Merge pull request #9449 from Maiklins/JAVA-1749-update-UUID-article-and-code

Java-1749 update UUID article and code

core-java-modules/core-java/src/test/java/com/baeldung/uuid/UUIDGeneratorUnitTest.java

@@ -0,0 +1,64 @@
+package com.baeldung.uuid;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.UnsupportedEncodingException;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class UUIDGeneratorUnitTest {
+
+    private static final String NAMESPACE_URL = "6ba7b811-9dad-11d1-80b4-00c04fd430c8";
+    private static final String NAMESPACE_DNS = "6ba7b810-9dad-11d1-80b4-00c04fd430c8";
+
+    @Test
+    public void version_1_UUID_is_generated_with_correct_length_version_and_variant() {
+
+        UUID uuid = UUIDGenerator.generateType1UUID();
+
+        assertEquals(36, uuid.toString().length());
+        assertEquals(1, uuid.version());
+        assertEquals(2, uuid.variant());
+    }
+
+    @Test
+    public void version_3_UUID_is_correctly_generated_for_domain_baeldung_com() throws UnsupportedEncodingException {
+
+        UUID uuid = UUIDGenerator.generateType3UUID(NAMESPACE_DNS, "baeldung.com");
+
+        assertEquals("23785b78-0132-3ac6-aff6-cfd5be162139", uuid.toString());
+        assertEquals(3, uuid.version());
+        assertEquals(2, uuid.variant());
+    }
+
+    @Test
+    public void version_3_UUID_is_correctly_generated_for_domain_d() throws UnsupportedEncodingException {
+
+        UUID uuid = UUIDGenerator.generateType3UUID(NAMESPACE_DNS, "d");
+
+        assertEquals("dbd41ecb-f466-33de-b309-1468addfc63b", uuid.toString());
+        assertEquals(3, uuid.version());
+        assertEquals(2, uuid.variant());
+    }
+
+    @Test
+    public void version_4_UUID_is_generated_with_correct_length_version_and_variant() {
+
+        UUID uuid = UUIDGenerator.generateType4UUID();
+
+        assertEquals(36, uuid.toString().length());
+        assertEquals(4, uuid.version());
+        assertEquals(2, uuid.variant());
+    }
+
+    @Test
+    public void version_5_UUID_is_correctly_generated_for_domain_baeldung_com() throws UnsupportedEncodingException {
+
+        UUID uuid = UUIDGenerator.generateType5UUID(NAMESPACE_URL, "baeldung.com");
+
+        assertEquals("aeff44a5-8a61-52b6-bcbe-c8e5bd7d0300", uuid.toString());
+        assertEquals(5, uuid.version());
+        assertEquals(2, uuid.variant());
+    }
+}