How to handle JDBC Dao exceptions

/* First define a DaO exception, inherited from runtimeexception. The reason for inheriting runtimeexception is that the business layer can be free to choose whether to handle exceptions and do not need to declare an exception in the interface to avoid interface pollution. */Class daoexception extends runtimeexception {//...} // define Dao interface Dao {void create (po); PO Research (Object poid); void Update (po); void Delete (po );} // implement the DaO Interface Class daoimpl implements Dao {void create (po ){//... try {//...} catch (sqlexception e) {// throw a repackaging exception throw new daoexception (E. getmessage, e );}//...} //...}