Core java

1. Introduction Java 8 has introduced a new feature called Lambda expressions. This is considered to be major change for Java because it introduces a way of programming that is more about actions than the details of how things are done. Other languages such as Scala already have this feature so this is not new […]

1. Introduction In this post, We will introduce default methods in interface which are introduced in Java 8. Have you ever encountered a situation where you created an interface and several classes implemented it? Now, suppose you need to add new methods to the interface. Doing so would lead to a multitude of compilation errors across […]

Some of the popular interview questions are “What are differences between abstract class and interface“. “When will you use abstract class and when will you use interface“. So in this article ,we will go through this topic. Before going through differences between them, Lets go through its introduction. Abstract class Abstract classes are created to […]

In this post, we will see  how you can use comparable to sort list of objects in java. Comparable interface: Class whose objects to be sorted must implement this interface.In this,we have to implement compareTo(Object) method. For example: [crayon-6a1de2090774c682142202/] If any class implements comparable inteface then collection of that object can be sorted automatically using […]

If two or more methods have same name , but different argument then it is called method overloading. Why you would do that (same name but different argument)? Lets take an example. You want to print salary of employee and sometimes company gives bonus to their employee and sometimes it don’t.So If company don’t give […]

In this post, we will see how you can use comparator to sort list of objects in java. Comparator: When you want to sort the list of objects of a class,you can use Comparator interface. You don’t need to implement Comparator on the class whose objects need to be sorted. You can create a separate […]

If subclass is having same method as base class then it is known as method overriding Or in another words, If subclass provides specific implementation to any method which is present in its one of parents classes then it is known as method overriding Lets start with a real time example: In a small organization,There […]

This is 3rd part of java Serialization tutorial Java Serialization Tutorial: Serialization in java Java Serialization interview questions and answers serialversionuid in java serializationexternalizable in java Transient keyword in java Difference between Serializable and Externalizable in Java Before understanding Externalizable interface, you need to have idea about Serialization.You can read more about Serialization at Serialization […]

Java HashMap: HashMap in java How HashMap works in java hash and indexfor method in HashMap hashcode and equals method in java How to sort HashMap by keys and values Difference between HashMap and HashSet Difference between HashMap and Hashtable How to iterate over HashMap Target AudienceThis post is for the people who already have […]