setup tests for HelloWorldService

src/test/java/com/example/service/HelloWorldServiceImplTest.java

@@ -0,0 +1,158 @@
+package com.example.service;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.DisplayName;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * Unit tests for HelloWorldServiceImpl
+ * Tests the basic Hello World API functionality
+ */
+@DisplayName("HelloWorldServiceImpl Tests")
+class HelloWorldServiceImplTest {
+
+    private HelloWorldServiceImpl service;
+
+    @BeforeEach
+    void setUp() {
+        service = new HelloWorldServiceImpl();
+    }
+
+    @Test
+    @DisplayName("Should return greeting with valid name")
+    void testGetHelloWorld_WithValidName() {
+        // Arrange
+        String name = "John";
+        String expected = "Hello World, John!";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertEquals(expected, result);
+    }
+
+    @Test
+    @DisplayName("Should return greeting with empty string")
+    void testGetHelloWorld_WithEmptyString() {
+        // Arrange
+        String name = "";
+        String expected = "Hello World, !";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertEquals(expected, result);
+    }
+
+    @Test
+    @DisplayName("Should handle null input gracefully")
+    void testGetHelloWorld_WithNull() {
+        // Arrange
+        String name = null;
+        String expected = "Hello World, null!";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertEquals(expected, result);
+    }
+
+    @Test
+    @DisplayName("Should handle special characters in name")
+    void testGetHelloWorld_WithSpecialCharacters() {
+        // Arrange
+        String name = "Alice@123";
+        String expected = "Hello World, Alice@123!";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertEquals(expected, result);
+    }
+
+    @Test
+    @DisplayName("Should handle names with spaces")
+    void testGetHelloWorld_WithSpaces() {
+        // Arrange
+        String name = "John Doe";
+        String expected = "Hello World, John Doe!";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertEquals(expected, result);
+    }
+
+    @Test
+    @DisplayName("Should handle long names")
+    void testGetHelloWorld_WithLongName() {
+        // Arrange
+        String name = "ThisIsAVeryLongNameForTestingPurposes";
+        String expected = "Hello World, ThisIsAVeryLongNameForTestingPurposes!";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertEquals(expected, result);
+    }
+
+    @Test
+    @DisplayName("Should return non-null result")
+    void testGetHelloWorld_ReturnsNonNull() {
+        // Arrange
+        String name = "TestUser";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertNotNull(result);
+    }
+
+    @Test
+    @DisplayName("Should start with 'Hello World,'")
+    void testGetHelloWorld_StartsWithHelloWorld() {
+        // Arrange
+        String name = "User";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertTrue(result.startsWith("Hello World,"));
+    }
+
+    @Test
+    @DisplayName("Should end with exclamation mark")
+    void testGetHelloWorld_EndsWithExclamation() {
+        // Arrange
+        String name = "User";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertTrue(result.endsWith("!"));
+    }
+
+    @Test
+    @DisplayName("Should contain the provided name in result")
+    void testGetHelloWorld_ContainsName() {
+        // Arrange
+        String name = "TestUser";
+
+        // Act
+        String result = service.getHelloWorld(name);
+
+        // Assert
+        assertTrue(result.contains(name));
+    }
+}