我问他为啥用 " null != x "?
he said he uses null == x in if statements becase it is easy to mistakenly write if ( x = null ) instead of if ( x == null ), both compile; However, null = x does not compile
and to be consistent, he use null != x
我心想: K, 这多ugly啊,你要能记住每次都倒过来,为啥记不住 x equal equal null?