如何在一个句子中多次使用参考文献？

Question

I have the code shown below.

StringBuffer sb = new StringBuffer(Integer.toBinaryString(n));

return (sb.charAt(sb.length() - k) == '1') ? Integer.parseInt(sb.deleteCharAt(sb.length() - k).insert(sb.length() - (k + 1), 0).toString(),2) : n;

Is it possible to use the sb reference implicitly, ie just in order to write only the return sentence?

Answer 1

The only way you can "implicitly" use such a reference is when a method returns this (ie the object you call it on) to allow that kind of call chaining. For example StringBuilder.deleteCharAt() does this and you already make use of this by chaining a call to insert :

sb.deleteCharAt(...).insert(...)

This kind of return value only makes sense in method that don't have any other return value to give (ie you obviously can't do that with sb.charAt , because that returns a char and can't also return the StringBuilder itself).

But if you want to know if you can get rid of the sb in sb.length() for example: no, you pretty much can't.