[warehouse] A minor refactoring of the class WarehouseWorkerPoolTest (#…

…648)

warehouse/src/test/java/com/usthe/warehouse/WarehouseWorkerPoolTest.java

@@ -1,38 +1,41 @@
 package com.usthe.warehouse;
 
-import org.junit.jupiter.api.Assertions;
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicInteger;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 /**
  * Test case for {@link WarehouseWorkerPool}
  */
 class WarehouseWorkerPoolTest {
+
+    private static final int NUMBER_OF_THREADS = 10;
     private WarehouseWorkerPool pool;
+    private AtomicInteger counter;
+    private CountDownLatch latch;
 
     @BeforeEach
     void setUp() {
         pool = new WarehouseWorkerPool();
+        counter = new AtomicInteger();
+        latch = new CountDownLatch(NUMBER_OF_THREADS);
+
     }
 
     @Test
     void executeJob() throws InterruptedException {
-        int numberOfThreads = 10;
-        AtomicInteger counter = new AtomicInteger();
-        CountDownLatch latch = new CountDownLatch(numberOfThreads);
-
-        for (int i = 0; i < numberOfThreads; i++) {
+        for (int i = 0; i < NUMBER_OF_THREADS; i++) {
             pool.executeJob(() -> {
                 counter.incrementAndGet();
                 latch.countDown();
             });
         }
         latch.await();
 
-        Assertions.assertEquals(numberOfThreads, counter.get());
+        assertEquals(NUMBER_OF_THREADS, counter.get());
     }
 
 }