Text processing often involves matching text against a pattern. Although Java s character and assorted string classes offerlow- levelpattern- matching support, that support commonly leads to complex code. To help you write simplerpattern- matching code, Java provides regular expressions. After introducing you to terminology and thejava.util. regex package, Jeff Friesen explores many regular expression constructs supported by that package s Pattern class. Then he examines Pattern s methods and the additionaljava.util. regex classes. In conclusion, he presents a practical application of regular expressions.