How to replace a plus character using Java's String.replaceAll method

Question

What\'s the correct regex for a plus character (+) as the first argument (i.e. the string to replace) to Java\'s replaceAll method in the String class? I can\'t

Answer 1

You need to escape the + for the regular expression, using \.

However, Java uses a String parameter to construct regular expressions, which uses \ for its own escape sequences. So you have to escape the \ itself:

"\\+"

Answer 2

Others have already stated the correct method of:

1. Escaping the + as \\+
2. Using the Pattern.quote method which escapes all the regex meta-characters.

Another method that you can use is to put the + in a character class. Many of the regex meta characters (., *, + among many others) are treated literally in the character class.

So you can also do:

orgStr.replaceAll("[+]",replaceStr);

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