Java Program that Shows Use of Collection Interface

14 Sep, 2021
The Collection framework is a unified architecture for representing and manipulating collections, enabling collections to be manipulated independently of implementation details.
Uses and advantages of Collection Framework:
This reduces the efforts of programmers by providing data structures and algorithms, so we do not have to write them.
This increases performance by providing a high-performance implementation of data structures and algorithms.
This provides interoperability between unrelated APIs by establishing a common language to pass collections back and forth.
Reduces the effort required to learn APIs by requiring you to learn multiple ad hoc collection APIs.
This provides static methods that perform useful functions on collections, such as sorting a list.
This provides Wrapper implementation which adds functionality, such as synchronization, to other implementations.
And many more advantages it provides for us to use and tackle the problems of development.
Usages: Examples of different types of Interfaces are given below:
List InterfaceLiked ListMap Interface Stacks
List Interface
Liked List
Map Interface 
Stacks
Use Case 1: List Interface
Java
// Java Program that Shows Use of Collection Interface// ArrayList import java.util.*; class GFG {    public static void main(String args[])    {        ArrayList<String> list = new ArrayList<String>();        list.add("Geeks");        list.add("areyou");        list.add("working");        list.add("hard?");         Iterator itr = list.iterator();        while (itr.hasNext()) {            System.out.println(itr.next());        }    }}
Geeks
areyou
working
hard?
Use Case 2: Linked List
Java
// Java Program that Shows Use of Collection Interface// LinkedList import java.util.*; // Class testing java Collectionpublic class GFG {     // Main driver method    public static void main(String args[])    {        // Creating a LinkedList        LinkedList<String> al = new LinkedList<String>();         // Adding elements to above linked list        al.add("Geeks");        al.add("areyou");        al.add("working");        al.add("hard?");         // Iterator        Iterator<String> itr = al.iterator();         // Condition check over elements inside using        // hasNext() method which holds true till there is        // element inside list        while (itr.hasNext()) {             // Printing elements of LinkedList            System.out.println(itr.next());        }    }}
Geeks
areyou
working
hard?
Use Case 3: Map Interface 
Java
// Java Program that Shows Use of Collection Interface// Hash-Map import java.util.*;public class GFG {     // Main driver method    public static void main(String[] args)    {        // Creating a Map        Map<Integer, String> map = new HashMap<>();         // Adding elements to map        map.put(1, "Geeks");        map.put(2, "are");        map.put(3, "you");        map.put(4, "working");         // Traversing Map        // Converting to Set so that traversal is accessed        Set set = map.entrySet();         // Iterator        Iterator itr = set.iterator();         // Condition check over elements inside using        // hasNext() method which holds true till there is        // element inside list         while (itr.hasNext()) {            // Converting to Map.Entry so that we can get            // key and value separately             Map.Entry entry = (Map.Entry)itr.next();             // Printing elements inside HashMap            System.out.println(entry.getKey() + " "                               + entry.getValue());        }    }}
1 Geeks
2 are
3 you
4 working
Use Case 4: Stacks 
Java
// Java Program that Shows Use of Collection Interface// Stack import java.util.*;public class GFG {     // Main driver method    public static void main(String args[])    {        // Creating a stack in memory        Stack<String> stack = new Stack<String>();         // Adding elements to stack        stack.push("Geeks");        stack.push("are");        stack.push("you");        stack.push("working");        stack.push("hard?");         // pop() returns all elements of stack        stack.pop();         //. iterator        Iterator<String> itr = stack.iterator();         // Condition check over elements inside using        // hasNext() method which holds true till there is        // element inside list        while (itr.hasNext()) {             // Print all popped elements            System.out.println(itr.next());        }    }}
Geeks
are
you
working
surinderdawra388
sagartomar9927
simmytarika5
Java-Collections
Picked
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Java Programs
Java
Java-Collections
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