Java语言的科学与艺术

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• In J.K. Rowling's Harry Potter and the Chamber of Secrets, Arthur Weasley warns that you should "never trust anything that can think for itself if you can't see where it keeps its brain." While that may be sage advice in the wizarding world, programmers must often do precisely that. ... In fact, one of the great advantages of methods is that you can use them without having to understand the complexity that goes on underneath. Methods provide a way of hiding lower-level implementation details so that the caller need not be bothered by them. (查看原文)

  [已注销] 2014-05-05 01:47:33

• One particularly important example is the equals method, which is defined in the universal class Object and can therefore be applied to any object. The equals method asked whether one object has the same value as another. By contrast, the == operator asks whether its operands are precisely the same object, which is not ordinarily as userful. ... String answer = readLine("Would you like instructions?"); Once the user enters a response, the question is how would you determine whether that answer was "yes" or "no" or perhaps some other string entirely. The following approach doesn't work. if (answer == "yes") ... ... The statement you need to write is if (answer.equals("yes")) (查看原文)

  [已注销] 2014-05-05 02:34:02