ArrayList class is a resizable array, present in java.util package. The difference between an array and an ArrayList in Java, is that the size of an array cannot be modified (i.e. if you want to append/add or remove element(s) to/from an array, you have to create a new array. However, elements can be added/appended or removed from an ArrayList without the need to create a new array.
Hashset class present in java.util package is used to create a collection that uses a hash table for storing data items. HashSet stores the elements by using a hashing mechanism.HashSet contains unique elements only and alows null value. HashSet does not maintain the insertion order and the elements are inserted on the basis of their hashcode. HashSet is the best approach for search operations.
In order to convert a HashSet to Arraylist, we need is to use ArrayList constructor and pass the HashSet instance as a constructor argument. It will copy all elements from HashSet to the newly created ArrayList.
Elements of flower Arraylist are : [marie-gold, rose, tulip, orchid] Element at index 0 is : marie-gold
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