JDK-14 Exception Details Feature : Add More Details To Your NullPointerException

Java Mohamed BELMAHI May 29, 2020 224 < 1 min

JDK-14 provides a new ability to developer for checking root cause of a NullPointerException.

So instead of getting only code line number as a root cause of your NullPointerException, like :

Old NullPointerException

public static void main(String[] args) {
        String mystring = null;

        System.out.println(mystring.toString());
    }


Exception in thread "main" java.lang.NullPointerException
	at YourClass.main(your_class.java:5)

From JDK-14 You are can get more details about a NullPointerException by adding the following argument on VM Options :

New VM Argument for more exception details

-XX:+ShowCodeDetailsInExceptionMessages

Result after applying this change :

After adding new ShowCodeDetailsInExceptionMessages argument

public static void main(String[] args) {
        String mystring = null;

        System.out.println(mystring.toString());
    }


Exception in thread "main" java.lang.NullPointerException: Cannot invoke "String.toString()" because "mystring" is null
	at YourClass.main(your_class.java:5)

Mohamed BELMAHI

Java/JavaEE (Hybris/Spring) & Full Stack Senior Developer

I’m passionate about new technologies or any kind of thing that change our lifestyle to better either by automatisation of existing process or creating new solution.

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