Lesson_9

proJect/pom.xml

@@ -11,6 +11,18 @@
         <maven.compiler.source>11</maven.compiler.source>
         <maven.compiler.target>11</maven.compiler.target>
     </properties>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>16</source>
+                    <target>16</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
 
 
 </project>

proJect/src/main/java/anlov/java/FifthExercise.java

@@ -0,0 +1,24 @@
+package anlov.java;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Scanner;
+import java.util.stream.Collectors;
+
+public class FifthExercise {
+
+    private static final List<String> logins = new ArrayList<>();
+
+    public static List<String> getLogins() {
+        Scanner scanner = new Scanner(System.in);
+
+        while (true) {
+            String login = scanner.nextLine();
+            if (login.isEmpty()) {
+                break;
+            }
+            logins.add(login);
+        }
+        return logins.stream().filter(s -> s.startsWith("f")).collect(Collectors.toList());
+    }
+}

proJect/src/main/java/anlov/java/FirstExercise.java

@@ -0,0 +1,12 @@
+package anlov.java;
+
+
+import static java.util.Arrays.stream;
+
+public class FirstExercise {
+
+    public static long getChet(int[] nums) {
+        return stream(nums).filter(n -> n % 2 == 0).count();
+
+    }
+}

proJect/src/main/java/anlov/java/FourthExercise.java

@@ -0,0 +1,86 @@
+package anlov.java;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
+
+public class FourthExercise {
+
+    Collection<Student> students = Arrays.asList(
+            new Student("Дмитрий", 17, Gender.MAN),
+            new Student("Максим", 20, Gender.MAN),
+            new Student("Екатерина", 20, Gender.WOMAN),
+            new Student("Михаил", 28, Gender.MAN)
+    );
+
+    private enum Gender {
+        MAN,
+        WOMAN
+    }
+
+    private static class Student {
+        private final String name;
+        private final Integer age;
+        private final Gender gender;
+
+        public Student(String name, Integer age, Gender gender) {
+            this.name = name;
+            this.age = age;
+            this.gender = gender;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public Integer getAge() {
+            return age;
+        }
+
+        public Gender getGender() {
+            return gender;
+        }
+
+        @Override
+        public String toString() {
+            return "{" +
+                    "name='" + name + '\'' +
+                    ", age=" + age +
+                    ", gender=" + gender +
+                    '}';
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (!(o instanceof Student)) return false;
+            Student student = (Student) o;
+            return Objects.equals(name, student.name) &&
+                    Objects.equals(age, student.age) &&
+                    Objects.equals(gender, student.gender);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(name, age, gender);
+        }
+
+    }
+
+    public double middleAge() {
+        return students.stream().filter(student -> student.getGender() == Gender.MAN)
+                .mapToDouble(Student::getAge)
+                .average()
+                .orElseThrow(() -> new IllegalStateException("Нет студентов мужского пола!"));
+    }
+
+    public List<String> wantsToArmy() {
+        return students.stream()
+                .filter(student -> student.getGender() == Gender.MAN)
+                .filter(student -> student.getAge() >= 18 && student.getAge() <= 27)
+                .map(Student::getName)
+                .collect(Collectors.toList());
+    }
+}

proJect/src/main/java/anlov/java/Main.java

@@ -2,8 +2,31 @@
 
 
 import java.util.Arrays;
+import java.util.List;
 
 public class Main {
     public static void main(String[] args) {
+
+        // 1 задание
+        int[] abc = new int[]{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12};
+        System.out.println(FirstExercise.getChet(abc));
+
+        // 2 задание
+        List<String> strings = List.of("Highload", "High", "Load", "Highload", "High");
+        System.out.println(SecondExercise.countOfWord(strings, "High"));
+        System.out.println(SecondExercise.firstElement(strings));
+        System.out.println(SecondExercise.lastElement(strings));
+
+        // 3 задание
+        List<String> strings1 = List.of("f10", "f4", "f15", "f2", "f4");
+        System.out.println(Arrays.toString(ThirdExercise.sortedStrings(strings1)));
+
+        // 4 задание
+        FourthExercise fourthExercise = new FourthExercise();
+        System.out.println(fourthExercise.middleAge());
+        System.out.println(fourthExercise.wantsToArmy());
+
+        // 5 задание
+        System.out.println(FifthExercise.getLogins());
     }
 }

proJect/src/main/java/anlov/java/SecondExercise.java

@@ -0,0 +1,18 @@
+package anlov.java;
+
+import java.util.List;
+
+public class SecondExercise {
+
+    public static long countOfWord(List<String> strings, String word) {
+        return strings.stream().filter(x -> x.equals(word)).count();
+    }
+
+    public static String firstElement(List<String> strings) {
+        return strings.stream().findFirst().orElse("0");
+    }
+
+    public static String lastElement(List<String> strings) {
+        return strings.stream().skip(strings.size() - 1).findFirst().orElse("0");
+    }
+}

proJect/src/main/java/anlov/java/ThirdExercise.java

@@ -0,0 +1,11 @@
+package anlov.java;
+
+
+import java.util.List;
+
+public class ThirdExercise {
+
+    public static String[] sortedStrings(List<String> strings) {
+       return strings.stream().sorted().toArray(String[]::new);
+    }
+}