When working with strings in Java, it is essential to check if a string is null or empty. A null string refers to the absence of any value, while an empty string is a string with zero characters. Failing to handle null or empty strings appropriately can lead to unexpected errors and undesired behavior in…
Read More Check if String is Null or Empty in JavaFinding the maximum and minimum values in an array is a common requirement in various programming scenarios. It allows you to extract key insights from your data, such as identifying the highest and lowest values, or determining the range of values present. This knowledge can be utilized in numerous applications, including statistical analysis, data processing,…
Read More Finding Max and Min Values in a Java ArrayJSON (JavaScript Object Notation) is a lightweight data-interchange format that has gained significant popularity in modern web development. It provides a simple and human-readable way to represent structured data. JSON consists of key-value pairs and supports various data types, including strings, numbers, booleans, arrays, and nested objects. The importance of JSON lies in its ability…
Read More Convert Java Objects to JSONThe java.lang.UnsupportedClassVersionError is a runtime error in Java that occurs when a Java Virtual Machine (JVM) encounters a class file with a version that is not supported by the JVM. This error typically arises when there is a mismatch between the version of the JVM executing the code and the version in which the class…
Read More How to Resolve java.lang.UnsupportedClassVersionError?Java is a powerful and versatile programming language that can be used to create various types of applications. However, like any other software, Java applications may encounter problems such as errors, exceptions, memory leaks, performance issues, etc. Troubleshooting Java applications can be challenging and time-consuming, especially if you don’t have the right tools and techniques.…
Read More Troubleshooting Java ApplicationsTesting is an essential skill for any Java developer. It helps you ensure the quality and reliability of your code, as well as find and fix bugs faster. On this page, you will find a collection of tutorials that will teach you how to test Java code using JUnit 5 and Mockito. JUnit 5 is…
Read More Testing Java CodeWelcome to your comprehensive hub for Java interview preparation. This page is your one-stop shop, designed to support Java developers at all stages of their careers, from those just starting out to seasoned professionals. You’ll find carefully curated sets of interview questions tailored to your level of expertise – be it junior, intermediate, or advanced.…
Read More Java Interview QuestionsWelcome 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 ExamplesIn 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 JavaIn Java 12 and Java 13, Switch Expressions were added as preview features, and in Java 14 they became a standard feature. The Switch Expressions feature extends regular Java switch statements and can be used as either a statement or an expression. The entire switch block evaluates to a value that can then be assigned…
Read More Java Switch ExpressionsOutput: true true true As you can see, the Car class inherits the Vehicle class, which is itself an instance of the Object class. Similarly, the Car class is an instance of both the Vehicle and the Object class. In Java, all classes inherit some useful methods from the Object class, which we will discuss…
Read More Object Class in JavaReversing a string is a common task in Java programming, and there are several ways to accomplish this. In this tutorial, we’ll explore four different methods for reversing a string in Java, using the StringBuilder class, the for loop, recursion, and a character array. We’ll provide examples of each method and explain how they work.…
Read More Reverse a String in Javapublic int sum(int a, int b, int c) { // body of the method } class Printer { // fields public void printBook(String bookName) { // … } public void printBook(String bookName, int numberOfPages) { // … } } class Printer { // fields public void printBook(String bookName) { // … } public String printBook(String…
Read More Method Overloading in Java