From b0ab2e3fe3ccdb9e6133d86f604f9cbd14be5bbd Mon Sep 17 00:00:00 2001
From: Alexander Chebotin <globaltouareg@gmail.com>
Date: Wed, 29 Nov 2023 14:32:38 +0300
Subject: [PATCH 1/2] Create CheckSystem

Chebotin Alexandr
---
 CheckSystem | 155 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 155 insertions(+)
 create mode 100644 CheckSystem

diff --git a/CheckSystem b/CheckSystem
new file mode 100644
index 0000000..0fdda2a
--- /dev/null
+++ b/CheckSystem
@@ -0,0 +1,155 @@
+
+import java.util.Comparator;
+import java.util.Date;
+import java.util.Random;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.PriorityBlockingQueue;
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class CheckSystem {
+    private static final int NUMBER_OF_TEACHERS = 2;
+    private static final int NUMBER_OF_STUDENTS = 5;
+    private final PriorityBlockingQueue<Hometask> tasks;
+    private final ConcurrentMap<Integer, Result> results;
+
+
+    public CheckSystem() {
+        Comparator<Hometask> comparator = Comparator.comparing(Hometask::getDate);
+        tasks = new PriorityBlockingQueue<>(1, comparator);
+        results = new ConcurrentHashMap<>();
+    }
+
+
+    public static void main(String[] args) {
+        CheckSystem cs = new CheckSystem();
+
+        Teacher[] teachers = new Teacher[NUMBER_OF_TEACHERS];
+        Student[] students = new Student[NUMBER_OF_STUDENTS];
+
+
+        for (int i = 0; i < NUMBER_OF_STUDENTS; i++) {
+            students[i] = new Student(i, cs);
+            new Thread(students[i]).start();
+        }
+
+        for (int i = 0; i < NUMBER_OF_TEACHERS; i++) {
+            teachers[i] = new Teacher(i, cs);
+            new Thread(teachers[i]).start();
+        }
+
+    }
+
+    public PriorityBlockingQueue<Hometask> getTasks() {
+        return tasks;
+    }
+
+    public ConcurrentMap<Integer, Result> getResults() {
+        return results;
+    }
+
+    public Result getResult(Student student) {
+        return results.get(student);
+    }
+}
+
+record Result(Hometask task, int mark) {
+}
+
+class Student extends Thread {
+    private final int studentId;
+    private final CheckSystem cs;
+
+    public Student(int id, CheckSystem cs) {
+        this.studentId = id;
+        this.cs = cs;
+    }
+
+    @Override
+    public void run() {
+        while (true) {
+            try {
+                doHometask();
+                relax();
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+            }
+        }
+    }
+
+    private void doHometask() throws InterruptedException {
+        System.out.println("Student" + studentId + " doing hometask");
+        Thread.sleep(2000);
+        Hometask hometask = new Hometask(new Date(), studentId);
+        cs.getTasks().put(hometask);
+    }
+
+    private void relax() throws InterruptedException {
+        System.out.println("Student" + studentId + " relaxing");
+        Thread.sleep(1000);
+    }
+
+}
+
+class Teacher extends Thread {
+    private final int teacherId;
+    private final CheckSystem cs;
+
+    public Teacher(int id, CheckSystem cs) {
+        this.teacherId = id;
+        this.cs = cs;
+    }
+
+    @Override
+    public void run() {
+        while (true) {
+            try {
+                System.out.println("Waiting for tasks to check");
+                Hometask task = cs.getTasks().take();
+                check(task);
+
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+            }
+
+        }
+    }
+
+    public void check(Hometask task) throws InterruptedException {
+        System.out.println("Teacher" + teacherId + " checking task " + "Hometask" + task.getHometaskId());
+        Thread.sleep(3000);
+
+        Random rand = new Random();
+        Result result = new Result(task, rand.nextInt(100));
+        cs.getResults().put(task.getStudentId(), result);
+    }
+}
+
+class Hometask {
+    private static AtomicInteger count = new AtomicInteger(0);
+    private final AtomicInteger hometaskId = new AtomicInteger(count.getAndIncrement());
+
+    private Date date;
+    private final int studentId;
+
+    public Hometask(Date date, int studentId) {
+        this.date = date;
+        this.studentId = studentId;
+    }
+
+    public Date getDate() {
+        return date;
+    }
+
+    public int getStudentId() {
+        return studentId;
+    }
+
+    public static AtomicInteger getCount() {
+        return count;
+    }
+
+    public AtomicInteger getHometaskId() {
+        return hometaskId;
+    }
+}

From b8deaffa4c2e24981cafd14830913405dac53857 Mon Sep 17 00:00:00 2001
From: Alexander Chebotin <globaltouareg@gmail.com>
Date: Wed, 29 Nov 2023 14:34:25 +0300
Subject: [PATCH 2/2] Rename CheckSystem to CheckSystem.java

---
 CheckSystem => CheckSystem.java | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename CheckSystem => CheckSystem.java (100%)

diff --git a/CheckSystem b/CheckSystem.java
similarity index 100%
rename from CheckSystem
rename to CheckSystem.java