countMatches countMatches(text: String, pattern: String): Number Counts the number of matches in a string. Introduced in DataWeave version 2.4.0. Parameters Name Description text The string to search for matches. pattern A substring to find in the text. Example This example counts matches in a string. Source %dw 2.0 import * from dw::core::Strings output application/json --- "hello worlo!" countMatches "lo" Output 2 countMatches(text: String, pattern: Regex): Number Counts the number of times a regular expression matches text in a string. Introduced in DataWeave version 2.4.0. Parameters Name Description text The string to search for matches. pattern The regex pattern to use in the search. Example This example counts the vowels in a string. Source %dw 2.0 import countMatches from dw::core::Strings output application/json --- "hello, ciao!" countMatches /[aeiou]/ Output 5 countMatches(text: Null, pattern: Any): Null Helper function that enables countMatches to work with a null value. Introduced in DataWeave version 2.4.0.