Java regex ignore '.' symbol [duplicate]

Question

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Java RegEx meta character (.) and ordinary dot? (9 answers)

Closed 8 years ago.

I'm trying to split a string at every '.' (period), but periods are a symbol used by java regexes. Example code,

String outstr = "Apis dubli hre. Agro duli demmos,".split(".");

I can't escape the period character, so how else do I get Java to ignore it?

Answer 1

I can't escape the period character, so how else do I get Java to ignore it?

You can escape the period character, but you must first consider how the string is interpreted.

In a Java string (that is fed to Pattern.compile(s))...

• "." is a regex meaning any character.
• "\." is an illegally-escaped string. This won't compile. As a regex in a text editor, however, this is perfectly legitimate, and means a literal dot.
• "\\." is a Java string that, once interpreted, becomes the regular expression \., which is again the escaped (literal) dot.

What you want is

String outstr = "Apis dubli hre. Agro duli demmos,".split("\\.");

Answer 2

Use "\\." instead. Just using . means 'any character'.