NPE(NullPointException)

 

 

 

NPE(NullPointException)

·       Tony Hoare(토니 호어)가 실수로 null 참조를 1965년에 처음 고안한 것으로 알려져 있습니다.

·       현재 null참조로 인해 다양한 언어에서 문제가 발생하기도 합니다.

 

Apologies and retractions Speaking at a software conference called QCon London in 2009, he apologised for inventing the null reference:[23]   I call it my billion-dollar mistake. It was the invention of the null reference in 1965. At that time, I was designing the first comprehensive type system for references in an object oriented language (ALGOL W). My goal was to ensure that all use of references should be absolutely safe, with checking performed automatically by the compiler. But I couldn't resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years.     For many years under his leadership his Oxford department worked on formal specification languages such as CSP and Z. These did not achieve the expected take-up by industry, and in 1995 Hoare was led to reflect upon the original assumptions:[24]   Ten years ago, researchers into formal methods (and I was the most mistaken among them) predicted that the programming world would embrace with gratitude every assistance promised by formalisation to solve the problems of reliability that arise when programs get large and more safety-critical. Programs have now got very large and very critical – well beyond the scale which can be comfortably tackled by formal methods. There have been many problems and failures, but these have nearly always been attributable to inadequate analysis of requirements or inadequate management control. It has turned out that the world just does not suffer significantly from the kind of problem that our research was originally intended to solve.

 

 

 

 

Tony Hoare(토니 호어)

http://codedragon.tistory.com/7976

 

 

 

null pointer

https://en.wikipedia.org/wiki/Null_pointer