlushModeType.AUTO);
entityManager.flush();
entityManager.clear();
//ascOrderRepository.flush();
try {
producerOrder.addOrder(branchId,ascOrder.getId(),true);
stateMachineHandler.stateMachine(OrderEvent.EMPTY, ascOrder.getId());
stateMachineHandler.handling(ascOrder.getId());
//return ascOrderMapper.toDto(ascOrder);
}
catch (Exception e) {
// TODO: handle exception
ascOrderRepository.delete(ascOrder);
throw new BadRequestAlertException("cannot deliver order to Branch", "try agine", "Try!");
}
}
in this code go to producer :
producerOrder.addOrder(branchId,ascOrder.getId(),true);
and this is my producer:
public void addOrder(Long branchId, Long orderId, Boolean isAccept) throws Exception {
ObjectMapper obj = new ObjectMapper();
try {
Map<String, String> map = new HashMap<>();
map.put("branchId", branchId.toString());
map.put("orderId", orderId.toString());
map.put("isAccept", isAccept.toString());
kafkaTemplate.send("orderone", obj.writeValueAsString(map));
}
catch (Exception e) {
throw new Exception(e.getMessage());
}
}
and in this code go to consumer:
kafkaTemplate.send("orderone", obj.writeValueAsString(map));
this is my consumer:
#KafkaListener(topics = "orderone", groupId = "groupId")
public void processAddOrder(String mapping) throws Exception {
try {
log.debug("i am in consumer add Order");
ObjectMapper mapper = new ObjectMapper(); Map<String, String> result = mapper.readValue(mapping,
HashMap.class);
branchService.acceptOrder(Long.parseLong(result.get("branchId")),Long.parseLong(result.get("orderId")),
Boolean.parseBoolean(result.get("isAccept")));
log.debug(result.toString());
}
catch (Exception e) {
throw new Exception(e.getMessage());
}
}
**and this code go to AcceptOrder (second method) : **
branchService.acceptOrder(Long.parseLong(result.get("branchId")),Long.parseLong(result.get("orderId")),
Boolean.parseBoolean(result.get("isAccept")));
this is my second method :
public AscOrderDTO acceptOrder(Long branchId, Long orderId, boolean acceptable) throws Exception {
ascOrderRepository.flush();
try {
if (branchId == null || orderId == null || !acceptable) {
throw new BadRequestAlertException("URl invalid query", "URL", "Check your Input");
}
if (!branchRepository.findById(branchId).isPresent() || !ascOrderRepository.findById(orderId).isPresent()) {
throw new BadRequestAlertException("cannot find branch or Order", "URL", "Check your Input");
}
/*
* if (acceptable) { ascOrder.setStatus(OrderStatus.PREPARING); } else {
* ascOrder.setStatus(OrderStatus.PENDING); }
*/
Branch branch = branchRepository.findById(branchId).get();
AscOrder ascOrder = ascOrderRepository.findById(orderId).get();
ascOrder.setDiscount(50.0);
branch.addOrders(ascOrder);
branchRepository.save(branch);
log.debug("///////////////////////////////Add order sucess////////////////////////////////////////////////");
return ascOrderMapper.toDto(ascOrder);
} catch (Exception e) {
// TODO: handle exception
throw new Exception(e.getMessage());
}
}

Adding Thread.sleep() inside saveOrder makes no sense.
processAddOrder executes on a completely different thread, with a completely different persistence context. All the while, your transaction from saveOrder might still be ongoing, with none of the changes made visible to other transactions.
Try splitting saveOrder into a transactional method and sending the notification, making sure that the transaction ends before the event handling has a chance to take place.
(Note that this approach introduces at-most-once semantics. You have been warned)

