String index out of range with replace all

Question

How can I replace mapDir surrounded by <> to a certain string?

  String mapDir = "D:\\mapping\\specialists\\ts_gpc\\";
  String test = "foo: <mapDir> -bar";
  println(test.replaceAll("<mapDir>", mapDir));

The above gives me a StringIndexOutOfBoundsException.

This code below for me, but I think pure java has to work as well.

static String replaceWord(String original, String find, String replacement) {
    int i = original.indexOf(find);
    if (i < 0) {
        return original;  // return original if 'find' is not in it.
    }

    String partBefore = original.substring(0, i);
    String partAfter  = original.substring(i + find.length());

    return partBefore + replacement + partAfter;
}

You need to quote (Pattern.quote) the first argument of replaceAll, as it is a regex. — Gábor Bakos, Nov 22 '14 at 13:17
Check out this post http://stackoverflow.com/questions/18875852/why-string-replaceall-in-java-requires-4-slashes-in-regex-to-actually-r/ — gashu, Nov 22 '14 at 13:38

score 6 · Accepted Answer · answered Nov 22 '14 at 13:20

6

You dont need replaceAll method as you are not using regex. Instead you could work with replace api like below:

String mapDir = "D:\\mapping\\specialists\\ts_gpc\\";
String test = "foo: <mapDir> -bar";
System.out.println(test.replace("<mapDir>", mapDir));

answered Nov 22 '14 at 13:20

SMA

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Exactly. That `all` in `replaceAll` does not mean, that it replaces all occurrences of the searched string, whereas `replace` replaces only the first one. They both replace *all* occurrences. – Tom Nov 22 '14 at 13:23

score 3 · Answer 2 · answered Nov 22 '14 at 13:25

replaceAll in String uses a regex, as specified in the documentation:

Note that backslashes () and dollar signs ($) in the replacement string may cause the results to be different than if it were being treated as a literal replacement string; see Matcher.replaceAll. Use Matcher.quoteReplacement(java.lang.String) to suppress the special meaning of these characters, if desired.

Thus, you should escape your replacement string like this:

String mapDir = "D:\\mapping\\specialists\\ts_gpc\\";
String test = "foo: <mapDir> -bar";
System.out.println(test.replaceAll("<mapDir>", Matcher.quoteReplacement(mapDir)));

which gives the output:

foo: D:\mapping\specialists\ts_gpc\ -bar

score 0 · Answer 3 · edited May 23 '17 at 11:59

Since replaceAll works with regex, you need to re-escape the backslashes:

String mapDir = "D:\\\\mapping\\\\specialists\\\\ts_gpc\\\\";
String test = "foo: <mapDir> -bar";
System.out.println(test.replaceAll("<mapDir>", mapDir));

Quoting this answer:

by the time the regex compiler sees the pattern you've given it, it sees only a single backslash (since Java's lexer has turned the double backwhack into a single one)

String index out of range with replace all

3 Answers3