sortowanie i minmax funkcyjnie

src/main/java/emps/F5_MinMax_Liczby.java

+package emps;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class F5_MinMax_Liczby {
+    public static void main(String[] args) {
+        List<Employee> emps = ObslugaCSV.wczytaj();
+
+        int min = emps.stream()
+                .mapToInt(Employee::getSalary)
+                .min()
+                .orElse(0);
+
+        int max = emps.stream()
+                .mapToInt(Employee::getSalary)
+                .max()
+                .orElse(0);
+
+        System.out.println("Minimalna pensja: " + min);
+        System.out.println("Maksymalna pensja: " + max);
+    }
+}

src/main/java/emps/F5_MinMax_Obiekty.java

+package emps;
+
+import java.util.Comparator;
+import java.util.List;
+import java.util.Optional;
+
+public class F5_MinMax_Obiekty {
+    public static void main(String[] args) {
+        List<Employee> emps = ObslugaCSV.wczytaj();
+
+        Optional<Employee> min = emps.stream().min(Comparator.comparingInt(Employee::getSalary));
+        if(min.isPresent()) {
+            Employee emp = min.get();
+            System.out.println("Najmniej czyli " + emp.getSalary() + " zarabia " + emp.getFirstName() + " " + emp.getLastName());
+        }
+
+        Optional<Employee> max = emps.stream().max(Comparator.comparingInt(Employee::getSalary));
+        if(max.isPresent()) {
+            Employee emp = max.get();
+            System.out.println("Najwięcej czyli " + emp.getSalary() + " zarabia " + emp.getFirstName() + " " + emp.getLastName());
+        }
+        // Inne podejścia do korzystania z Optionali będą w przykładach "sprzedaz"
+    }
+}

src/main/java/emps/F6_Sortowanie.java

+package emps;
+
+import java.util.Comparator;
+import java.util.List;
+
+public class F6_Sortowanie {
+
+    public static void main(String[] args) {
+        List<Employee> emps = ObslugaCSV.wczytaj();
+        emps.stream()
+                .sorted(Comparator.comparingInt(Employee::getSalary).reversed())
+                .map(emp -> String.format("%s %s (%s) zarabia %d",
+                        emp.getFirstName(), emp.getLastName(), emp.getJobTitle(), emp.getSalary()))
+                .forEach(System.out::println);
+    }
+}

src/main/java/emps/F7_UnikalneMiasta.java

+package emps;
+
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+public class F7_UnikalneMiasta {
+
+	public static void main(String[] args) {
+		List<Employee> emps = ObslugaCSV.wczytaj();
+		
+		// podejście 1 - tworzymy Set
+		Set<String> miasta = emps.stream()
+				.map(Employee::getCity)
+				.collect(Collectors.toSet());
+		
+		System.out.println("Mam zbiór o rozmiarze " + miasta.size());
+		miasta.forEach(m -> System.out.println("- " + m));
+		
+		System.out.println();
+		
+		// podejście 2 - usuwanie duplikatów i wypisywanie "w locie"
+		emps.stream()
+			.map(Employee::getCity)
+			.distinct()
+			.forEach(m -> System.out.println("* " + m));
+	}
+
+}