complete tutorials on core java in java

Map is Interface and Hashmap is class that implements that In Java, Map is an interface that represents a collection of key-value pairs, where each key is associated with exactly one value. HashMap is a specific implementation of the Map interface. Here are some key differences between Map and HashMap: Interface vs. Implementation: Map is the interface … Read more

Map is an object that maps keys to values. A map cannot contain duplicate keys: Each key can map to at most one value. This Map permits null value In Java, the Map interface is a part of the Java Collections Framework and is used to represent a collection of key-value pairs where each key must be … Read more

Java Collections Framework provides a set of interfaces and classes that support operations on a collections of objects. The Java Collections API is a set of classes and interfaces in Java that provide a framework for working with collections of objects. A collection is an object that represents a group of objects, known as elements. … Read more

Best practices relating to Java Collection framework are as follow: Choose the right type of data structure based on usage patterns like fixed size or required to grow, duplicates allowed or not, ordering is required to be maintained or not, traversal is forward only or bi-directional, inserts at the end only or any arbitrary position, … Read more

import java.util.ArrayList; import java.util.LinkedHashSet; import java.util.List;   public class CollectionFunction {     public <e> List<e> function (List <e> list) {           return new ArrayList<e>(new LinkedHashSet<e>(list));     } } The above code removes duplicates from a supplied list by passing it through an implementation of a Set interface. In this case, a LinkedHashSet is used to … Read more