String.replaceAll的正則表達式

Question

我需要一個可與String類的replaceAll方法一起使用的正則表達式，以將*所有實例替換為.*但帶有尾隨\\

即轉換將是

[any character]*[any character] => [any character].*[any character]
* => .*
\* => \* (i.e. no conversion.)

有人可以幫幫我嗎？

Answer 1

使用后向。

String resultString = subjectString.replaceAll("(?<!\\\\)\\*", ".*");

說明：

"(?<!" +     // Assert that it is impossible to match the regex below with the match ending at this position (negative lookbehind)
   "\\\\" +       // Match the character “\” literally
")" +
"\\*"         // Match the character “*” literally

Answer 2

可能沒有捕獲組也可以這樣做，但這應該可行：

myString.replaceAll("\\*([^\\\\]|$)", "*.$1");