lab8

2024-10-20 18:57:35 +03:00
parent b6de049094
commit 5bae7a279b
7 changed files with 461 additions and 4 deletions
--- a/src/test/java/MySemaphoreTest.java
+++ b/src/test/java/MySemaphoreTest.java
@@ -0,0 +1,112 @@
+import org.junit.jupiter.api.Test;
+import ru.lionarius.sync.MySemaphore;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class MySemaphoreTest {
+    @Test
+    void testInitialization() {
+        assertDoesNotThrow(() -> new MySemaphore(-1));
+        assertDoesNotThrow(() -> new MySemaphore(0));
+        var semaphore = new MySemaphore(5);
+        assertEquals(5, semaphore.availablePermits());
+    }
+
+    @Test
+    void testAcquireAndRelease() throws InterruptedException {
+        var semaphore = new MySemaphore(2);
+        assertEquals(2, semaphore.availablePermits());
+        semaphore.acquire();
+        assertEquals(1, semaphore.availablePermits());
+        semaphore.acquire();
+        assertEquals(0, semaphore.availablePermits());
+        assertFalse(semaphore.tryAcquire());
+        semaphore.release();
+        assertEquals(1, semaphore.availablePermits());
+        assertTrue(semaphore.tryAcquire());
+        assertEquals(0, semaphore.availablePermits());
+    }
+
+    @Test
+    void testTryAcquire() {
+        var semaphore = new MySemaphore(2);
+        assertTrue(semaphore.tryAcquire());
+        assertEquals(1, semaphore.availablePermits());
+        assertTrue(semaphore.tryAcquire());
+        assertEquals(0, semaphore.availablePermits());
+        assertFalse(semaphore.tryAcquire());
+        assertEquals(0, semaphore.availablePermits());
+    }
+
+    @Test
+    void testMultipleThreads() throws InterruptedException {
+        final int THREAD_COUNT = 10;
+        final int PERMITS = 3;
+        var semaphore = new MySemaphore(PERMITS);
+        var startLatch = new CountDownLatch(1);
+        var finishLatch = new CountDownLatch(THREAD_COUNT);
+        var concurrentThreads = new AtomicInteger(0);
+        var maxConcurrentThreads = new AtomicInteger(0);
+
+        for (int i = 0; i < THREAD_COUNT; i++) {
+            new Thread(() -> {
+                try {
+                    startLatch.await();
+                    semaphore.acquire();
+                    int current = concurrentThreads.incrementAndGet();
+                    maxConcurrentThreads.updateAndGet(max -> Math.max(max, current));
+                    Thread.sleep(100); // Имитация работы
+                    concurrentThreads.decrementAndGet();
+                    semaphore.release();
+                    finishLatch.countDown();
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                }
+            }).start();
+        }
+
+        startLatch.countDown();
+        assertTrue(finishLatch.await(5, TimeUnit.SECONDS));
+        assertEquals(PERMITS, maxConcurrentThreads.get());
+        assertEquals(PERMITS, semaphore.availablePermits());
+    }
+
+    @Test
+    void testBlockingAcquire() throws InterruptedException {
+        var semaphore = new MySemaphore(1);
+        semaphore.acquire();
+        assertEquals(0, semaphore.availablePermits());
+
+        var thread = new Thread(() -> {
+            try {
+                semaphore.acquire();
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+            }
+        });
+
+        thread.start();
+        Thread.sleep(100); // Даем время потоку начать ожидание
+        assertTrue(thread.isAlive());
+        assertEquals(0, semaphore.availablePermits());
+
+        semaphore.release();
+        thread.join(1000);
+        assertFalse(thread.isAlive());
+        assertEquals(0, semaphore.availablePermits());
+    }
+
+    @Test
+    void testAvailablePermits() {
+        var semaphore = new MySemaphore(5);
+        assertEquals(5, semaphore.availablePermits());
+        semaphore.tryAcquire();
+        assertEquals(4, semaphore.availablePermits());
+        semaphore.release();
+        assertEquals(5, semaphore.availablePermits());
+    }
+}