part 1 ,part 2, part 3 LambdaExercise are done ( Yuriy Korovko)

src/main/java/data/Generator.java

@@ -60,7 +60,8 @@ public static Employee generateEmployee() {
     }
 
     public static List<Employee> generateEmployeeList() {
-        // TODO
-        throw new UnsupportedOperationException();
+       return Stream.generate(Generator::generateEmployee)
+            .limit(10)
+            .collect(toList());
     }
 }

src/test/java/part1/exercise/StreamsExercise1.java

@@ -1,6 +1,7 @@
 package part1.exercise;
 
 import data.Employee;
+import data.Generator;
 import data.JobHistoryEntry;
 import data.Person;
 import org.junit.Test;
@@ -15,6 +16,9 @@
 import static java.util.stream.Collectors.groupingBy;
 import static java.util.stream.Collectors.mapping;
 import static java.util.stream.Collectors.toList;
+import static org.junit.Assert.assertEquals;
+
+import javax.naming.ldap.LdapName;
 
 public class StreamsExercise1 {
     // https://youtu.be/kxgo7Y4cdA8 Сергей Куксенко и Алексей Шипилёв — Через тернии к лямбдам, часть 1
@@ -25,16 +29,49 @@ public class StreamsExercise1 {
 
     @Test
     public void getAllEpamEmployees() {
-        List<Person> epamEmployees = null;// TODO all persons with experience in epam
-        throw new UnsupportedOperationException();
+        // TODO all persons with experience in epam
+        final List<Employee> employeeList = Generator.generateEmployeeList();
+
+        List<Person> actualPersonList = employeeList.stream()
+            .filter(employee -> employee.getJobHistory().stream()
+                .map(JobHistoryEntry::getEmployer)
+                .anyMatch("epam"::equalsIgnoreCase)
+            )
+            .map(Employee::getPerson)
+            .collect(toList());
+
+        List<Person> expectedPersonList = new ArrayList<>();
+        for (Employee employee : employeeList) {
+            for (JobHistoryEntry historyEntry : employee.getJobHistory()) {
+                if (historyEntry.getEmployer().equalsIgnoreCase("epam")) {
+                    expectedPersonList.add(employee.getPerson());
+                    break;
+                }
+            }
+        }
+        assertEquals(actualPersonList.size(), expectedPersonList.size());
     }
 
     @Test
     public void getEmployeesStartedFromEpam() {
-        List<Person> epamEmployees = null;// TODO all persons with first experience in epam
-        throw new UnsupportedOperationException();
+        // TODO all persons with first experience in epam
+        final List<Employee> employeeList = Generator.generateEmployeeList();
+        List<Person> epamEmployees = employeeList.stream()
+            .filter(e -> e.getJobHistory().stream().limit(1).collect(toList()).get(0).getEmployer().equals("epam"))
+            .map(Employee::getPerson)
+            .collect(Collectors.toList());
+        List<Person> expectedList = new ArrayList<>();
+
+        for (Employee anEmployeeList : employeeList) {
+            if (anEmployeeList.getJobHistory().get(0).getEmployer().equalsIgnoreCase("epam")) {
+
+                expectedList.add(anEmployeeList.getPerson());
+            }
+        }
+        assertEquals(expectedList, epamEmployees);
     }
 
+
     @Test
     public void sumEpamDurations() {
         final List<Employee> employees = generateEmployeeList();
@@ -49,11 +86,12 @@ public void sumEpamDurations() {
             }
         }
 
-        // TODO
-        throw new UnsupportedOperationException();
-
-        // int result = ???
-        // assertEquals(expected, result);
+        final int result = employees.stream()
+            .flatMap(employee -> employee.getJobHistory().stream())
+            .filter(j -> j.getEmployer().equals("epam"))
+            .mapToInt(JobHistoryEntry::getDuration)
+            .sum();
+        assertEquals(expected, result);
     }
 
 }