[JAVA-10432] Rename and enable testng-command-line module

testing-modules/testng-command-line/src/main/java/com/baeldung/testng/DateSerializerService.java

@@ -0,0 +1,11 @@
+package com.baeldung.testng;
+
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
+public class DateSerializerService {
+    public String serializeDate(Date date, String format) {
+        SimpleDateFormat dateFormat = new SimpleDateFormat(format);
+        return dateFormat.format(date);
+    }
+}

testing-modules/testng-command-line/src/test/java/com/baeldung/testng/DateSerializerServiceUnitTest.java

@@ -0,0 +1,24 @@
+package com.baeldung.testng;
+
+import java.util.Date;
+
+import com.baeldung.testng.DateSerializerService;
+import org.testng.annotations.BeforeClass;
+import org.testng.annotations.Test;
+
+@Test(testName = "Date Serializer")
+public class DateSerializerServiceUnitTest {
+    private DateSerializerService toTest;
+
+    @BeforeClass
+    public void beforeClass() {
+        toTest = new DateSerializerService();
+    }
+
+    @Test(expectedExceptions = { NullPointerException.class })
+    void givenNullDate_whenSerializeDate_thenThrowsException() {
+        Date dateToTest = null;
+
+        toTest.serializeDate(dateToTest, "yyyy/MM/dd HH:mm:ss.SSS");
+    }
+}