有人可以帮我理解 object[] toArray 吗？

Question

toArray() -- this method returns a newly allocated array containing the elements in the multiset. The array this method returns must only contain the elements in the multiset and not any nulls or other values that are stored in the backing store, but are not in the multiset.

considering _store is the array in whicch the elements are stored. I really dont understand the concept of what exactly I'm supposed to do! I have to complete the method

Answer 1

Data structures are usually traversed using Iterator , but sometimes, they might be required as arrays. So, toArray() method basically provides the contents of the data structure in the form of the array. Return type is Object[] so that any object can be returned through it. Explicit type cast is required to obtain the real object.

Note: This method must allocate a new array. It means that although the contents of the array and data structure are same, but the actual object references are different. So that, if someone modified the element in data structure, it does not affect the array.