Using java.util.regex.Pattern

[Alec Lee]

Why this line

java.util.regex.Pattern.matches("input","input text");

return false?

I'm expecting true for a match. What's wrong with it?

[Jesper de Jong]

Well, the string "input text" simply doesn't match with the regular expression "input". Try this:

boolean result = java.util.regex.Pattern.matches("input.*", "input text");

The regular expression "input.*" means: the letters "input" followed by zero or more arbitrary characters.

[Jeanne Boyarsky]

Pattern pattern = Pattern.compile("input");
Matcher matcher = pattern.matcher("input text");
System.out.println(matcher.matches());
System.out.println(matcher.find());    

Note the different between matches and find. Matches returns false because the entire regular expression doesn't match. Find returns true because the regular expression is found within the string.

Pattern.matches() is shorthand for the first case. There isn't a shorthand method for the second case. But as Jesper noted, you can make your own.