Java’s character and assorted string classes offer low-level support for pattern matching, but that support typically leads to complex code. For simpler and more efficient coding, Java offers the Regex API. This two-part tutorial helps you get started with regular expressions and the Regex API. First we’ll unpack the three powerful classes residing in the java.util.regex package, then we’ll explore the Pattern class and its sophisticated pattern-matching constructs.
What are regular expressions?
A regular expression, also known as a regex or regexp, is a string whose pattern (template) describes a set of strings. The pattern determines which strings belong to the set. A pattern consists of literal characters and metacharacters, which are characters that have special meaning instead of a literal meaning.
