[Solved] How to check if two String are Anagram in Java? Example

Hello guys, if you are preparing for Coding interviews then you already know that String is one of the most popular topics. You will be bound to get some string-based coding problems on interviews. If not, you have come to the right place becuase we'll look at one of the most popular String programming interview questions today,  how to check if two given strings are Anagram of each other? Two String is said to be an anagram of each other, if they contain exactly the same characters but in a different order. For example "ARMY" and "MARY" are an anagram of each other because they contain the exact same characters 'A', 'R', 'M' and  'Y'.

How to create a String or int Array in Java? Example Tutorial

There are several ways to create an array in Java, for example, you can declare the array without initializing it, or you can create and initialize the array in the same line. If you want to make an array with values, then you need to first decide which type of array you want to create? e.g., do you want a String array, which can contain String objects like "abc," "def," or do you want to create an int array that contains int values like 10, 20, etc. In Java, you can create an array of any type, including primitives like byte, int, long, and objects like String, Integer, and other user-defined objects. Let's some code to make a new array in Java.

How to use Map.compute(), computeIfPresent() and ComputeIfAbsent in Java? HashMap and ConcurrentHashMap Example

The JDK 8 has added several useful methods in existing interfaces e.g. java.util.Map, java.util.Collection, and java.util.concurrent.ConcurrentMap. Thanks to default methods, the much-needed evolution of existing interfaces becomes possible. Out of many useful methods, one method which stands out to me is the compute() method, which allows you to update a value in ConcurrentHashMap atomically. As per Java documentation, The compute() function tries to compute a mapping for the specified key and its current mapped value (or null if there is no current mapping). The entire function is performed atomically.

How to use LinkedList in Java? Singly LinkedList and Doubly LinkedList Example Tutorial

Hello friends, we meet again on our journey to Java. I hope you guys are enjoying Java and are trying hands-on too. Today we are gonna discuss a very easy topic (yeah, I mean it :p). But, do not get carried away just by "easy", this is the hottest topic asked in various interviews, exams, and development purposes too. So, what's the wait? Let's start!  As usual, let's start with a scenario. Let's say you want a data structure that stores data in a sequential manner, like an array. But, you don't know the size yet while initializing the data structure. Arrays don't support that, they need a size beforehand. So, what should we do? Do not worry, as Java is here to help us again. Let's explore it then!

How to get First and Last Element of LinkedList in Java [Example]

Hello guys, if you are wondering how to get the first and last element from Java LinkedList then you have come to the right place. Earlier, I have shared the best Data structure and algorithms courses and in today's post, I will teach you how to get the first and last element of a linked list in Java. This is one of the common coding problems but we will see it from different angles. In Java, you don't need to write and create your own LinkedList, there is a built-in class called java.util.LinkedIn and you can use that class whenever you need a linked list data structure. 

Top 30 Spring Core, Spring MVC and Spring Security Interview Questions Answers

Spring Interview Question is one of the first things Java programmers should prepare before appearing on any Java or Spring interview. With the immense popularity of Spring frameworks like Spring MVC and Spring Boot in the Java world, the focus on Spring skills on interviews increases daily. For those who don't know, the Spring framework is one of the most famous structures for Java applications, which aims to simplify Java development. It revolutionized the Java development when it initially came with concepts of  Dependency Injection and Inversion of Control, which made writing a testable and maintainable Java application. 

Difference between Thread.yield and Thread.sleep in Java? Answer

Sleep vs yield in Java

Sleep and yield are two methods that are used to get CPU back from Thread to Thread Scheduler in java but they are completely different than each other. The major difference between Sleep vs yield is that sleep is more reliable than yield and it's advised to use sleep(1) instead of yield to relinquish CPU in multi-threaded Java applications to give an opportunity to other threads to execute. In this Java tutorial, we will what are the differences between yield and sleep in Java. But before seeing the difference between sleep and Yield let's see some similarities between yield and sleep in Java

Top 10 Projects You can Build to Learn Spring Boot in 2024

Hello guys, I have always said that there is no better way to learn anything then actually doing it and its 100% true for Spring Boot, one of the popular Framework for Java application Development. In my 20 years of experience, I have found that the best way to learn Java and Spring Boot is building projects. When you build project, common task surface them like creating a List or sorting a List and then you research and learn. Those learning stuck and make you better developer. Building project also have many advantage like it allows you to use a lot of technologies like Git, IntelliJIDEA, Hibernate, APIs etc together to build something which you can showcase to your potential employer. 

[Solved] java.lang.ClassNotFoundException: org.Springframework.Web.Context.ContextLoaderListener in Java and Spring

Problem : You are getting java.lang.ClassNotFoundException : org.Springframework.Web.
Context.ContextLoaderListener in your Spring-based Java Web application.
Cause: This error comes when you are using the Spring MVC framework in your Java Web application and configured org.springframework.web.context.ContextLoaderListener as a listener in your deployment descriptor also known as web.xml, but the JAR which contains this class is not available in the web application's CLASSPATH.

How to fix org.springframework.beans.factory.BeanCreationException: Error creating bean with name X [Java Spring]

If you are using the Spring framework in your Java application and getting this error during startup it means Spring is not able to initialize the bean X and add it into its application context, Why? There could be multiple reasons like a typo on the spring bean name. Let's take a closer look at the stack trace to find out the real reason:

BeanInstantiationException: Could not instantiate bean class [X]: No default constructor found; nested exception is java.lang.NoSuchMethodException: X.()

Here X is the class, which is declared as Spring bean. The error clearly says that the default constructor is not present in class X.

