Difference between collection and collections in java

JavaObject Oriented ProgrammingProgramming

Java collection framework is used to manipulate the collection of the object. Collection framework contains multiple wrapper classes , convenience class , classes for legacy implementation like vector and Hashtable, collection interfaces and etc.    

Collection is an interface in the java collection framework. It is divided into two parts −

  • Java util collection - It contains classes such as Set , queue , List and etc.
  • Java util map - It contains classes such as Map , sortedMap and etc.

On the other hand , Collections is the one the utility class. Main purpose of this class is to provide convenience method to the developers. This class has only static methods that operate on and return collection. The methods of this class all throw a NullPointerException if the collections or class objects provided to them are null.

Sr. No.
Key
Collection
Collections

1

Basic 

 It is an interface in Java collection framework 

It is a utility class in Collection framework 

2

Static Methods 

It doesn't has all static methods 

It has all static method 

3

Operation 

It is used to store list of object in a single object  

It is used to operate on collection.

Example of Collection and Collections

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class Main {
   public static void main(String[] args) {
      // List
      List list = new ArrayList();
      list.add("HCL");
      list.add("DELL");
      // Sorting List in ascending order according to the natural ordering
      Collections.sort(list);
      list.forEach(System.out::println);
   }
}
raja
Published on 21-Jan-2020 08:11:22
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