Why was this exception not caught?

The error that you saw in a runtime error thrown for a class that was expected to be in the CLASSPATH but was not found. If jdom. Jar does indeed include org/jaxen/NamespaceContext class then that should fix this issue.

I had forgotten to include a library that was a dependency of the jdom. Jar library. When I run the application I saw this error.

The error that you saw in a runtime error thrown for a class that was expected to be in the CLASSPATH but was not found. If jdom. Jar does indeed include org/jaxen/NamespaceContext class then that should fix this issue.

According to the JDOM documentation, the newInsance() method throws a JDOMEXCeption so shouldnt it have caught the error? No this is not a JDOMException, it's a NoClassDefFoundError, therefore it does not catch it. Most importantly, this happens before JDOM class is in the picture - happens during class loading.

Also, how can I avoid having to add a catch(Exception e) clause to avoid unknown exceptions In general you should not try to catch NoClassDefFoundError since it is a type of error that falls under the category of failures from which recovery is not feasible. You can try to work around it by using Reflection and catching ClassNotFoundException but as I said in general this is an exception you cannot recover from so attempts to catch it is probably a moot point.

This exception is not raised by the constructor. It's raised by the class loader. When it tries to load your class long before the constructor runs, the class was not found and this exception (No Class Defination Found Error) was raised which you have not handled (BTW errors can't be handled).

It is common to create a specific classloader to be able to handle class loader errors. – Thorbjørn Ravn Andersen Apr 30 at 16:07 1 huh? Whether you use the default classloader or a custom one, they won't work if you don't actually specify all the jars needed on the classpath.

– MeBigFatGuy Apr 30 at 17:25.

It wasn't caught because it wasn't thrown. The exception thrown was a java.lang. NoClassDefFoundError And if you want to catch an Exception, you have to catch it.

There is nothing you can do to avoid this, that would kind of defeat the whole point of exceptions.

– ziggy Apr 30 at 15:58 No on two counts.1) The catch will only catch exceptions of type JDOMException and any subclasses. NoClassDefFoundError is not a sub-class of JDOMException. 2) The exception isn't been thrown here anyway, it's been thrown by the classloader.

– Richard H Apr 30 at 15:59 NoClassDefFoundError doesn't extend "Exception". But even if it did, it wouldn't have been caught in a catch JDOMException clause. It wouldn't be caught in a catch Exception clause either... – Don Roby Apr 30 at 15:59.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.

Related Questions