java ClassNotFoundException for org.h2.Driver

Question

I am trying to use H2 to connect to a database in Java (using Eclipse as the IDE). The sample does (below) throws a ClassNotFoundException. The thing is, I did add the h2 jar file to the system CLASSPATH. I have even checked it's there several times via 'printenv' in the console. Am I omitting a step?

CODE:

import java.sql.*;

public class Program {

 /**
  * @param args
  */
 public static void main(String[] args) 
  throws Exception{

  try{
   System.out.println("hello, world!");
   Class.forName("org.h2.Driver");
   Connection conn = DriverManager.getConnection("jdbc:h2:~/testdb", "sa", "");
   // add application code here
   conn.close();
  }catch(ClassNotFoundException ex){
   System.out.println( "ERROR: Class not found: " + ex.getMessage() );

  }
  System.exit(0);

 }

}

Answer 1

The sample does (below) throws a ClassNotFoundException

Then the driver is not on the classpath.

The thing is, I did add the h2 jar file to the system CLASSPATH. I have even checked it's there several times via 'printenv' in the console.

How did you do that exactly? Please show the obtained output.

Am I omitting a step?

I can't say with the provided informations. But relying on the CLASSPATH environment variable is a bad practice anyway and you should use the -cp option if you're running Java on the command line. Like this:

java -cp h2.jar com.acme.Program

---

Is there a way I can set Eclipse to use the jar file when I use the RUN menu so that I don't have to run from the Console all the time?

Yes. Under Eclipse, add the JAR to the project build path: right-click on your project then Properties > Java Build Path > Libaries > Add JARS... (assuming the H2 JAR is available in a directory relative to your project). Others IDE have equivalent way of doing this.