Core java

Learn about how to format Instant to String in java.

This tutorial provides the top 20 java projects for beginners for practice. These projects will help you to learn java quickly and efficiently.

Learn about how to convert Roman number to Integer in java.

Learn about how to declare String array in java.

Learn about how to create deep copy of ArrayList in different ways.

Learn about how to solve Variable might not have been initialized in Java.

In this article, we look at a problem : Given an Array of Positive Integers, Find the [Maximum Difference](https://java2blog.com/maximum-difference-between-two-elements-in-array/ "Maximum Difference") between Two Adjacent Numbers. For each pair of elements we need to compute their difference and find the Maximum value of all the differences in array. Let us look at an example, Consider this […]

In this tutorial, we will see the most frequent java exception i.e. Exception in thread main java.lang.NullPointerException. It is one of the Runtime Exception. Raise your hand if you ever got NullPointerException while working on java code. I am sure that this is the exception you might have encountered most frequently. You might also agree […]

In this article, we will look at a problem: Given an Input String and a Character, we have to Count Occurrences Of character in String. [toc] For Example, If the Given String is : "Java2Blog" and we have to count the occurrences of Character ‘a’ in the String. Therefore, Count of 'a' is : 2 […]