In This Chapter
Introducing regular expressions
Trying out regular expressions with a helpful program
Creating simple expressions that match patterns of characters
Using regular expression features such as custom classes, quantifiers, and groups
Using regular expressions with the String class
Using the Pattern and Matcher classes for more-extensive regular expressions
Regular expressions are not expressions that have a lot of fiber in their diet. Instead, a regular expression is a special type of pattern-matching string that can be very useful for programs that do string manipulation. Regular expression strings contain special pattern-matching characters that can be matched against another string to see whether the other string fits the pattern. Regular expressions are very handy for doing complex data validation — for making sure that users enter ...