List in Java
There is a List interface in Java which is a child interface of Collection. The List interface supports access, insertion, deletion of the elements. Each element in List has its own index, starting at 0, then 1 and so on. To create List objects we have ArrayList() LinkedList() Vector() and Stack()
HashMap in Java
In Java, HashMap is a Map based collection class that is used for storing Key and value pairs which is denoted as HashMap. It does not maintain order of elements, allows one null key, multiple null values, is not thread safe, default size is 16, default load factor is 0.75 JDK1.7, JDK1.8
Java Collections Framework: ArrayList
Java ArrayList is one of the most widely used Collection class. java.util.ArrayList class implements java.util.List interface. Java ArrayList also implements RandomAccess, Cloneable and Serializable interfaces. Java ArrayList class extends AbstractList class that the skeleton implementation of list
Java Collections Framework: Iterable Interface
The Iterable interface (java.lang.Iterable) is the root interface of the Java collection classes. The Collection interface extends Iterable interface, so all subtypes of Collection implement the Iterable interface. This interface is to represent structures whose value can be traversed one by one.
Java Collections Framework: Collection Interface
The Collection interface (java.util.Collection) is one of the root interfaces of the Java collection classes. A collection represents a group of objects known as its elements. The following 6 interfaces extends the Collection interface List, Set, SortedSet, NavigableSet, Queue, and Deque.