Mongodb java驱动3.12.1中的MongoDB java连接

Question

我在 Ubuntu 18.04 中安装了 mongodb 4.0。 我正在使用 java-mongo-driver 3.12.1 我正在上传我的代码，您可以看到我检查了不同类型的连接，但它不起作用。

如何解决这个问题呢？

Answer 1

试试这个，让我知道你的想法......

package test;

public class Main {

    public static void main(String[] args) {
        com.mongodb.client.MongoClient client = connectToStandAlone();
        com.mongodb.client.MongoDatabase db = client.getDatabase("javatest");
        QueryData(db);
    }

    private static com.mongodb.client.MongoClient connectToStandAlone() {
        // STANDALONE STILL REQUIRES HOSTS LIST WITH ONE ELEMENT...

        java.util.ArrayList<com.mongodb.ServerAddress> hosts = new java.util.ArrayList<com.mongodb.ServerAddress>();
        hosts.add(new com.mongodb.ServerAddress("127.0.0.1", 27017));

        com.mongodb.MongoCredential mongoCredential = com.mongodb.MongoCredential.createScramSha1Credential("testuser", "admin", "mysecret".toCharArray());

        com.mongodb.MongoClientSettings mongoClientSettings = com.mongodb.MongoClientSettings.builder()
                .applyToClusterSettings(clusterSettingsBuilder -> clusterSettingsBuilder.hosts(hosts))
                .credential(mongoCredential)
                .writeConcern(com.mongodb.WriteConcern.W1)
                .readConcern(com.mongodb.ReadConcern.MAJORITY)
                .readPreference(com.mongodb.ReadPreference.nearest())
                .retryWrites(true)
                .build();

        com.mongodb.client.MongoClient client = com.mongodb.client.MongoClients.create(mongoClientSettings);

        return client;
    }

    private static void QueryData(com.mongodb.client.MongoDatabase db) {
        // DRIVER DOES NOT HAVE collection.findOne().

        com.mongodb.client.MongoCollection<org.bson.Document> collection = db.getCollection("people");
        com.mongodb.client.MongoCursor<org.bson.Document> cursor = collection.find(com.mongodb.client.model.Filters.eq("testfield", true))
            .sort(new org.bson.Document("review_date", -1))
            .skip(5)
            .limit(20)
            .iterator();

        while(cursor.hasNext()) {
            org.bson.Document document = cursor.next();
            String json = document.toJson();
            System.out.println(json);

            boolean testfieldValue = document.getBoolean("testfield");
            String ssnValue = document.getString("ssn");
        }
    }
}

Answer 2

我找到了简单的解决方案。 我添加了更多的 jar 文件，我们总共需要 (bson-3.12.1.jar, mongodb-driver-core-3.12.1.jar, mongodb-driver-sync-3.12.1.jar, mongodb-driver-sync- 3.12.1-javadoc.jar）。 这些可在此处输入链接描述中找到

现在我的代码工作正常

import com.mongodb.client.MongoClients;
import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;

import org.bson.Document;
import java.util.Arrays;



public class MongoConnection {

 public static void main(String[] args) {
    try {           
        // Create Connection
        MongoClient mongoClient = MongoClients.create("mongodb://localhost:27017");
        System.out.println("MongoDB connected successfully");

        //Accessing the database 
        MongoDatabase database = mongoClient.getDatabase("java");
        System.out.println("MongoDB database connection ");

        //Creating a collection 
        database.createCollection("first"); 
        System.out.println("Collection created successfully");

        //Accessing collection
        MongoCollection<Document> collection = database.getCollection("first");

        Document document = new Document("name", "Café Con Leche")
                   .append("contact", new Document("phone", "228-555-0149")
                                           .append("email", "cafeconleche@example.com")
                                           .append("location",Arrays.asList(-73.92502, 40.8279556)))
                   .append("stars", 3)
                   .append("categories", Arrays.asList("Bakery", "Coffee", "Pastries"));

        collection.insertOne(document);

    } catch (Exception e) {
        e.printStackTrace();
    }
 }
}