强制例外

Question

Set cust = customer.getCustomerBills();
Iterator<Customer> seriter = (Iterator)cust;

I am facing a casting exception when I iterate on Set.

Exception is: org.hibernate.collection.PersistentSet cannot be cast to java.util.Iterator . What am I doing wrong?

Answer 1

You don't cast a collection to Iterator . You obtain one: cust.iterator() :

Set<Customer> cust = customer.getCustomerBills();
Iterator<Customer> seriter = cust.iterator();

(A Collection is Iterable , which defines the iterator() method.)

Answer 2

Iterator seriter = (Iterator)cust; is not a proper casting so an exception is being thrown.

use Iterator seriter = cust.iterator();