- * Meta JDBC driver that works as redirector/router. It loads SQL-DK's configuration file and - * instantiates a real JDBC connection (PostgreSQL, MariDB etc.) of given name. - *
- * - *
- * Raison d'être: user can define his/her database connections just once (in SQL-DK's configuration)
- * and use them in many other programs – there is no need to define the connection (hostname,
- * username, password, properties…) in each application again and again. User will simply connect to
- * e.g. jdbc:sql-dk://my-connection and this driver reads parameters of
- * my-connection from SQL-DK's configuration and returns real driver implementation.
- *
- * Of course, the real JDBC driver for given database is still needed on the class path. - *
- * - *- * TODO: current version is quite heavy-weight, because it includes whole SQL-DK source tree. Some - * refactoring and separation is desired to provide more light-weight JDBC driver. However the - * public interface and behavior of this driver should remain unchanged. - *
- * - * @author Ing. František Kučera (frantovo.cz) - */ -public class Driver implements java.sql.Driver { - - private static final Logger log = Logger.getLogger(Driver.class.getName()); - - private final Loader loader = new Loader(); - - static { - try { - DriverManager.registerDriver(new Driver()); - } catch (SQLException e) { - log.log(Level.SEVERE, "Unable to register JDBC driver", e); - } - } - - @Override - public Connection connect(String url, java.util.Properties info) throws SQLException { - if (acceptsURL(url)) { - log.log(Level.FINER, "Loading SQL-DK configuration for URL: {0}", url); - String name = extractDatabaseName(url); - log.log(Level.FINE, "Loading SQL-DK configuration for name: {0}", name); - - try { - return getConnection(name, info); - } catch (ConfigurationException e) { - log.log(Level.SEVERE, "Unable to load SQL-DK configuration for name: {0}. Is it defined in {1}?", new Object[]{name, Constants.CONFIG_FILE}); - throw new SQLException("Unable to load SQL-DK configuration for name: " + name, e); - } - } else { - // The driver should return "null" if it realizes it is the wrong kind of driver to connect to the given URL. - return null; - } - } - - private Connection getConnection(String connectionName, java.util.Properties info) throws SQLException, ConfigurationException { - Configuration c = loader.loadConfiguration(); - DatabaseDefinition dd = c.getDatabase(connectionName); - - if (acceptsURL(dd.getUrl())) { - log.log(Level.SEVERE, "SQL-DK meta JDBC driver loops to itself: {0} → {1} Please check {2}", new Object[]{connectionName, dd.getUrl(), Constants.CONFIG_FILE}); - throw new ConfigurationException("SQL-DK meta JDBC driver loops to itself."); - } else { - return Loader.jdbcConnect(dd, translate(info)); - } - } - - private String extractDatabaseName(String url) { - return url.split("//", 2)[1]; - } - - /** - * TODO: refactor/move, reuse - * - * @param info - * @return - */ - private Properties translate(java.util.Properties info) { - Properties properties = new Properties(); - - for (String name : info.stringPropertyNames()) { - String value = info.getProperty(name); - properties.add(new Property(name, value)); - } - - return properties; - } - - @Override - public boolean acceptsURL(String url) throws SQLException { - return url != null && url.startsWith("jdbc:sql-dk://"); - } - - @Override - public DriverPropertyInfo[] getPropertyInfo(String url, java.util.Properties info) throws SQLException { - return new DriverPropertyInfo[0]; - } - - @Override - public int getMajorVersion() { - return 0; - } - - @Override - public int getMinorVersion() { - return 1; - } - - @Override - public boolean jdbcCompliant() { - return false; - } - - @Override - public Logger getParentLogger() throws SQLFeatureNotSupportedException { - throw new SQLFeatureNotSupportedException("Not supported yet."); - } - -}