NoClassDefFoundError in WebLogic 8

[Simeon Cherniy]

Hello.
I've the following problem and I can't understand it.

The static method of my class (A) was called from the business method of the session bean (CMT).

Firstly, my class was like:

    
public class A {
 
    private static A a = new A();
 
    public static A getInstance()
    {
        return a;
    }
 
//methods
...
}

In the session bean I call the method of this class:

A.getInstance().methodName();

Here I had the NoClassDefFoundError (from log-file).

After I had replased the code:

    
public class A {
 
    private static A a;
 
    public static A getInstance()
    {
        if(a == null)
        {
            a = new A();
        }
        return a;
    }
...
}

It works fine.

But I don't understand the reason of the first error.