After deleting multiple entries the id field (auto_increment) does not reset creating non sequential id numbers.

Fix
Edit the public int deleteAddress method inside AddressesDB.java by inserting...

String alter_increment ="alter table addresses auto_increment=1";

and by adding inside the try block

Statement stmt= this.connection.createStatement();
stmt.execute(alter_increment);

**before realeasing the connection this.releaseConnection ();**

use ant to remove and install the application again.