Create a jTDS connection string

问题

my sql server instance name is MYPC\SQLEXPRESS and I'm trying to create a jTDS connection string to connect to the database 'Blog'. Can anyone please help me accomplish that?

I'm trying to do like this:

DriverManager.getConnection("jdbc:jtds:sqlserver://127.0.0.1:1433/Blog", "user", "password");

and I get this:

 java.sql.SQLException: Network error IOException: Connection refused: connect
    at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:395)
    at net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:50)
    at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:184)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at SqlConnection.Connect(SqlConnection.java:19)
    at main.main(main.java:11)
Caused by: java.net.ConnectException: Connection refused: connect
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.PlainSocketImpl.doConnect(Unknown Source)
    at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at net.sourceforge.jtds.jdbc.SharedSocket.createSocketForJDBC3(SharedSocket.java:305)
    at net.sourceforge.jtds.jdbc.SharedSocket.<init>(SharedSocket.java:255)
    at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:323)
    ... 6 more

回答1:

As detailed in the jTDS Frequenlty Asked Questions, the URL format for jTDS is:

jdbc:jtds:<server_type>://<server>[:<port>][/<database>][;<property>=<value>[;...]]

So, to connect to a database called "Blog" hosted by a MS SQL Server running on MYPC, you may end up with something like this:

jdbc:jtds:sqlserver://MYPC:1433/Blog;instance=SQLEXPRESS;user=sa;password=s3cr3t

Or, if you prefer to use getConnection(url, "sa", "s3cr3t"):

jdbc:jtds:sqlserver://MYPC:1433/Blog;instance=SQLEXPRESS

EDIT: Regarding your Connection refused error, double check that you're running SQL Server on port 1433, that the service is running and that you don't have a firewall blocking incoming connections.

回答2:

Really, really, really check if the TCP/IP protocol is enabled in your local SQLEXPRESS instance.

Follow these steps to make sure:

Open "Sql Server Configuration Manager" in "Start Menu\Programs\Microsoft SQL Server 2012\Configuration Tools\"
Expand "SQL Server Network Configuration"
Go in "Protocols for SQLEXPRESS"
Enable TCP/IP

If you have any problem, check this blog post for details, as it contains screenshots and much more info.

Also check if the "SQL Server Browser" windows service is activated and running:

Go to Control Panel -> Administrative Tools -> Services
Open "SQL Server Browser" service and enable it (make it manual or automatic, depends on your needs)
Start it.

That's it.

After I installed a fresh local SQLExpress, all I had to do was to enable TCP/IP and start the SQL Server Browser service.

Below a code I use to test the SQLEXPRESS local connection. Of course, you should change the IP, DatabaseName and user/password as needed.:

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;

public class JtdsSqlExpressInstanceConnect {
    public static void main(String[] args) throws SQLException {
        Connection conn = null;
        ResultSet rs = null;
        String url = "jdbc:jtds:sqlserver://127.0.0.1;instance=SQLEXPRESS;DatabaseName=master";
        String driver = "net.sourceforge.jtds.jdbc.Driver";
        String userName = "user";
        String password = "password";
        try {
            Class.forName(driver);
            conn = DriverManager.getConnection(url, userName, password);
            System.out.println("Connected to the database!!! Getting table list...");
            DatabaseMetaData dbm = conn.getMetaData();
            rs = dbm.getTables(null, null, "%", new String[] { "TABLE" });
            while (rs.next()) { System.out.println(rs.getString("TABLE_NAME")); }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            conn.close();
            rs.close();
        }
    }
}

And if you use Maven, add this to your pom.xml:

<dependency>
    <groupId>net.sourceforge.jtds</groupId>
    <artifactId>jtds</artifactId>
    <version>1.2.4</version>
</dependency>

回答3:

jdbc:jtds:sqlserver://x.x.x.x/database replacing x.x.x.x with the IP or hostname of your SQL Server machine.

jdbc:jtds:sqlserver://MYPC/Blog;instance=SQLEXPRESS

jdbc:jtds:sqlserver://MYPC:1433/Blog;instance=SQLEXPRESS

If you are wanting to set the username and password in the connection string too instead of against a connection object separately:

jdbc:jtds:sqlserver://MYPC/Blog;instance=SQLEXPRESS;user=foo;password=bar

(Updated my incorrect information and add reference to the instance syntax)

回答4:

A shot in the dark, but From the looks of your error message, it seems that either the sqlserver instance is not running on port 1433 or something is blocking the requests to that port

回答5:

SQLServer runs the default instance over port 1433. If you specify the port as port 1433, SQLServer will only look for the default instance. The name of the default instance was created at setup and usually is SQLEXPRESSxxx_xx_ENU.

The instance name also matches the folder name created in Program Files -> Microsoft SQL Server. So if you look there and see one folder named SQLEXPRESSxxx_xx_ENU it is the default instance.

Folders named MSSQL12.myInstanceName (for SQLServer 2012) are named instances in SQL Server and are not accessed via port 1433.

So if your program is accessing a default instance in the database, specify port 1433, and you may not need to specify the instance name.

If your program is accessing a named instance (not the default instance) in the database DO NOT specify the port but you must specify the instance name.

I hope this clarifies some of the confusion emanating from the errors above.

来源：https://stackoverflow.com/questions/1862283/create-a-jtds-connection-string

标签

java

jdbc

connection-string

jtds