Is "Java Concurrency in Practice" still Valid in the Era of Java 21?

Hello guys, one of my reader Shobhit asked this question on my blog post about 12 must-reads advanced Java books for intermediate programmers - part 1. I really like the question and thought that many Java programmers might have the same doubt whenever someone recommends them to read Java Concurrency in Practice. When this book came first in 2006, Java world was still not sure of about new concurrency changes made in Java 1.5, I think the first big attempt to improve Java's built-in support for multi-threading and concurrency. Many Java programmers were even not aware of new tools introduced in the API like CountDownLatch, CyclicBarrier, ConcurrentHashMap, and much more. The book offered them the seamless introduction of those tools and how they can use them to write high-performance concurrent Java applications.

Difference between @Component, @Service, @Controller, and @Repository in Spring

Before you learn the difference between @Component, @Service, @Controller, and @Repository annotations in the Spring framework, it's important to understand the role of @Component annotation in Spring. During the initial release of Spring, all beans are used to be declared in an XML file. For a large project, this quickly becomes a massive task, and Spring guys recognize the problem rather quickly. In later versions, they provide annotation-based dependency injection and Java-based configuration. From Spring 2.5 annotation-based dependency injection was introduced, which automatically scans and registers classes as Spring bean which is annotated using @Component annotation.

Top 20 Spring Framework Annotations Java Developers Should Know

Hello guys, annotations are quite important when working in modern Java application as almost all frameworks and libraries nowadays use annotations, including Spring Framework. There was time when we need to remember classes and methods to make effective use of JDK or any open source library but now we also need to remember annotations. For example, to use JUnit you must know about annotations like @Test, @BeforeEach, @AfterEach, @Disabled and so on. Similarly for Spring framework you need to know annotations like @Configuration, @Bean, @Component, @Service, @Value, @Autowired, @Repository, @Qualifier, @Required and more. 

Top 10 Java and Web Development Courses from Udemy in 2024 - Best of Lot

Hello guys, I am sure you all have made your goals and resolutions for this year, like what to learn in 2024. If you haven't, then check out my post 10 Things Java programmers should learn in 2024 for some ideas. If you have already made your goal, then it is time to think about how you are going to achieve them. For example, my top 5 goals in 2024 are to learn Java 17, AWS, Microservices, Spring 5, and Spring Security 5, but how am I going to learn them? Well, I like books and online courses, and that's why I have been searching for some excellent courses on Java, Spring Boot, Microservices, Docker, Web development, and Spring. 

Top 17 Spring AOP (Aspect-Oriented Programming) Interview Questions Answers

If you are preparing for Java and Spring Developer interviews or Spring professional certification then a good knowledge of Aspect-oriented Programming or AOP is required. It's a boring and tough topic but important from a Spring interview and Spring certification point of view and that's where these 15+ AOP interview questions come really handy. You can use them to revise key AOP concepts before any telephonic or face-to-face interview as well as to learn and explore more about Aspect-Oriented Programming. In this article, I am going to share frequently asked AOP interview questions and also tried to answer AOP questions give on the official Spring certification exam guide.

20 Design Patterns and Software Design Interview Questions for Programmers

Design patterns and software design questions are an essential part of any programming interview, no matter whether you are going for a Java interview or a C#  interview. In fact, programming and design skills complement each other quite well, people who are good programmers are often good designers as well as they know how to break a problem in to piece of code or software design but these skills just don’t come. You need to keep designing, programming both small-scale and large-scale systems, and keep learning from mistakes. 

Top 5 Spring Boot Features for Java Development

You might have heard about Spring Boot and its magical powers about creating a Spring Web application in just under 140 characters which can be written in a tweet, but what does that really mean? What are those features which provide Spring Boot such power and make Spring application development so easy? Well, that's what you will learn in this article, but if you are in hurry let me tell you that you will learn about Spring Boot's auto-configuration, Starter dependencies, Spring Boot CLI, Actuator, and Spring Initializer feature in detail. These are the feature that takes away most of the pain and friction associated with writing a Spring-based Java web application.

