Connection SQL server 2012 - Eclipse Neon

Question

I'm working on a project in which I need to conenct the Eclipse IDE to an SQLServer database. I downloaded and imported the .jar SQLJBDC driver file in Eclipse, and put the following code in my class:

`import java.sql.*;
import java.sql.DriverManager;

public class connexion {

// Méthode permettant d'enregistrer des données dans la base de données
public static void rempli() {

    String url = "jdbc:sqlserver://localhost:1433;databaseName=Tunnel" ;// le chemin vers le serveur de BD et la base de données
    String user = "sa"; // Nom d'un utilisateur de la base de données
    String pass = "*********"; // Son mot de passe
    Connection cn = null; // Déclaration d'un objet de type connection, il permet d'utiliser une méthode de connexion
    Statement st = null; // Déclaration d'un objet Statement. il permet d'envoyer des requêtes
    try {

                //Etape 1 : Chargement du driver
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
                //Etape 2 : récupération de la connexion
            cn = DriverManager.getConnection(url, user, pass);


    }
    catch (SQLException | ClassNotFoundException e) {

        e.printStackTrace();
    }
}
public static void main(String[] args) {

    rempli();
}
}`

When I launched the program, I had the following answer after nearly 20 seconds:

com.microsoft.sqlserver.jdbc.SQLServerException: Échec de la connexion TCP/IP à l'hôte localhost, port 1433. Erreur : « Connection refused: connect. Vérifiez les propriétés de connexion. Assurez-vous qu'une instance de SQL Server est en cours d'exécution sur l'hôte et accepte les connexions TCP/IP au port. Vérifiez que les connexions TCP au port ne sont pas bloquées par un pare-feu. ».
at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDriverError(SQLServerException.java:191)
at com.microsoft.sqlserver.jdbc.SQLServerException.ConvertConnectExceptionToSQLServerException(SQLServerException.java:242)
at com.microsoft.sqlserver.jdbc.SocketFinder.findSocket(IOBuffer.java:2369)
at com.microsoft.sqlserver.jdbc.TDSChannel.open(IOBuffer.java:551)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:1963)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:1628)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectInternal(SQLServerConnection.java:1459)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:773)
at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:1168)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at connexion.rempli(connexion.java:21)
at connexion.main(connexion.java:32)

I deactivated my firewall, authorized access on the different ports TPC and I don't really know what to do more now. Can anyone help me?

Thank you for the help!

Answer 1

If you have already configured your MS SQL server to listen on TCP/IP traffic, then it could be any of these reasons:

• Firewall is blocking the incoming connection
• SQL SERVER is not running on the host
• The port you have configured is not correct, ie its not 1433

If you've validated that the issue doesn't fall into the above categories, then you may try doing this to enable port 1433 for TCP/IP traffic!

• Go to Start -> All Programs -> Microsoft SQL Server 2008/2012/2014 -> Configuration Tools
• Click SQL Server Configuration Manager
• Expand SQL Server Network Configuration-> Protocol
• Enable TCP/IP Right box
• Double Click on TCP/IP and go to IP Addresses Tab and add 1433 under TCP port.

After these changes, you will have to restart your SQL Server Services > SQL Server

If these are not helping then you may consider adding the following as well:

System.setProperty("java.net.preferIPv4Stack", "true");

Or to pass it as a VM option: -Djava.net.preferIPv4Stack=true

Hope this helps!