ClassNotFoundException

[Punya Pratap Singh]

Class.forName("net.sourceforge.jtds.jdbc.Driver");//this line throws Exception
Connection connection = DriverManager.getConnection(
"jdbc:microsoft:sqlserver://localhost:1433/tempdb", "", "");

I am new in jdbc.

Code is -


I first downloaded the Jtds.jar and set class path in cmd as--

set classpath = C:\Program Files\SQL server driver\jtds-1.2.5.jar

Also I am using windows authentication.and unable to set Sql server authentication.

It is still throwing Exception please guide me.

Exception in thread "main" java.lang.ClassNotFoundException: net.sourceforge.jtds.jdbc.Driver
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Unknown Source)
	at Test.<init>(Test.java:9)
	at Test.main(Test.java:31)

[Campbell Ritchie]

Ask your computer to echo your classpath. Because there are spaces in it, you may need to surround the classpath in "quotes".

[Philip Grove]

Campbell Ritchie wrote:Ask your computer to echo your classpath. Because there are spaces in it, you may need to surround the classpath in "quotes".

While normally a good theory, the environment variables on my Windows computer (including the classpath) contain spaces and works fine. If you set an environment variable in Windows my experience is that the change does not take effect on the command line before you start a new session.

[Paul Clapham]

Philip Grove wrote:... the environment variables on my Windows computer (including the classpath) contain spaces and works fine...

That may be true, but that would be because you set it up correctly. The line posted by Punya doesn't do that. It needs quotes.

[Punya Pratap Singh]

Thanks for your replies.
As suggested I used quotes this time in setting Class Path,but result is still the same.
Also when I do-

echo %CLASSPATH%
results is - %CLASSPATH%
but is not showing any classpath which has been set.

[Ashutosh Limaye]

to display classpath the command is

set classpath

without the assignment operator.

[Punya Pratap Singh]

When I use the command then output is as follows ---

C:\>set classpath

CLASSPATH=C:\Program Files\SQL server driver\jtds-1.2.5.jar;

Also I have a question that classpath also been set for java.then why only class path for this particular jar is showing,why not for all set class path's.

Also suggest me ,where am I doing wrong in previous problem.(Connecting to Database).

[Vijitha Kumara]

Also I have a question that classpath also been set for java...

Looking at the out put of CLASSPATH it doesn't. You don't need to set it for Java core libraries.

where am I doing wrong in previous problem.(Connecting to Database).

How you run the program?

[Punya Pratap Singh]

The Code I am using is---

public class Test {
	public Test() throws Exception {
		// Get connection
		// DriverManager.registerDriver(net.sourceforge.jtds.jdbc.Driver);
		Class.forName("net.sourceforge.jtds.jdbc.Driver");

		Connection connection = DriverManager.getConnection(
				"jdbc:microsoft:sqlserver://localhost:1433/tempdb", "", "");
		if (connection != null) {
			System.out.println();
			System.out.println("Successfully connected");
			System.out.println();
			// Meta data
			DatabaseMetaData meta = connection.getMetaData();
			System.out.println("\nDriver Information");
			System.out.println("Driver Name: " + meta.getDriverName());
			System.out.println("Driver Version: " + meta.getDriverVersion());
			System.out.println("\nDatabase Information ");
			System.out.println("Database Name: "
					+ meta.getDatabaseProductName());
			System.out.println("Database Version: "
					+ meta.getDatabaseProductVersion());
		}
	} // Test

	public static void main(String args[]) throws Exception {
		Test test = new Test();
	}
}

[Ashutosh Limaye]

Punya Pratap Singh wrote:When I use the command then output is as follows ---

C:\>set classpath

CLASSPATH=C:\Program Files\SQL server driver\jtds-1.2.5.jar;

Also I have a question that classpath also been set for java.then why only class path for this particular jar is showing,why not for all set class path's.

Also suggest me ,where am I doing wrong in previous problem.(Connecting to Database).

Try setting it again as:

set classpath = "C:\Program Files\SQL server driver\jtds-1.2.5.jar";%classpath%

And then check the classpath again.

[Ulf Dittmer]

IMO, using the CLASSPATH environment variables is more trouble than it's worth. Something like this would be preferable:

java -cp "C:\Program Files\SQL server driver\jtds-1.2.5.jar;." Test

[Ashutosh Limaye]

Ulf Dittmer wrote:IMO, using the CLASSPATH environment variables is more trouble than it's worth. Something like this would be preferable:

java -cp "C:\Program Files\SQL server driver\jtds-1.2.5.jar;." Test

Yep That's a better approach. That will ensure it takes the right path to the jar.

