fix: Fix UT

Signed-off-by: Sun Yuhan <[email protected]>

Author: sunyuhan1998

memory/repository/spring-ai-model-chat-memory-repository-jdbc/src/main/java/org/springframework/ai/chat/memory/repository/jdbc/JdbcChatMemoryRepositoryDialect.java

@@ -20,13 +20,18 @@
 
 import javax.sql.DataSource;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import org.springframework.jdbc.support.JdbcUtils;
 
 /**
  * Abstraction for database-specific SQL for chat memory repository.
  */
 public interface JdbcChatMemoryRepositoryDialect {
 
+	Logger logger = LoggerFactory.getLogger(JdbcChatMemoryRepositoryDialect.class);
+
 	/**
 	 * Returns the SQL to fetch messages for a conversation, ordered by timestamp, with
 	 * limit.
@@ -56,12 +61,17 @@ public interface JdbcChatMemoryRepositoryDialect {
 	 * Detects the dialect from the DataSource.
 	 */
 	static JdbcChatMemoryRepositoryDialect from(DataSource dataSource) {
-		String productName;
+		String productName = null;
 		try {
 			productName = JdbcUtils.extractDatabaseMetaData(dataSource, DatabaseMetaData::getDatabaseProductName);
 		}
 		catch (Exception e) {
-			throw new RuntimeException("Failed to obtain JDBC product name or establish JDBC connection", e);
+			logger.warn("Due to failure in establishing JDBC connection or parsing metadata, the JDBC database vendor "
+					+ "could not be determined", e);
+		}
+		if (productName == null || productName.trim().isEmpty()) {
+			logger.warn("Database product name is null or empty, defaulting to Postgres dialect.");
+			return new PostgresChatMemoryRepositoryDialect();
 		}
 		return switch (productName) {
 			case "PostgreSQL" -> new PostgresChatMemoryRepositoryDialect();