Regular Expression Pocket Reference, 2nd Edition

Java (java.util.regex)

Java 1.4 introduced regular expressions with Sun’s java.util.regex package. Although there are competing packages available for previous versions of Java, Sun’s is now the standard. Sun’s package uses a Traditional NFA match engine. For an explanation of the rules behind a Traditional NFA engine, see "Introduction to Regexes and Pattern Matching.” This section covers regular expressions in Java 1.5 and 1.6.