正则表达式替换 java 中 csv 字符串中的空值

Question

I have a string with value我有一个带值的字符串

 "ABC","ONE", "Hello",,,"2019"

I want to replace two consecutively empty values in a CSV file with * .我想用*替换 CSV 文件中的两个连续空值。

Expected output:预期 output：

 "ABC","ONE", "Hello","*","*","2019"

This is what I tried,这是我试过的，

line.replaceAll(",,","\"*\"");

But this gives me below output, replacing on first occurrence但这给了我低于 output，第一次出现替换

"ABC","ONE", "Hello","*","2019"

Answer 1

You may use a regex with lookahead and lookbehind:您可以使用带有前瞻和后视的正则表达式：

(?<=,)(?=,)

And replace it with "*"并将其替换为"*"

Java Code: Java 代码：

repl = str.replaceAll("(?<=,)(?=,)", "\"*\"");