What is the value of i when you execute the code below and why?
int i = (Integer)null;
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Gustavo
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I already did. It's the why that interests me most, an may be useful to other people. – Gustavo Dec 18 '18 at 15:21
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1@Gustavo "why" is "because it was designed like that", and it's documented in the relevant JLS. – BackSlash Dec 18 '18 at 15:22
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Ok. But comments is not the right place to answer. – Gustavo Dec 18 '18 at 15:22
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Null gets correctly cast to an Integer. Java attempts to unbox the integer into a primitive int so that it may store it in the variable, effectively calling `null.intValue()` which results in a NPE. – Michael Dec 18 '18 at 15:28
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Guys, the section below is the right place to answer, not here. Also, this is not a duplicate, because it's not about casting, but about unboxing. – Gustavo Dec 18 '18 at 15:32
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1Duplicate of https://stackoverflow.com/questions/2382058/unboxing-null-object-to-primitive-type-results-in-nullpointerexception-fine , should probably be updated – BackSlash Dec 18 '18 at 15:36
