Issue 526/jdbc with h2 database

.gitignore

@@ -18,3 +18,5 @@ target
 */target
 dependency-reduced-pom.xml
 
+# H2 database files
+*.db

examples/pom.xml

@@ -8,14 +8,9 @@
   <modelVersion>4.0.0</modelVersion>
   <artifactId>examples</artifactId>
   <name>examples</name>
-  <version>1.3.5-SNAPSHOT</version>
+  <version>1.4.0-SNAPSHOT</version>
   <url>https://www.cs.pdx.edu/~whitlock</url>
   <dependencies>
-    <dependency>
-      <groupId>io.github.davidwhitlock.joy</groupId>
-      <artifactId>family</artifactId>
-      <version>1.1.6-SNAPSHOT</version>
-    </dependency>
     <dependency>
       <groupId>io.github.davidwhitlock.joy</groupId>
       <artifactId>projects</artifactId>
@@ -42,6 +37,11 @@
       <version>4.0.5</version>
       <scope>runtime</scope>
     </dependency>
+    <dependency>
+      <groupId>com.h2database</groupId>
+      <artifactId>h2</artifactId>
+      <version>${h2.version}</version>
+    </dependency>
     <dependency>
       <groupId>io.github.davidwhitlock.joy</groupId>
       <artifactId>projects</artifactId>
@@ -50,4 +50,18 @@
       <scope>test</scope>
     </dependency>
   </dependencies>
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.codehaus.mojo</groupId>
+        <artifactId>build-helper-maven-plugin</artifactId>
+        <version>${build-helper-maven-plugin.version}</version>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-failsafe-plugin</artifactId>
+        <version>${surefire.version}</version>
+      </plugin>
+    </plugins>
+  </build>
 </project>

examples/src/it/java/edu/pdx/cs/joy/jdbc/DepartmentDAOIT.java

@@ -0,0 +1,101 @@
+package edu.pdx.cs.joy.jdbc;
+
+import org.junit.jupiter.api.*;
+
+import java.io.File;
+import java.sql.Connection;
+import java.sql.SQLException;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.*;
+
+@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
+public class DepartmentDAOIT {
+
+  private static final String TEST_DEPARTMENT_NAME = "Computer Science";
+  private static int generatedDepartmentId;
+
+  private static String dbFilePath;
+  private Connection connection;
+  private DepartmentDAO departmentDAO;
+
+  @BeforeAll
+  public static void createTable() throws SQLException {
+    // Create database file in temporary directory
+    String tempDir = System.getProperty("java.io.tmpdir");
+    dbFilePath = tempDir + File.separator + "DepartmentDAOIT.db";
+
+    // Connect to the file-based H2 database
+    Connection connection = H2DatabaseHelper.createFileBasedConnection(new File(dbFilePath));
+
+    // Create the departments table
+    DepartmentDAOImpl.createTable(connection);
+
+    connection.close();
+  }
+
+  @BeforeEach
+  public void setUp() throws SQLException {
+    // Connect to the existing database file
+    connection = H2DatabaseHelper.createFileBasedConnection(new File(dbFilePath));
+    departmentDAO = new DepartmentDAOImpl(connection);
+  }
+
+  @AfterEach
+  public void tearDown() throws SQLException {
+    if (connection != null && !connection.isClosed()) {
+      connection.close();
+    }
+  }
+
+  @AfterAll
+  public static void cleanUp() throws SQLException {
+    // Connect one final time to drop the table and clean up
+    Connection connection = H2DatabaseHelper.createFileBasedConnection(new File(dbFilePath));
+    DepartmentDAOImpl.dropTable(connection);
+    connection.close();
+
+    // Delete the database files
+    deleteIfExists(new File(dbFilePath + ".mv.db"));
+    deleteIfExists(new File(dbFilePath + ".trace.db"));
+  }
+
+  private static void deleteIfExists(File file) {
+    if (file.exists()) {
+      assertThat(file.delete(), is(true));
+    }
+  }
+
+  @Test
+  @Order(1)
+  public void testPersistDepartment() throws SQLException {
+    // Create and persist a department (ID will be auto-generated)
+    Department department = new Department(TEST_DEPARTMENT_NAME);
+    departmentDAO.save(department);
+
+    // Store the auto-generated ID for use in subsequent tests
+    generatedDepartmentId = department.getId();
+
+    // Verify that an ID was auto-generated
+    assertThat(generatedDepartmentId, is(greaterThan(0)));
+
+    // Verify the department was saved by fetching it in the same test
+    Department fetchedDepartment = departmentDAO.findById(generatedDepartmentId);
+    assertThat(fetchedDepartment, is(notNullValue()));
+    assertThat(fetchedDepartment.getId(), is(equalTo(generatedDepartmentId)));
+    assertThat(fetchedDepartment.getName(), is(equalTo(TEST_DEPARTMENT_NAME)));
+  }
+
+  @Test
+  @Order(2)
+  public void testFindPersistedDepartment() throws SQLException {
+    // Search for the department that was persisted in the previous test
+    // using the auto-generated ID
+    Department fetchedDepartment = departmentDAO.findById(generatedDepartmentId);
+
+    // Validate that the department persisted between test methods
+    assertThat(fetchedDepartment, is(notNullValue()));
+    assertThat(fetchedDepartment.getId(), is(equalTo(generatedDepartmentId)));
+    assertThat(fetchedDepartment.getName(), is(equalTo(TEST_DEPARTMENT_NAME)));
+  }
+}