exception in initializer error in java when using Netbeans
@Christian Ullenboom' explanation is correct.
I'm surmising that the OBD2nerForm
code you posted is a static initializer block and that it is all generated. Based on that and on the stack trace, it seems likely that generated code is tripping up because it has found some component of your form that doesn't have the type that it is expecting.
I'd do the following to try and diagnose this:
- Google for reports of similar problems with NetBeans generated forms.
- If you are running an old version of NetBeans, scan through the "bugs fixed" pages for more recent releases. Or just upgrade try a newer release anyway to see if that fixes the problem.
- Try cutting bits out of the form design until the problem "goes away" ... and try to figure out what the real cause is that way.
- Run the application under a debugger to figure out what is being (incorrectly) type cast as what. Just knowing the class names may help. And looking at the instance variables of the objects may reveal more; e.g. which specific form component is causing the problem.
My suspicion is that the root cause is a combination of something a bit unusual (or incorrect) with your form design, and bugs in the NetBeans form generator that is not coping with your form. If you can figure it out, a workaround may reveal itself.
You get an ExceptionInInitializerError if something goes wrong in the static initializer block.
class C
{
static
{
// if something does wrong -> ExceptionInInitializerError
}
}
Because static variables are initialized in static blocks there are a source of these errors too. An example:
class C
{
static int v = D.foo();
}
=>
class C
{
static int v;
static
{
v = D.foo();
}
}
So if foo() goes wild, you get a ExceptionInInitializerError.
Hope this helps...
class SomeClass{
//Code snippet here...
}
Code snippet 1: Absolutely OK - all checked exceptions handled
static void m1(){
try{
throw new Exception();
} catch(Exception e){
System.out.println(e);
}
}
static{
m1();
}
Code snippet 2: Won't compile - unreported checked exception
static void m1() throws Exception{
throw new Exception();
}
static{
m1();
}
Code snippet 3: OK (see code snippet 1)
static void m1() throws Exception{
throw new Exception();
}
static{
try{m1();}
catch(Exception e){
System.out.println(e);
//or whatever
}
}
Code snippet 4: Compilation error, initilalizer must be able to complete normally
static{
throw new RuntimeException();
}
Basically it boils down to this:
- Inside the static block, every checked exception MUST have a handler.
- If a RuntimeException were to occur, it would be wrapped in ExceptionInInitializerError and then the latter would be thrown.
This makes sense as A CLASS SHOULD BE ABLE TO COMPLETE INITIALIZATION NORMALLY. If this happens to be a problem, this should be categorized as an Error (from which recovery is usually difficult or impossible) rather than an Exception (which is usually recoverable)...