Difference between Serializable vs Externalizable in Java - Interview Question

What is the difference between Serializable and Externalizable in Java is famous core Java interview questions and for some of them its one of those difficult Java question, which no one wants to see in Java interview. I was in that category until I read Effective Java and explored How Serialization works in Java and find out more about the Serialization process. What makes Serialization questions tricky is, Serialization as a persistence mechanism is not very popular. Many programmers prefer databases, memory-mapped files, or simple text files over Serialization. But Serialization has a distinguished advantage over these mechanisms.

What is the use of DispatcherServlet in Spring MVC? Interview Question Example

Hello guys, In today's article we are going to discuss one interesting and the important Spring MVC concept, which is also a popular Spring Interview question. How DispatcherServlet works internally in Spring MVC or What is the role of DispatcherServlet in Spring MVC are some of the frequently asked Spring MVC Interview Questions. You might have seen them already during your previous Java web development interviews but if you have not, it's a good question to know. In this article, I'll answer these questions by explaining What is DispatcherServlet and its importance in Spring MVC. The DispatcherServlet is one of the important components of the Spring MVC web framework and acts as a Front Controller.

What is @Bean Annotation in Spring Framework? Example Tutorial

Hello Java programmers, if you are wondering what is @Bean annotation in Spring Framework, what is the purpose, and how to use it then you have come to the right place. Earlier, I have shared the best free Spring core and spring MVC courses and In this tutorial, you will learn the most frequently used Spring annotations @Bean, which are used to define different types of beans. Beans are the fundamentals of Spring framework, they represent the POJO class which is created and managed by Spring Framework. Whole Spring framework is about beans and their relationships. 

Top 53 Java Programs for Coding and Programming Interviews

Hello guys, if you are learning to code and programming, or preparing for a programming job interview and looking for some practice material then you have come to the right place. Earlier, I have shared the best string, array, linked list, and binary tree coding problems and In this article, I am going to share some of the most common Java coding and programming problems for beginners. These are the problems, I have solved myself to learn to program and develop a coding sense and these are the ones that keep coming on Java coding interviews. By going through these coding problems you will not only learn Java but also prepare yourself for Java interviews. 

How to Find/Print Leaf nodes in a Binary Tree in Java without Recursion - Example

In the last article, you have learned how to print all leaf nodes of a binary tree in Java by using Recursion, a useful technique to solve binary tree problems and in this article, we'll answer the same question without using Recursion. Why should we do this? Well, it's a typical pattern on a programming job interview to solve the same problem using both Recursion and Iteration. Since some questions are easy to solve using recursion like linked list problems, binary tree-based problems, tower of Hanoi, or Fibonacci series but their non-recursive solution is comparatively tricky, the interviewer tests candidates against this shift in the algorithm.

How to delete multiple elements from a LinkedList in Java? SubList() Example

Hello guys, if you are looking for an easy way to remove a sub set of elements from a LinkedList in Java then you have come to the right place. In the past, I have shown you how to sort a LinkedList in Java and how to create your own linked list implementation in Java and in this article, I am going to introduce you with an interesting method which can be used to delete a portion of LinkedList in Java in shot. Yes, there is a method exists  but not many Java developer knows about it. The method is called subList() and you can use this method with clear method in Java to delete a portion of linked list in one shot.

What is TreeMap in Java? HashMap vs TreeMap Example Tutorial

Hello guys, I hope you all are doing well and having lots of fun reading and learning Java Collections together. Today we are here a meet again on our journey of Java. I hope you all have seatbelts buckled up as today it's gonna be an adventurous ride while learning something that is most used in many production applications, coding, and whatnot. Today's topic, TreeMap in Java is very important because it holds a very significant feature Java development kit provides. This is also one class which many Java developer doesn't pay attention but it is really used for many use cases. Most Java developer just keep their attention to ArrayList, HashSet, and HashMap and thus missing out on many cool Java collection classes like TreeMap, WeakHashMap, and LinkedHashMap which saw earlier.

How ThreadLocal variables works in Java? Explained

Hello guys, ThreadLocal variable is an interesting concept and class from Java API. Not many developer knows about it and very few know how to use it correctly. A couple of years ago it was also a popular Java interview questions for experienced developer but over the years, it lost the popularity as more and more people are now asking about Phaser, CompletableFuture, ForkJoinPool, and other newly added concurrency utilities. ThreadLocal variables, as name suggests is local to thread, which means every thread has there own copy. This means they don't need to look at the main memory when they want to use that variable and best thing is that the variable is not even shared between threads so no locking or synchronization is needed. 

Difference between JIT and JVM in Java? Answered

The main difference between JIT and JVM is that JIT is part of JVM itself and its main function is to improve the performance of JVM by directly compiling some hot code (code that executes above a certain threshold) into native instruction. JIT stands for Just In time compilation and JVM stands for Java Virtual Machine. JVM is a virtual machine used in Java programming platforms to execute or run Java programs. The main advantage of JVM is that JVM  makes Java platform-independent by executing bytecodes. Java source code is compiled into class files, which contain bytecode.

Top 10 Google Cloud Certifications You can Aim in 2024 - Best of Lot

Hello guys, If you are aiming for Cloud Certifications in 2024 then Google Cloud Platform is one of the most in-demand platforms to go for. It's backed by Google and there is a huge demand for people who know Google Cloud Platform or have some experience in using Google Cloud Platform for DevOps, Machine Learning, and Big Data. Getting certified is a good way to learn both essential skills and get recognition and that's why I am sharing the 10 best Google Cloud computing certifications you can aim for in 2024.