Manually acknowledge Kafka Event A consuming after producing event B

I have a case where I have to consume event A and do some processing, then produce the event B. So my problem is what would happen is the processing crashed and the application couldn't produce B while it consumed already A. My approach is to acknowledge after successfully publishing B, am I correct or should implement another solution for this case?
#KafkaListener(
id = TOPIC_ID,
topics = TOPIC_ID,
groupId = GROUP_ID,
containerFactory = LISTENER_CONTAINER_FACTORY
)
public void listen(List<Message<A>> messages, Acknowledgment acknowledgment) {
try {
final AEvent aEvent = messages.stream()
.filter(message -> null != message.getPayload())
.map(Message::getPayload)
.findFirst()
.get();
processDao.doSomeProcessing() // returns a Mono<Example> by calling an externe API
.subscribe(
response -> {
ProducerRecord<String, BEvent> BEventRecord = new ProducerRecord<>(TOPIC_ID, null, BEvent);
ListenableFuture<SendResult<String, BEvent>> future = kafkaProducerTemplate.send(buildBEvent());
future.addCallback(new ListenableFutureCallback<SendResult<String, BEvent>>() {
#Override
public void onSuccess(SendResult<String, BEvent> BEventSendResult) {
//TODO: do when event published successfully
}
#Override
public void onFailure(Throwable exception) {
exception.printStackTrace();
throw new ExampleException();
}
});
},
error -> {
error.printStackTrace();
throw new ExampleException();
}
);
acknowledgment.acknowledge(); // ??
} catch (ExampleException) {
exception.printStackTrace();
}
}

You can't manage kafka "acknowledgments" when using async code such as reactor.
Kafka does not manage discrete acks for each topic/partition, just the last committed offset for the partition.
If you process two records asynchronously, you will have a race as to which offset will be committed first.
You need to perform the sends on the listener container thread to maintain proper ordering.

Many-to-One records Kafka Streams

I would like to turn many records into one per message. I tried many things like custom reducing and aggregators, but they all still send one-to-one records back out. For example I would like to convert many strings into just one string. If my stream is messages with the same key, but different values, "the", "sky", "is", "blue", then I would like to outback back one concatenation of them in a new topic "the,sky,is,blue,". What I am instead getting is 4 messages "the,", "the, sky,", "the,sky, is,", "the,sky,is,blue,". When I send a second message to the kafka consumer, it will concatenate on the previous aggregation and I eventually receive this "the,sky,is,blue,the,sky,is,blue,"
I also tried using a custom storebuilder and changing a lot of the settings to see if that would do anything.
Map<String, String> changelogConfig = new HashMap<>();
changelogConfig.put("message.down.conversion.enable", "true");
changelogConfig.put("flush.messages", "0");
changelogConfig.put("flush.ms", "0");
StoreBuilder<KeyValueStore<String, String>> aggStoreSupplier = Stores.keyValueStoreBuilder(
Stores.persistentKeyValueStore("AggStore"),
Serdes.String(),
Serdes.String())
.withLoggingEnabled(changelogConfig);
KStream<String, String> results = source // single message get processed and eventually i get these string results I need to concatenate
.groupByKey() // this kgroupedstream has the N records, which was how many were sent in the message
.reduce(new Reducer<String>() {
#Override
public String apply(String aggValue, String value) {
return value + "," + aggValue;
}
}, Materialized.as("AggStore"))
.toStream();
results.to("results", Produced.with(Serdes.String(), Serdes.String()));
final Topology topology = builder.build(); // to describe topology
System.out.println(topology.describe()); // to print description
final KafkaStreams streams = new KafkaStreams(topology, props);
final CountDownLatch latch = new CountDownLatch(1);
// attach shutdown handler to catch control-c
Runtime.getRuntime().addShutdownHook(new Thread("streams-shutdown-hook") {
#Override
public void run() {
streams.close();
latch.countDown();
}
});
try {
streams.cleanUp();
streams.start();
latch.await();
} catch (Throwable e) {
System.exit(1);
}
System.exit(0);

