application connects to Oracle but executable jar can't

[cadoltt]

Hi everybody!

I need to clarify something. I've created a simple application which connects to an Oracle db and executes a simple Select query. I work with Eclipse and when I run the app from within Eclipse, or I start it from the command prompt window, it goes all right but when I try to run an executable jar, connection fails and I am getting an error message: 'java.lang.ClassNotFoundException: oracle.jdbc.OracleDriver'.

The oracle driver is added to my CLASSPATH variable. Is there anything I have to add to the jar?

Can anyone help?

Thanks,
Alex

 

[sedj]

The driver class is called :

oracle.jdbc.driver.OracleDriver

not :

oracle.jdbc.OracleDriver

--------------------------------------------------
Free Java/J2EE Database Connection Pooling Software

http://www.primrose.org.uk

 

[cadoltt]

Hi sedj,

Thanks for your response. I changed the class name but it didn't help - now I'm getting this message:
'java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver'

Should it be anything specific in the Manifest file?

Thanks again,
Alex

 

[sedj]

You do have classes12.jar in the CLASSPATH ?

--------------------------------------------------
Free Java/J2EE Database Connection Pooling Software

http://www.primrose.org.uk

 

[cadoltt]

sedj,

I use ojdbc14_g.jar and it is set in the CLASSPATH...

Alex

 

[sedj]

Never used ojdbc14_g.jar - try using classes12.jar, or at least adding it to your CLASSPATH - this is where the class you are missing lives.

--------------------------------------------------
Free Java/J2EE Database Connection Pooling Software

http://www.primrose.org.uk

 

[cadoltt]

sedj,

Thank you for your help.

I downloaded classes12.zip added it to the CLASSPATH, rebuit the app but still having the same problem with the same error message.

Is it essential that I installed classes12.zip, not classes12.jar?

Alex

 

[sedj]

I've seen odd things happen when you add classes12.zip - rename the file classes12.jar .

If you still have problems, then I can pretty much assure you classes12.jar is not on your CLASSPATH.

--------------------------------------------------
Free Java/J2EE Database Connection Pooling Software

http://www.primrose.org.uk

 

[cadoltt]

sedj,

I did what you suggested, and checked my CLASSPATH (I actually corrected the file extension in there as well). Doesn't work....


Alex

 

[Diancecht]

Did you try with an explicit java -classpath?

Cheers,
Dian

 

[sedj]

Try this programme in a DOS or Linux console :

public class TestDriverClass {
  public static void main(String[] args) {
    Class.forName("oracle.jdbc.driver.OracleDriver");
  }
}

Compile it, and then run it like this :

First, set your classpath by hand,

On Linux :
export CLASSPATH=.:/path/to/classes12.jar

or on Win32 :

set CLASSPATH=.;C:\path\to\classes12.jar

and then run it :

java TestDriverClass

What happens ?

--------------------------------------------------
Free Java/J2EE Database Connection Pooling Software

http://www.primrose.org.uk

 

[cadoltt]

Diancecht,

Thanks for joining.

I cant compile it it gives me the following error message:

TestDriverClass.java:5: unreported exception java.lang.ClassNotFoundException; must be caught or declared to be thrown Class.forName("oracle.jdbc.driver.OracleDriver");

What's wrong?

Alex

 

[Diancecht]

Just a try-catch block

public class TestDriverClass {
  public static void main(String[] args) {
   try {
    Class.forName("oracle.jdbc.driver.OracleDriver");
   } catch (Exception e) {
    e.printstacktrace();
   }
  }
}

Cheers,
Dian

 

[cadoltt]

Diancecht,

I embraced the code into try/catch block and it compiled.

When I ran it, nothing happened, after a little while it came to the usual system prompt (I work in win 2000).

....Alex

 

[Diancecht]

Did you include any message in the catch block?

Cheers,
Dian

 

[stefanwagner]

If you run a program from an jar, the classpath has to be specified in the manifest:

Class-Path: xyz.jar

The classpath-variable is ignored afaik.

sedj: I thought classes12.jar where introduced for java-1.2, and used oracle10g recently, which introduced a different jar, but it's on a different machine now, so I can't verify the name, but I surely didn't need a 'classes12.jar'.

seeking a job as java-programmer in Berlin:

http://home.arcor.de/hirnstrom/bewerbung

 

[cadoltt]

Dian,

yes, I included messages in the try-catch block:

try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("all OK");
}
catch (Exception e)
{
System.out.println("Err=" + e);
}

I also tried this

try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("all OK");
}
catch(ClassNotFoundException e)
{
System.out.println("Err=" + e);
}


In both cases when it runs, comes the message "all OK".



stefanwagner,

Thank you too for joining the club

I included the line into my manifest file. Here it is:

Manifest-Version: 1.0
Main-Class: clsMain
Class-Path: C:\j2sdk1.4.2_03\oracle_driver\classes12.jar


But now I am getting another strange message when I try to run the jar file:

'Could not find the main class. Program will exit'


I looked into the jar, my clsMain (which contains the main function) is in there...

Alex

 

[Diancecht]

Follow the leader:

http://java.sun.com/docs/books/tutorial/jar/manifest/index.html

Cheers,
Dian

 

[sedj]

Right - so what this all means then, is that the driver IS FOUND in your manual classpath - and your other programme does not have the classpath defined- so as I said before- its a CLASSPATH issue which you need to resolve.

--------------------------------------------------
Free Java/J2EE Database Connection Pooling Software

http://www.primrose.org.uk

 

[cadoltt]

sedj,

Here is my entire CLASSPATH var:

C:\Program Files\Java\jre1.5.0_04\lib\ext\QTJava.zip;C:\j2sdk1.4.2_03\oracle_driver\ojdbc14_g.jar;C:\j2sdk1.4.2_03\oracle_driver\classes12.jar;


Anything wrong with it?

Thanks,
Alex