From d219cb38192c414ec635ab4800464422eaec3d49 Mon Sep 17 00:00:00 2001
From: lehatheslayer <ziqunion95@gmail.com>
Date: Wed, 29 Nov 2023 22:21:16 +0300
Subject: [PATCH]  homework system

---
 src/Homework.java        | 18 ++++++++++++++++++
 src/HomeworkChecker.java | 36 ++++++++++++++++++++++++++++++++++++
 src/HomeworkSystem.java  | 40 ++++++++++++++++++++++++++++++++++++++++
 src/Main.java            | 18 ++++++++++++++++++
 src/Student.java         |  6 ++++++
 5 files changed, 118 insertions(+)
 create mode 100644 src/Homework.java
 create mode 100644 src/HomeworkChecker.java
 create mode 100644 src/HomeworkSystem.java
 create mode 100644 src/Main.java
 create mode 100644 src/Student.java

diff --git a/src/Homework.java b/src/Homework.java
new file mode 100644
index 0000000..dd21f8b
--- /dev/null
+++ b/src/Homework.java
@@ -0,0 +1,18 @@
+import java.time.LocalDateTime;
+
+public record Homework(
+        String content,
+        String authorName,
+        LocalDateTime sendDateTime
+) implements Comparable<Homework> {
+    @Override
+    public int compareTo(Homework o) {
+        if (this.sendDateTime.isAfter(o.sendDateTime)) {
+            return 1;
+        } else if (this.sendDateTime.isBefore(o.sendDateTime)) {
+            return -1;
+        }
+
+        return 0;
+    }
+}
diff --git a/src/HomeworkChecker.java b/src/HomeworkChecker.java
new file mode 100644
index 0000000..5e0583d
--- /dev/null
+++ b/src/HomeworkChecker.java
@@ -0,0 +1,36 @@
+import java.time.LocalDateTime;
+import java.util.Random;
+
+public class HomeworkChecker implements Runnable {
+    private final HomeworkSystem system;
+    private final Random random;
+
+    public HomeworkChecker(HomeworkSystem system) {
+        this.system = system;
+        this.random = new Random();
+    }
+
+    @Override
+    public void run() {
+        while (true) {
+            try {
+                Homework homework = system.getNextHomework();
+                LocalDateTime deadline = system.getDeadline().get();
+
+                int grade = getGradeForHomework(homework, deadline);
+                System.out.printf("%s checker result for homework of student %s: %s%n",
+                        this, homework.authorName(), grade);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+    public int getGradeForHomework(Homework homework, LocalDateTime deadline) {
+        if (homework.sendDateTime().isAfter(deadline)) {
+            return 0;
+        }
+
+        return random.nextInt(6);
+    }
+}
diff --git a/src/HomeworkSystem.java b/src/HomeworkSystem.java
new file mode 100644
index 0000000..198a46d
--- /dev/null
+++ b/src/HomeworkSystem.java
@@ -0,0 +1,40 @@
+import java.time.LocalDateTime;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.PriorityBlockingQueue;
+import java.util.concurrent.Semaphore;
+import java.util.concurrent.atomic.AtomicReference;
+
+public class HomeworkSystem {
+    private final Semaphore semaphore;
+    private final BlockingQueue<Homework> queue;
+    private final AtomicReference<LocalDateTime> deadline;
+
+    public HomeworkSystem(int maxConcurrentCheckers) {
+        this.semaphore = new Semaphore(maxConcurrentCheckers);
+        this.queue = new PriorityBlockingQueue<>();
+        this.deadline = new AtomicReference<>();
+    }
+
+    public void setDeadlineForCurrentHomework(LocalDateTime deadline) {
+        this.deadline.set(deadline);
+    }
+
+    public AtomicReference<LocalDateTime> getDeadline() {
+        return deadline;
+    }
+
+    public void receiveHomework(Homework homework) {
+        queue.add(homework);
+    }
+
+    public Homework getNextHomework() throws InterruptedException {
+        semaphore.acquire();
+        try {
+            Homework homework = queue.take();
+            // Проверка дедлайна
+            return homework;
+        } finally {
+            semaphore.release();
+        }
+    }
+}
diff --git a/src/Main.java b/src/Main.java
new file mode 100644
index 0000000..9d18e26
--- /dev/null
+++ b/src/Main.java
@@ -0,0 +1,18 @@
+import java.time.LocalDateTime;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+public class Main {
+    public static void main(String[] args) {
+        HomeworkSystem system = new HomeworkSystem(5);
+        system.setDeadlineForCurrentHomework(LocalDateTime.now().plusDays(7));
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        for (int i = 0; i < 10; i++) {
+            executor.execute(new HomeworkChecker(system));
+        }
+
+        Student student1 = new Student("Alex");
+        student1.submitHomework(system, new Homework("Math Homework", student1.name(), LocalDateTime.now()));
+    }
+}
\ No newline at end of file
diff --git a/src/Student.java b/src/Student.java
new file mode 100644
index 0000000..51ff15d
--- /dev/null
+++ b/src/Student.java
@@ -0,0 +1,6 @@
+public record Student(String name) {
+
+    public void submitHomework(HomeworkSystem system, Homework homework) {
+        system.receiveHomework(homework);
+    }
+}