CodenameOne Connection Request wait postResponse

i've done a rest web service that gives me some contact information like numbers, age ... i get all this information in this function
public static void getRest(String search) {
if(search.equals("")){
json="http://localhost:8080/com.vogella.jersey.first/rest/jsonServices/print/";
} else {
json="http://localhost:8080/com.vogella.jersey.first/rest/jsonServices/print/"+search;
}
ConnectionRequest req = new ConnectionRequest() {
#Override
protected void postResponse() {
}
#Override
protected void readResponse(InputStream input) throws IOException {
JSONParser p = new JSONParser();
Map<String, Object> h = p.parseJSON(new InputStreamReader(input));
ArrayList object=new ArrayList();
for (Entry<String, Object> entry : h.entrySet()) {
object = (ArrayList) entry.getValue();
int i=object.size();
}
for(int i=0; i<object.size();i++){
LinkedHashMap s= (LinkedHashMap) object.get(i);
Risultati.add(s);
}
}
};
req.setUrl(json);
req.setPost(false);
req.addRequestHeader("Accept", "application/json");
InfiniteProgress prog = new InfiniteProgress();
Dialog dlg = prog.showInifiniteBlocking();
req.setDisposeOnCompletion(dlg);
NetworkManager.getInstance().addToQueue(req);
Risultati is an attribute of the class: ArrayList<LinkedHashMap> Risultati;
the problem is that when i call the function getRest("") in this way:
getRest("");
Label contatto=null;
for(int j=0;j<Risultati.size();j++){
LinkedHashMap s=Risultati.get(j);
String nome=(String) s.get("firstName");
String cognome=(String) s.get("lastName");
String numero =(String) s.get("numero");
contatto=new Label(nome+" "+cognome+" "+numero);
}
hi.addComponent(contatto);
it turns that Risultati is null, if i comment the for cycle i notice that the inner function readResponse is executed after...i don't know what i'm doing wrong

I think the point is that you're calling NetworkManager.getInstance().addToQueue(req). According to it's documentation, it will add a connection request (the one you've just created) to a queue. After the connection request is added to the queue, it returns, meaning the request may or may not have been executed by that time.
You have to options to deal with this. In my opinion, the best way would be to update the user interface after the request has completed, as described in the "File System, Storage, Network & Parsing" chapter of the CodeOne manual:
req.addResponseListener(new ActionListener() {
public void actionPerformed(ActionEvent ev) {
NetworkEvent e = (NetworkEvent)ev;
// ... process the response
}
});
Alternatively, you could replace the call to addToQueue(req) with addToQueueAndWait(req). The latter method waits until the request is processed in the queue. The downside of the latter approach is that your user interface may freeze while the request is being processed, because the UI thread is blocked on the network I/O.

How to send custom graph data to MCStats every hour?

I have been working on a plugin and have gotten some really interesting data with it, I am trying to add a custom graph and have succeeded on getting the graph to appear with the name I set in code on MCStats.
My plugin is here and recreates the Dense Ores Mod.
I would like to send block mined data on an hourly basis. This is what I have in my onEnable so far:
try {
Metrics metrics = new Metrics(this);
Graph blocksMinedGraph = metrics.createGraph("Extra items from blocks");
blocksMinedGraph.addPlotter(new Metrics.Plotter("Coal Ore") {
#Override
public int getValue() {
return coalMined;
}
});
blocksMinedGraph.addPlotter(new Metrics.Plotter("Iron Ore") {
#Override
public int getValue() {
return ironMined;
}
});
metrics.start();
} catch (IOException e) {
getLogger().info(ANSI_RED + "Metrics have been unable to load for: DenseOres" + ANSI_RESET);
}
This has successfully created a new graph on my MCStats page called 'Extra items from blocks' although I have been unable to populate it thus far. I have tried but cannot work out how to send the data.
Connected to this question, when sending the data, will I have to keep a count of the values in a file somewhere so they persist between reloads and server restarts?

I appear to have solved it by placing the blocksMinedGraph.addPlotter(...) parts in an async repeating task.
Here is the code with the repeating task in place, the graphs on MCStats take forever to update though.
try {
Metrics metrics = new Metrics(this);
if (!metrics.isOptOut()) {
final Graph blocksMinedGraph = metrics.createGraph("Extra items from blocks (Since v2.3)");
Bukkit.getScheduler().runTaskTimerAsynchronously(this, new Runnable() {
public void run() {
getLogger().info("Graph data sent");
blocksMinedGraph.addPlotter(new Metrics.Plotter("Coal Ore") {
#Override
public int getValue() {
return coalMined;
}
});
blocksMinedGraph.addPlotter(new Metrics.Plotter("Iron Ore") {
#Override
public int getValue() {
return ironMined;
}
});
}
}, DELAY, INCREMENT);
getLogger().info("Metrics started");
metrics.start();
}
} catch (IOException e) {
getLogger().info(ANSI_RED + "Metrics have been unable to load for: DenseOres" + ANSI_RESET);
}