Top Java8 Stream Grouping by Interview Questions with examples
1. How do you group strings by their length? Map<Integer, List<String>> grouped = list.stream() .collect(Collectors.groupingBy(String::length)); 2. How do you group numbers by even and odd? Map<String, List<Integer>> grouped = numbers.stream() .collect(Collectors.groupingBy(n -> n % 2 == 0 ? “Even” : “Odd”)); 3. How do you group employees by department? Map<String, List<Employee>> grouped = employees.stream() .collect(Collectors.groupingBy(Employee::getDepartment)); […]