Check if last getter in method chain is not null

Question

In code we have got a lot of chain methods, for example obj.getA().getB().getC().getD(). I want to create helper class which will check if method getD()

Answer 1

As already stated, the true solution is refactoring.

In the meantime, you could just wrap your first workaround in a function:

static D getD(MyClass obj) {

    try {
        return obj.getA().getB().getC().getD();
    }
    catch (NullPointerException e) {
        return null; // Or even better, some default D
    }
}

At the caller site:

D d = getD(obj);

At least you don't have to trash the caller with try-catch blocks. You still need to handle the errors somehow, when some of the intermediate getX() call returns a null and so d becomes null. The best would be to return some default D in the wrapper function.

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I don't see how the two options you list at the end of your question would help if any of the intermediate getX() returns a null; you will get a NullPointerException.