BAEL-3459: Introduction to cache2k (#8651)

libraries-3/src/test/java/com/baeldung/cache2k/ProductHelperUnitTest.java

@@ -0,0 +1,17 @@
+package com.baeldung.cache2k;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+public class ProductHelperUnitTest {
+
+    ProductHelper productHelper = new ProductHelper();
+
+    @Test
+    public void whenInvokedGetDiscount_thenGetItFromCache() {
+        assertTrue(productHelper.getDiscount("Sports") == 20);
+        assertTrue(productHelper.getDiscount("Electronics") == 0);
+    }
+
+}

libraries-3/src/test/java/com/baeldung/cache2k/ProductHelperUsingLoaderUnitTest.java

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+package com.baeldung.cache2k;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+public class ProductHelperUsingLoaderUnitTest {
+
+    ProductHelperUsingLoader productHelper = new ProductHelperUsingLoader();
+
+    @Test
+    public void whenInvokedGetDiscount_thenPopulateCache() {
+        assertTrue(productHelper.getDiscount("Sports") == 20);
+        assertTrue(productHelper.getDiscount("Electronics") == 10);
+    }
+
+}

libraries-3/src/test/java/com/baeldung/cache2k/ProductHelperWithEventListenerUnitTest.java

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+package com.baeldung.cache2k;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+public class ProductHelperWithEventListenerUnitTest {
+
+    ProductHelperWithEventListener productHelper = new ProductHelperWithEventListener();
+
+    @Test
+    public void whenEntryAddedInCache_thenEventListenerCalled() {
+        assertTrue(productHelper.getDiscount("Sports") == 20);
+    }
+
+}

libraries-3/src/test/java/com/baeldung/cache2k/ProductHelperWithExpiryUnitTest.java

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+package com.baeldung.cache2k;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+public class ProductHelperWithExpiryUnitTest {
+
+    ProductHelperWithExpiry productHelper = new ProductHelperWithExpiry();
+
+    @Test
+    public void whenInvokedGetDiscountForExpiredProduct_thenNoDiscount() throws InterruptedException {
+        assertTrue(productHelper.getDiscount("Sports") == 20);
+        Thread.sleep(20);
+        assertTrue(productHelper.getDiscount("Sports") == 0);
+    }
+
+}