MongoDB kezdés

Szerző: Sallai András
Copyright © 2023, Sallai András
Szerkesztve: 2024
Licenc: CC BY-SA 4.0
Web: https://szit.hu

Adatbázisok

String url = "mongodb://root:titok@localhost:27017";
 
ConnectionString cs = new ConnectionString(url);
MongoClient client = MongoClients.create(cs);
client.listDatabaseNames().forEach(System.out::println);

Teljes kód:

App.java

import com.mongodb.ConnectionString;
import com.mongodb.MongoException;
import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
 
public class App {
    public static void main(String[] args) throws Exception {
        try {
            String url = "mongodb://root:titok@localhost:27017";
 
            ConnectionString cs = new ConnectionString(url);
            MongoClient client = MongoClients.create(cs);
            client.listDatabaseNames().forEach(System.out::println);
        } catch (MongoException e) {
            System.err.println("Hiba! A kapcsolódás sikertelen!");
            System.err.println(e.getMessage());
        }
 
    }
}

Gyűjtemények

String url = "mongodb://root:titok@localhost:27017";
 
ConnectionString cs = new ConnectionString(url);
MongoClient client = MongoClients.create(cs);
MongoDatabase database = client.getDatabase("zoldzrt");
database.listCollectionNames().forEach(System.out::println);

Teljes kód:

App.java

import com.mongodb.ConnectionString;
import com.mongodb.MongoException;
import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
import com.mongodb.client.MongoDatabase;
 
public class App {
    public static void main(String[] args) throws Exception {
        try {
            String url = "mongodb://root:titok@localhost:27017";
 
            ConnectionString cs = new ConnectionString(url);
            MongoClient client = MongoClients.create(cs);
            MongoDatabase database = client.getDatabase("zoldzrt");
            database.listCollectionNames().forEach(System.out::println);
 
        } catch (MongoException e) {
            System.err.println("Hiba! A kapcsolódás sikertelen!");
            System.err.println(e.getMessage());
        }
 
    }
}

Beszúrás

Document doc = new Document();
doc.put("name", "Erős István");
doc.put("city", "Szeged");
doc.put("salary", 395.2);
collection.insertOne(doc);

Teljes kód:

App.java

import org.bson.Document;
import com.mongodb.ConnectionString;
import com.mongodb.MongoException;
import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
 
public class App {
    public static void main(String[] args) throws Exception {
        try {
            String url = "mongodb://root:titok@localhost:27017";
 
            ConnectionString cs = new ConnectionString(url);
            MongoClient client = MongoClients.create(cs);
            MongoDatabase database = client.getDatabase("zoldzrt");
            MongoCollection<Document> collection = database.getCollection("employees");
 
            Document doc = new Document();
            doc.put("name", "Lime Lajos");
            doc.put("city", "Pécs");
            doc.put("salary", 392.8);
            collection.insertOne(doc);
 
        } catch (MongoException e) {
            System.err.println("Hiba! A kapcsolódás sikertelen!");
            System.err.println(e.getMessage());
        }
 
    }
}

Első

import org.bson.Document;
 
import com.mongodb.ConnectionString;
import com.mongodb.MongoException;
import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
 
public class App {
    public static void main(String[] args) throws Exception {
        try {
            String url = "mongodb://root:titok@localhost:27017";
 
            ConnectionString cs = new ConnectionString(url);
            MongoClient client = MongoClients.create(cs);
            MongoDatabase database = client.getDatabase("zoldzrt");
            MongoCollection<Document> collection = database.getCollection("employees");
 
            Document document = collection.find().first();
            System.out.println(document.get("name"));
        } catch (MongoException e) {
            System.err.println("Hiba! A kapcsolódás sikertelen!");
            System.err.println(e.getMessage());
        }
 
    }
}

Program

App.java

import org.bson.Document;
 
import com.mongodb.ConnectionString;
import com.mongodb.MongoException;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
 
public class App {
    public static void main(String[] args) throws Exception {
        try {            
 
            String url = "mongodb://root:titok@localhost:27017";
 
            ConnectionString cs = new ConnectionString(url);
            MongoClient client = MongoClients.create(cs);
            MongoDatabase database = client.getDatabase("zoldzrt");
            MongoCollection<Document> collection = database.getCollection("employees");
 
            FindIterable<Document> docs = collection.find();
            docs.forEach(doc -> System.out.println(doc));
        } catch (MongoException e) {
            System.err.println("Hiba! A kapcsolódás sikertelen!);
            System.err.println(e.getMessage());
            System.err.println(e);            
        }
 
    }
}

Link

https://www.baeldung.com/java-mongodb (2024)