Add missing test

Signed-off-by: Tomoyuki Morita <[email protected]>

spark/src/test/java/org/opensearch/sql/spark/helper/FlintHelperTest.java

@@ -0,0 +1,45 @@
+package org.opensearch.sql.spark.helper;
+
+import static org.opensearch.sql.spark.data.constants.SparkConstants.FLINT_DEFAULT_AUTH;
+import static org.opensearch.sql.spark.data.constants.SparkConstants.FLINT_DEFAULT_HOST;
+import static org.opensearch.sql.spark.data.constants.SparkConstants.FLINT_DEFAULT_PORT;
+import static org.opensearch.sql.spark.data.constants.SparkConstants.FLINT_DEFAULT_REGION;
+import static org.opensearch.sql.spark.data.constants.SparkConstants.FLINT_DEFAULT_SCHEME;
+import static org.opensearch.sql.spark.data.constants.SparkConstants.FLINT_INTEGRATION_JAR;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+class FlintHelperTest {
+
+  private static final String JAR = "JAR";
+  private static final String HOST = "HOST";
+  private static final String PORT = "PORT";
+  private static final String SCHEME = "SCHEME";
+  private static final String AUTH = "AUTH";
+  private static final String REGION = "REGION";
+
+  @Test
+  public void testConstructorWithNull() {
+    FlintHelper helper = new FlintHelper(null, null, null, null, null, null);
+
+    Assertions.assertEquals(FLINT_INTEGRATION_JAR, helper.getFlintIntegrationJar());
+    Assertions.assertEquals(FLINT_DEFAULT_HOST, helper.getFlintHost());
+    Assertions.assertEquals(FLINT_DEFAULT_PORT, helper.getFlintPort());
+    Assertions.assertEquals(FLINT_DEFAULT_SCHEME, helper.getFlintScheme());
+    Assertions.assertEquals(FLINT_DEFAULT_AUTH, helper.getFlintAuth());
+    Assertions.assertEquals(FLINT_DEFAULT_REGION, helper.getFlintRegion());
+  }
+
+  @Test
+  public void testConstructor() {
+    FlintHelper helper = new FlintHelper(JAR, HOST, PORT, SCHEME, AUTH, REGION);
+
+    Assertions.assertEquals(JAR, helper.getFlintIntegrationJar());
+    Assertions.assertEquals(HOST, helper.getFlintHost());
+    Assertions.assertEquals(PORT, helper.getFlintPort());
+    Assertions.assertEquals(SCHEME, helper.getFlintScheme());
+    Assertions.assertEquals(AUTH, helper.getFlintAuth());
+    Assertions.assertEquals(REGION, helper.getFlintRegion());
+  }
+}