NullPointerException is a common runtime exception in Java that occurs when you attempt to access or invoke a method on a null object reference. In simpler terms, it signifies an attempt to use an object that has not been initialized or has been set to null. When the JVM encounters a null reference, it throws…
Read More How to Resolve the “NullPointerException” Error?When working with Java applications, encountering the error message “Could not find or load main class” can be quite perplexing. This error typically occurs when the Java Virtual Machine (JVM) is unable to locate or load the specified main class during the execution of a Java program. The main class serves as the entry point…
Read More How to Resolve the “Could not find or load main class” Error?The java.lang.NoClassDefFoundError is a common runtime error encountered by Java developers. It indicates that the Java Virtual Machine (JVM) or the ClassLoader is unable to find the definition of a class at runtime, despite the class being present during compilation. This error typically occurs when a class that your program depends on is missing during…
Read More How to Resolve java.lang.NoClassDefFoundError?Java, a popular programming language, relies on the JVM to execute Java bytecode. The JVM provides a managed runtime environment that handles memory allocation and garbage collection, among other tasks. However, even with the JVM’s memory management capabilities, developers may encounter Out-of-Memory Errors when their applications consume more memory than the JVM can provide. Understanding…
Read More Java: Out-of-Memory Errors in the JVMThis page serves as a comprehensive resource for job seekers looking to excel in Java programming interviews. Building upon the success of our previous guide, Part 2 delves deeper into the realm of Java by focusing on essential programs related to string manipulation and sorting algorithms. Make sure to visit Part 1 of this series…
Read More Top Java Programs and How to Solve Them: Job Interview Guide (Part 2)The Java programming language is widely used in various industries, ranging from software development and web applications to mobile app development and enterprise solutions. Consequently, employers place great importance on assessing candidates’ Java skills during the interview process. Preparing for a Java interview goes beyond brushing up on technical knowledge. It involves understanding the interview…
Read More How to Prepare for Java Interview: Expert Tips and Preparation StrategiesThroughout this page, we will explore a curated collection of top Java programs commonly encountered in job interviews. Whether you are a beginner looking to enhance your Java skills or an experienced developer preparing for technical interviews, these Java programs will serve as an excellent resource to strengthen your understanding of core programming concepts and…
Read More Top Java Programs and How to Solve Them: Job Interview Guide (Part 1)In this page, I aim to provide valuable insights for anyone looking to excel in their next Java job interview. We will explore some of the most popular Java interview questions related to programming concepts such as Object-Oriented Programming (OOP), the Collections Framework, Threads and more. You might also be interested to check the following…
Read More Most Popular Java Interview QuestionsFor senior developers, having a firm grasp of advanced Java programming concepts and being well-prepared for job interviews are crucial. In this page, we will explore some of the most captivating interview questions that senior developers are likely to come across during their job search. You might also be interested to check the following collections…
Read More Java Interview Questions for Senior DevelopersBeing well-prepared for job interviews and having a strong grasp of fundamental Java programming concepts are essential for intermediate developers. In this page, we will delve into some of the most intriguing interview questions that intermediate developers are likely to encounter in their job search. You might also be interested to check the following collections…
Read More Java Interview Questions for Intermediate DevelopersWelcome to this tutorial on string formatting in Java. String formatting, in simple terms, is the method of adding or altering content within a string. We can do this in three ways – using printf(), MessageFormat, and something called the Formatter class. Most Java developers favour the Formatter class, so that’s what we’ll focus on.…
Read More Java String Formatter: A Guide with ExamplesAs a junior developer, it’s important to be prepared for job interviews and have a good understanding of the fundamental concepts of Java programming. In this page, we’ll be exploring some of the most interesting interview questions that junior developers can expect to encounter during their job search. You might also be interested to check…
Read More Java Interview Questions for Junior DevelopersIn this tutorial, we will explore how to ignore unknown JSON fields in Java using Jackson. We will cover the default behaviour, ignoring unknown properties on a class level, ignoring unknown properties globally, and how to deal with incomplete JSON. Additionally, we will discuss security concerns related to ignoring unknown properties using annotations. If you’re…
Read More Ignore Unknown JSON Fields with Java JacksonIn this tutorial, we are going to learn how to convert from our local time to EST/EDT date and time. This is useful in different situations, for example, when you are contacting a colleague in a different timezone or if you are checking out flights. This requires that you convert a date/time from one timezone…
Read More Converting date to EST/EDT Timezone in Javaclass UserIdComparator implements Comparator<User> { public int compare(User user1, User user2) { if (user1.userId == user2.userId) { return 0; } else if (user1.userId > user2.userId) { return 1; } else { return -1; } } } We will now create a UsernameComparator class that establishes the comparison logic based on the username field. This class…
Read More Comparator interface in Java