JVM vs Programmatically Exception

[Adolfo Eloy]

Hi all.

I'm studying about exceptions, and I have a doubt when forcing some situation to throw ExceptionInInitializerError
using a NullPointerException.

Looking the code that follows, I'd like to know, if throwing an ExceptionInInitializeErro (JVM exception) must be
considered a programmatically exception because of the NullPointerException that causes it.

If a question like this appears on the exam, could I answer with JVM Exception even the cause being a programmatically exception?

public class ErrorInitializing {

	static int a = getValue();
	static Integer getValue() { 
		return null;  
	}
	
	public static void main(String[] args) {
		System.out.println("test:" + a);
	}
}

java.lang.ExceptionInInitializerError
Caused by: java.lang.NullPointerException
at exceptions.ErroInicializacao.<clinit>(ErroInicializacao.java:5)
Exception in thread "main"


Tks!

[Matthew Brown]

It's not a programmatic exception because nowhere has a programmer written throw new ExceptionInInitializerError(). The question is whether the programmer controls the creation of the exception/error, not whether they caused it due to a mistake.

Similarly, NullPointerException is also thrown by the JVM.

[Adolfo Eloy]

Sorry,
I was wrong when I said that NullPointerException was thrown programmatically.

The question is whether the programmer controls the creation of the exception/error, not whether they caused it due to a mistake.

So, if I throw my onwn created exception programmatically inside an initialization block getting an ExceptionInInitializerError,
caused by MyException, could I consider it as thrown programmatically?

Example:

class MyException extends RuntimeException {} 

public class ErroInicializacao {

	static int a = getValueException(); 
	static int getValueException() {
		// throwing programmatically
		throw new MyException();
	}
	
	public static void main(String[] args) {
		System.out.println("test:" + a);
	}
}

Output:
java.lang.ExceptionInInitializerError
Caused by: exceptions.MyException
at exceptions.ErroInicializacao.getValueException(ErroInicializacao.java:10)
at exceptions.ErroInicializacao.<clinit>(ErroInicializacao.java:7)
Exception in thread "main"

Thanks

[Matthew Brown]

In that case the MyException is thrown programmatically. The ExceptionInInitializerError is thrown by the JVM in response to an uncaught error occurring during initialisation.

[Adolfo Eloy]

Thank you Matthew.

I understand now.