How to replace "\" with "/" in java? [duplicate]

Question

I have a string like s = "abc\def" and I want to replace "" with "/" and makes the string like "abc/def/".

I tried replaceAll("\\","/") but the compiler is giving error for string

error: illegal escape character String s="abc\def";

Answer 1

The issue is that Java uses \ as the string escape character, but also as the regex escape character, and replaceAll performs a regex search. So you need to doubly escape the backslash (once to make it a literal \ in the string, and once to make it a literal character in the regular expression):

result = str.replaceAll("\\\\", "/");

Alternatively, you don’t actually need regular expressions here, so the following works as well:

result = str.replace("\\", "/");

Or, indeed, using the single-char replacement version:

result = str.replace('\\', '/');