How to replace a back slash with another character in Java?

Question

I'm trying the following code in Java in which I need to replace a back slash with a forward slash but I can't.

package superpkg;
import java.util.regex.Matcher;

final public class Super
{
    public static void main(String[] args) 
    {
         String string="xxx\\aaa";

         string.replaceAll("\\\\", "/");
         System.out.println(string);

         string.replaceAll(Matcher.quoteReplacement("\\"), "/");
         System.out.println(string);
    }
}

In both the cases, it displays the following output.

xxx\aaa
xxx\aaa

means that the back slash in the given string is not replaced with the forward slash as expected. How can it be achieved?

possible duplicate of [Backslash problem with String.replaceAll](http://stackoverflow.com/questions/1701839/backslash-problem-with-string-replaceall) — ring bearer, Dec 12 '11 at 21:20

score 8 · Accepted Answer · answered Dec 12 '11 at 21:21

8

Strings are immutable in Java. You need to assign the result of replaceAll somewhere:

string = string.replaceAll("\\\\", "/");

answered Dec 12 '11 at 21:21

Oliver Charlesworth

267,707
33
569
680

score 5 · Answer 2 · answered Dec 12 '11 at 21:20

5

Strings are immutable so you need to do

string = string.replaceAll("\\\\", "/");

answered Dec 12 '11 at 21:20

Boiler Bill

1,900
1
22
32

score 3 · Answer 3 · answered Dec 12 '11 at 21:20

3

You are not assigning string its new value. Do this instead string = string.replaceAll("\\\\", "/");

answered Dec 12 '11 at 21:20

GETah

20,922
7
61
103

score 2 · Answer 4 · answered Dec 12 '11 at 21:22

Strings are immutable. There is no mean to modify a string in-place, every method called on String returns a new String.

In your code, string.replaceAll(...) returns a String but you don't reassign it to your "string" variable, so the result is lost. Use this instead :

public class Test {
public static void main(String[] args) {
    String string = "xxx\\aaa";
    string = string.replace("\\", "/");
    System.out.println(string);
    }
}

ring bearer · Answer 5 · 2011-12-12T21:52:13.520

1

java.lang.String is immutable. So you should assign result of your API call to a new variable.

edited Dec 12 '11 at 21:52

answered Dec 12 '11 at 21:24

ring bearer

20,383
7
59
72

score 0 · Answer 6 · answered Dec 12 '11 at 21:36

0

    public static void main(String[] args)  
{ 
     String string="xxx\\aaa"; 

     string = string.replaceAll("\\\\", "/"); 

     System.out.println(string); 
}

answered Dec 12 '11 at 21:36

Michael W

3,515
8
39
62

How to replace a back slash with another character in Java?

6 Answers6