Arraylist to Array Using ToArray() in java

Arraylist to Array Using ToArray() in java

Syntax: <T> T[] toArray(T[] a)

Eg : String[] y = x.toArray(new String[0]);

T – the runtime type of the array to contain the collection
Parameters:
a – the array into which the elements of this list are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose.
Returns:
an array containing the elements of this list
Throws:
ArrayStoreException – if the runtime type of the specified array is not a supertype of the runtime type of every element in this list
NullPointerException – if the specified array is null

Returns an array containing all of the elements in this list in proper sequence (from first to last element); the runtime type of the returned array is that of the specified array.

Size of Array created is equal to size of ArrayList:

If the list fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this list.

Size of Array created is not equal to size of ArrayList:
If the array has more elements than the list, the element in the array immediately following the end of the list is set to null.

Like the toArray() method, this method acts as bridge between array-based and collection-based APIs. Further, this method allows precise control over the runtime type of the output array, and may, under certain circumstances, be used to save allocation costs.

Note that toArray(new Object[0]) is identical in function to toArray().

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