Programming Groovy 2

6.4 Other Convenience Methods on ​List​s

Groovy adds a number of convenience methods to ​Collections​. (For a list, refer to ​http://groovy.codehaus.org/groovy-jdk/java/util/Collection.html​ .) Let’s implement an example using the method we’re already familiar with— ​each​ . Then we’ll refactor that example using methods that will make our code self-contained and expressive. Along the way, we’ll see how Groovy treats code blocks as first-class citizens, like functional programming languages do.

Suppose we have a collection of strings and want to count the total number of characters. Here’s a way to do that using the ​each​ method:

lst = ['Programming', 'In', 'Groovy']