This is probably not the best way but it seems to work. The caveat is that it is not the release but the commit method which closes the connection and returns it to the pool, which is quite confusing and could lead to issues if some code "forgets" to commit...
So the client code looks like:
final PostgresConnectionProvider postgres =
new PostgresConnectionProvider("localhost", 5432, params.getDbName(), params.getUser(), params.getPass())
private static DSLContext sql = DSL.using(postgres, SQLDialect.POSTGRES, settings);
//execute some statements here
sql.execute(...);
//and don't forget to commit or the connection will not be returned to the pool
PostgresConnectionProvider p = (PostgresConnectionProvider) sql.configuration().connectionProvider();
p.commit();
And the ConnectionProvider:
public class PostgresConnectionProvider implements ConnectionProvider {
private static final Logger LOG = LoggerFactory.getLogger(PostgresConnectionProvider.class);
private final ThreadLocal<Connection> connections = new ThreadLocal<>();
private final BoneCP pool;
public PostgresConnectionProvider(String serverName, int port, String schema, String user, String password) throws SQLException {
this.pool = new ConnectionPool(getConnectionString(serverName, port, schema), user, password).pool;
}
private String getConnectionString(String serverName, int port, String schema) {
return "jdbc:postgresql://" + serverName + ":" + port + "/" + schema;
}
public void close() {
pool.shutdown();
}
public void commit() {
LOG.debug("Committing transaction in {}", Thread.currentThread());
try {
Connection connection = connections.get();
if (connection != null) {
connection.commit();
connection.close();
connections.set(null);
}
} catch (SQLException ex) {
throw new DataAccessException("Could not commit transaction in postgres pool", ex);
}
}
@Override
public Connection acquire() throws DataAccessException {
LOG.debug("Acquiring connection in {}", Thread.currentThread());
try {
Connection connection = connections.get();
if (connection == null) {
connection = pool.getConnection();
connection.setAutoCommit(false);
connections.set(connection);
}
return connection;
} catch (SQLException ex) {
throw new DataAccessException("Can't acquire connection from postgres pool", ex);
}
}
@Override
//no-op => the connection won't be released until it is commited
public void release(Connection connection) throws DataAccessException {
LOG.debug("Releasing connection in {}", Thread.currentThread());
}
}
