private void open() {
try {
conn = JdbcUtils.getConnection(driver, url, user, password);
} catch (SQLException e) {
throw DbException.convert(e);
}
}
/**
* Closes the connection if this is the last link to it.
*
* @param force if the connection needs to be closed even if it is still used elsewhere (for
* example, because the connection is broken)
*/
synchronized void close(boolean force) {
if (--useCounter <= 0 || force) {
JdbcUtils.closeSilently(conn);
synchronized (map) {
map.remove(this);
}
}
}