Example usage for com.mongodb.async.client MongoCollection countDocuments

Introduction

In this page you can find the example usage for com.mongodb.async.client MongoCollection countDocuments.

Prototype

void countDocuments(SingleResultCallback<Long> callback);

Source Link

Document

Counts the number of documents in the collection.

Usage

From source file:com.example.App.java

License:Apache License

public static void main(String[] args) throws InterruptedException {
    final MongoClientSettings settings = MongoClientSettings.builder()
            .addCommandListener(new CommandListener() {
                @Override//from   w  w w.ja va 2  s .  c o  m
                public void commandStarted(CommandStartedEvent event) {
                    logger.info("command: db = {}, command = {}", event.getDatabaseName(),
                            event.getCommandName());
                }

                @Override
                public void commandSucceeded(CommandSucceededEvent event) {
                    logger.info("command succeed: request = {}, command = {}", event.getRequestId(),
                            event.getCommandName());
                }

                @Override
                public void commandFailed(CommandFailedEvent event) {
                    logger.info("command failed: request = {}, command = {}", event.getRequestId(),
                            event.getCommandName());
                    logger.error("detail", event.getThrowable());
                }
            }).applicationName("sample-app")
            .applyToConnectionPoolSettings(builder -> builder.maxSize(1).minSize(1)).build();

    final MongoClient client = MongoClients.create(settings);
    final MongoDatabase database = client.getDatabase("sample");
    final MongoCollection<Document> collection = database.getCollection("test");

    final Document firstDocument = new Document("id", UUID.randomUUID()).append("name", "test user")
            .append("created", LocalDateTime.now());

    logger.info("document to be saved: {}", firstDocument);

    final Mono<Document> firstMono = Mono.create(sink -> collection.insertOne(firstDocument, (result, t) -> {
        if (t == null) {
            logger.info("inserted: {}", firstDocument);
            sink.success(firstDocument);
        } else {
            logger.error("error", t);
            sink.error(t);
        }
    }));

    final Mono<List<Document>> secondMono = create100Users(collection, firstMono);

    final Mono<Long> thirdMono = secondMono.then(Mono.create(sink -> collection.countDocuments((count, t) -> {
        if (t == null) {
            logger.info("collection has {} items.", count);
            sink.success(count);
        } else {
            logger.error("error", t);
            sink.error(t);
        }
    })));

    final Mono<List<Document>> fourthMono = create100Users(collection, thirdMono);
    final Mono<List<Document>> fifthMono = create100Users(collection, fourthMono);
    final Mono<List<Document>> sixthMono = create100Users(collection, fifthMono);

    final Mono<Document> seventhMono = sixthMono.then(Mono.create(sink -> collection.find().first((doc, t) -> {
        if (t == null) {
            logger.info("found document: {}", doc);
            sink.success(doc);
        } else {
            logger.error("error", t);
            sink.error(t);
        }
    })));

    final CountDownLatch latch = new CountDownLatch(1);
    seventhMono.doOnTerminate(() -> {
        latch.countDown();
        client.close();
    }).subscribe(doc -> logger.info("first document: {}", doc));
    latch.await();
}

---