Java开发网 - 一道简单题，分析一下

Topic: 一道简单题，分析一下

1.一道简单题，分析一下

Posted by: lzx17
Posted on: 2006-05-28 11:24

What will be the result of executing the following code?

1. boolean a = true;

2. boolean b = false;

3. boolean c = true;

4. if (a == true)

5. if (b == true)

6. if (c == true) System.out.println("Some things are true in this world");

7. else System.out.println("Nothing is true in this world!");

8. else if (a && (b = c)) System.out.println("It's too confusing to tell what is true and what is false");

9. else System.out.println("Hey this won't compile");

Choices:

a. The code won't compile

b. "Some things are true in this world" will be printed

c. "Hey this won't compile" will be printed

d. None of these

应该选 c吧，答案是d

2.Re:一道简单题，分析一下 [Re: lzx17]	Copy to clipboard
Posted by: hust_need4speed Posted on: 2006-05-28 18:38 这题你自己试试不就知道了，答案是D。题目的代码没有使用缩进(indent)，所以看起来麻烦点。这题考的是不带 {} 的 if 的覆盖范围。

3.Re:一道简单题，分析一下 [Re: lzx17]	Copy to clipboard
Posted by: lyn0948 Posted on: 2006-05-30 09:58 大哥，自己编辑一下，运行一下不就知道了吗？我感觉是没有答案。 ("It's too confusing to tell what is true and what is false"); 才是正确的答案，在考SCJP的过程中，有好多答案都是错误的所以，你最好自己到计算机上运行一下这样才放心哈哈

4.Re:一道简单题，分析一下 [Re: lzx17]	Copy to clipboard
Posted by: gutxgc Posted on: 2006-06-01 17:04 自己分析一下给人家看一下吗不然给你答案又怎么样啊你只想知道答案你自己编辑一下就OK了不用来这里问了

5.Re:一道简单题，分析一下 [Re: lzx17]

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Posted by: hzx002
Posted on: 2006-06-02 16:05

boolean a = true;
boolean b = false;
boolean c = true;

if (a == true){ // 1
  if (b == true){ // 2
    if (c == true) { // 3
      System.out.println("Some things are "
        + "true in this world");
    } // 3 if end here

    else { //此 else 与 3 匹配
      System.out.println("Nothing is true "
        + "in this world!");
    }
  } // 2 if end here

  else if (a && (b = c)){ // 此 else if 与 2 匹配
    System.out.println("It's too confusing to "
      +"tell what is true and what is false");
  }

  else { // 与 2 匹配的 else
    System.out.println("Hey this won't compile");
  }
} // 1 end here

我已经改了一下，但没有改变程序的执行顺序
你自己看吧。注意：
//2 是
if()...
else if()...
else.....
结构；还有 (a && (b = c))
的值为真,所以是：It's too confusing to tell what is true and what is false