GH-4289: Optimized JdbcChatMemoryRepositoryDialect#from

* Rewrote the method to use `org.springframework.jdbc.support.JdbcUtils#extractDatabaseMetaData`
  for extracting database metadata from the `dataSource`, and obtain the database vendor name
  from the JDBC driver, improving accuracy and robustness.
* Enhanced exception handling: instead of silently ignoring exceptions, it now explicitly reports
  encountered issues, helping users identify problems and select the appropriate dialect more easily;

Fixes #4289

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

@@ -16,15 +16,22 @@
 
 package org.springframework.ai.chat.memory.repository.jdbc;
 
-import java.sql.Connection;
+import java.sql.DatabaseMetaData;
 
 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.
@@ -51,32 +58,29 @@ public interface JdbcChatMemoryRepositoryDialect {
 	 */
 
 	/**
-	 * Detects the dialect from the DataSource or JDBC URL.
+	 * Detects the dialect from the DataSource.
 	 */
 	static JdbcChatMemoryRepositoryDialect from(DataSource dataSource) {
-		// Simple detection (could be improved)
-		try (Connection connection = dataSource.getConnection()) {
-			String url = connection.getMetaData().getURL().toLowerCase();
-			if (url.contains("postgresql")) {
-				return new PostgresChatMemoryRepositoryDialect();
-			}
-			if (url.contains("mysql")) {
-				return new MysqlChatMemoryRepositoryDialect();
-			}
-			if (url.contains("mariadb")) {
-				return new MysqlChatMemoryRepositoryDialect();
-			}
-			if (url.contains("sqlserver")) {
-				return new SqlServerChatMemoryRepositoryDialect();
-			}
-			if (url.contains("hsqldb")) {
-				return new HsqldbChatMemoryRepositoryDialect();
-			}
-			// Add more as needed
+		String productName = null;
+		try {
+			productName = JdbcUtils.extractDatabaseMetaData(dataSource, DatabaseMetaData::getDatabaseProductName);
+		}
+		catch (Exception e) {
+			logger.warn("Due to failure in establishing JDBC connection or parsing metadata, the JDBC database vendor "
+					+ "could not be determined", e);
 		}
-		catch (Exception ignored) {
+		if (productName == null || productName.trim().isEmpty()) {
+			logger.warn("Database product name is null or empty, defaulting to Postgres dialect.");
+			return new PostgresChatMemoryRepositoryDialect();
 		}
-		return new PostgresChatMemoryRepositoryDialect(); // default
+		return switch (productName) {
+			case "PostgreSQL" -> new PostgresChatMemoryRepositoryDialect();
+			case "MySQL", "MariaDB" -> new MysqlChatMemoryRepositoryDialect();
+			case "Microsoft SQL Server" -> new SqlServerChatMemoryRepositoryDialect();
+			case "HSQL Database Engine" -> new HsqldbChatMemoryRepositoryDialect();
+			default -> // Add more as needed
+				new PostgresChatMemoryRepositoryDialect();
+		};
 	}
 
 }