I have two strings
string1 = 44.365 Online order
and string2 = 0 Request Delivery. Now I would like to apply a regular expression to these strings that filters out everything but numbers so I get integers like string1 = 44365 and string2 = 0.
How can I accomplish this?
You can make use of the ^. It considers everything apart from what you have infront of it.
So if you have [^y] its going to filter everything apart from y. In your case you would do something like
String value = string.replaceAll("[^0-9]","");
where string is a variable holding the actual text!
\D would 67% shorter as a pattern. ;)
- so something like [^-?0-9] should do the trick. -? there tells the regex engine to match - if it exists(0 or none).String clean1 = string1.replaceAll("[^0-9]", "");
or
String clean2 = string2.replaceAll("[^\\d]", "");
Where \d is a shortcut to [0-9] character class,
or
String clean3 = string1.replaceAll("\\D", "");
Where \D is a negation of the \d class (which means [^0-9])
string1 = string1.replaceAll("[^0-9]", "");
string2 = string2.replaceAll("[^0-9]", "");This is the Google Guava #CharMatcher Way.
String alphanumeric = "12ABC34def";
String digits = CharMatcher.JAVA_DIGIT.retainFrom(alphanumeric); // 1234
String letters = CharMatcher.JAVA_LETTER.retainFrom(alphanumeric); // ABCdef
If you only care to match ASCII digits, use
String digits = CharMatcher.inRange('0', '9').retainFrom(alphanumeric); // 1234
If you only care to match letters of the Latin alphabet, use
String letters = CharMatcher.inRange('a', 'z')
.or(inRange('A', 'Z')).retainFrom(alphanumeric); // ABCdef
