In this example we will show how to count the number of times an element appears within a list. For seed data in the first snippet we used common gridiron football sport names and populated a list from 1 to 10 for the second. In both snippets we will use list.count passing a groovy closure with a clause. You can consider the count a short cut to filtering and finding the size of an arraylist. A comparable example demonstrates how to count the frequency of string or numbers in arraylist using java.
Count string starts with and contains
@Test
void count_elements_in_list () {
def list = ["Six-man football", "Sprint", "Touch football"]
def frequency = list.count { it.startsWith("S") && it.contains("football") }
assert 1 == frequency
}Count numbers greater than 7
@Test
void count_elements_gt_value() {
def listOfNumbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
def rate = listOfNumbers.count { it > 7 }
assert 3 == rate
}