Add SumSalaryDeptWiseQ17 class to calculate total salary by department

Author: kumarcodes

src/main/java/com/superthirty/SumSalaryDeptWiseQ17.java

@@ -0,0 +1,14 @@
+package com.superthirty;
+
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+public class SumSalaryDeptWiseQ17 {
+    public static void main(String[] args) {
+        List<Employee> employees = EmployeeDTO.getEmployees();
+        Map<String, Double> sumMap =  employees.stream().collect(Collectors.groupingBy(
+                Employee::getDepartment,Collectors.summingDouble(Employee::getSalary)));
+        System.out.println(sumMap);
+    }
+}