[Punya Pratap Singh]

Thanks Ulf Dittmer,Ashutosh

Now It is able to locate the class but saying that this driver is not appropriate.
As I already mentioned that I am using windows autentication.
Is it not possible to connect to Sql server with windows autentication ??

C:\WebApplications\TestingJava\bin>java -cp "C:\Program Files\SQL server driver\
jtds-1.2.5.jar;." Test
Exception in thread "main" java.sql.SQLException: No suitable driver found for j
dbc:microsoft:sqlserver://localhost:1433/tempdb
        at java.sql.DriverManager.getConnection(Unknown Source)
        at java.sql.DriverManager.getConnection(Unknown Source)
        at Test.<init>(Test.java:11)
        at Test.main(Test.java:31)

[Rob Sang]

Punya Pratap Singh wrote:Thanks Ulf Dittmer,Ashutosh

Now It is able to locate the class but saying that this driver is not appropriate.
As I already mentioned that I am using windows autentication.
Is it not possible to connect to Sql server with windows autentication ??

C:\WebApplications\TestingJava\bin>java -cp "C:\Program Files\SQL server driver\
jtds-1.2.5.jar;." Test
Exception in thread "main" java.sql.SQLException: No suitable driver found for j
dbc:microsoft:sqlserver://localhost:1433/tempdb
        at java.sql.DriverManager.getConnection(Unknown Source)
        at java.sql.DriverManager.getConnection(Unknown Source)
        at Test.<init>(Test.java:11)
        at Test.main(Test.java:31)

The URL you've used indicates the Microsoft proprietary SQLServer JDBC driver. To use JTDS you need

jdbc:jtds://localhost:1433/tempdb

[Vijitha Kumara]

Welcome to CodeRanch, Rob Sang!

[Rob Sang]

Vijitha Kumara wrote:Welcome to CodeRanch, Rob Sang!

Thank you

[Punya Pratap Singh]

Hi,

Now when I try to connect with following connection string it throws following Error.And I am using windows authentication.

Class.forName("net.sourceforge.jtds.jdbc.Driver");

		Connection connection = DriverManager
				.getConnection("jdbc:jtds:microsoft//localhost:1433/tempdb"); 

C:\WebApplications\TestingJava\bin>java -cp "C:\Program Files\SQL server driver\
jtds-1.2.5.jar;." Test
Exception in thread "main" java.sql.SQLException: The syntax of the connection U
RL 'jdbc:jtds:microsoft//localhost:1433/tempdb' is invalid.
        at net.sourceforge.jtds.jdbc.Driver.setupConnectProperties(Driver.java:2
45)
        at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:181)
        at java.sql.DriverManager.getConnection(Unknown Source)
        at java.sql.DriverManager.getConnection(Unknown Source)
        at Test.<init>(Test.java:11)
        at Test.main(Test.java:31)

[Philip Grove]

Use the connect string that Rob posted, that should clear up your problems. One good thing though, it is the driver that is complaining so there is no problems finding the correct driver.

[Punya Pratap Singh]

Now It is giving following Exception ,What could be the possible causes,
Please Help me.

Exception in thread "main" java.sql.SQLException: Network error IOException: Con
nection refused: connect
        at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java
:410)
        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 Test.<init>(Test.java:11)
        at Test.main(Test.java:31)
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(SharedSoc
ket.java:307)
        at net.sourceforge.jtds.jdbc.SharedSocket.<init>(SharedSocket.java:257)
        at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java
:311)
        ... 6 more

[Philip Grove]

Start a new thread to avoid getting overlooked as it is a different problem and different exception, and this time please post your code as we can't help without seeing the code.

Generally a connection refused is not a code issue, of course it can be. It is far more likely to be caused by the server no longer running in the same place or even allowing connections from the place of your code.

[Punya Pratap Singh]

The code is same as above.that is why I posted it here.

[Philip Grove]

The code might be the same, but the problem and the exception is another and this thread is titled "ClassNotFoundException".

Verify that you can connect to the server through other means than your code, from the same computer that your code runs on.

[Deepthi Tanguturi]

Philip Grove wrote:The code might be the same, but the problem and the exception is another and this thread is titled "ClassNotFoundException".

Verify that you can connect to the server through other means than your code, from the same computer that your code runs on.

I think,jar file was not set tot the classpath.When you can't set jar file to the classpath.This problem comes.Please check classpath by using echo command.