Java Pattern.matcher() is a method in the Java Pattern class that creates a Java Matcher object for performing regular expression operations on a given input string. It is used to find matches, check for patterns, or replace parts of the string based on regular expression rules. Introduced in Java 2004 with Java 5, matcher() simplifies text processing tasks such as validation, extraction, and manipulation of strings.

https://docs.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html