lambda expression java
public class TestLambda { public static void main(String args[]) { List<String> lowerCaseStringsList = Arrays.asList("a","b","c"); // the :: notation is the lambda expression // it's the same as the anonymous function s -> s.toUpperCase() List<String> upperCaseStringsList = lowerCaseStringsList.stream(). map(String::toUpperCase). collect(Collectors.toList()); } }