What is bean scope in Spring Framework? Example Tutorial

Java classes or POJO which are managed by Spring Framework are called Bean or Spring Beans and Bean scope in Spring framework or Spring MVC is scope for a bean managed by Spring IOC container. Bean scope refers to the lifecycle and visibility of a bean instance in spring container. The scope determines how long the bean instance will live and how it will be shared with the other parts of application. You may know that Spring is a framework that is based on Dependency Injection and Inversion of Control and provides bean management facilities to Java application. In Spring-managed environment bean (Java Classes) are created and wired by the Spring framework. Spring allows you to define how those beans will be created and the scope of the bean is one of those details. Scope are similar to access modifiers in Java which specifies visibility of a particular class. 

Difference between @RequestMapping and @GetMapping in Spring MVC? Example

Hello Java programmers, if you are wondering what is the difference between @RequestMapping and @GetMapping annotation in Spring MVC and when and how to use them then you have come to the right place. Earlier, I have shared the best Spring MVC courses and books, and In this tutorial, we are going to discuss about Spring MVC and spring boot web services. In there, most of the interviewers asked about the difference between @RequestMapping and @GetMapping annotations in spring applications. Before going to discuss the difference between these annotations, first, understand what is @RequestMapping?, How do we use the @RequestMapping?, What is a request? and types of them.

Spring Boot @Transactional Annotation Example - How to Manage Transactions using Spring Framework?

One of the most essential parts of Spring MVC is the @Transactional annotation, which provides support for transaction management and allows developers to concentrate on coding business logic rather than worrying about data integrity in the event of system failures. In other words, @Transactional annotation  simplifies the process of transaction management and it allows you to specify transactional behavior directly within your code, typically at the service layer. You can put @Transactional annotation both at the class level and method level. When you put the @Transacational at the class level, it applies to all the public method of the class but when you put the @Transacational annotation at the method level. It only applies to that method. 

4 Ways to take Heap dump in Tomcat and Java and 3 Tools to Analyse .hprof files

The heap dump is a great source of information on identifying memory related issues on Java application e.g. web and application servers like Tomcat, WebLogic, JBoss, WebSphere and IDEs like IntelliJIDEA and Eclipse. When you take heap dump all live objects of heap with their count and other details are written into a huge file (the .hprof file) for analysis. The name and location of heap dump file is provided by command you use to take the heap dump. There are many command line tools in JDK e.g. jmap and jcmd which can be used to take the heap dump in Java. 

Top 50 Java 8 Stream, Lambda, and Functional Programming Interview Questions

Hello guys, if you are preparing for Java interviews and looking for some Java 8 Stream, Lambda Expression, and other Java 8 features then you have come to the right place. Earlier, I have shared 140+ Core Java interview questions, 50 Java Programs from Interviews,  and 20+ Spring Boot questions and in this article, I am going to share Stream, Lambda expression, and other Java 8 feature-based questions.  Java 8 features are now not remained as good to know features. They have been increasingly adopted by many organizations and most of the new development encourage developers to write code in Java 8 style to take full advantage of massive CPU power available in modern servers like HP 380 Gen 8 servers, also known as G8. 

Top 3 Design Patterns and Best Practices Java Developers Can Learn From Spring Framework

There is no doubt that the Spring Framework is one of the most popular Java frameworks and makes it really easy to create real-world, enterprise-grade Java applications easy by providing features like dependency injection and inversion of control. But, to be honest, Spring is much more than just another DI and IOC framework. It goes one more level to simplify many Java APIs like JDBC, JMS, Java Mail, etc by providing a useful layer of abstraction. It's much more comfortable to work with JDBC with Spring's JdbcTempalte and other utility classes. They remove most of the friction Java developer faces with respect to executing SQL statements and processing ResultSet to get the Java object they want.

2 Reasons of org.springframework.beans.factory.BeanCreationException: Error creating bean with name [Solution]

The Spring framework is one of the most popular frameworks for developing Java applications. Apart from many goodies, it also provides a DI and IOC container that initializes objects and their dependencies and assembles them together. The Java classes created and maintained by Spring are called Spring bean. At the startup, when the Spring framework initializes the system by creating objects and their dependencies depending upon @Autowired annotation or spring configuration XML file, it throws "org.springframework.beans.factory.BeanCreationException: Error creating a bean with name X" error if it is not able to instantiate a particular Spring bean.

Top 21 Spring Framework and Spring Boot Testing Interview Questions Answers for 2 to 5 Years Experienced

Testing is an important part of Software development but many people don't pay attention to it only to find bugs in the later stages of development that can be easily avoided by unit testing. When it comes to Java and Spring Boot development, we are lucky to have JUnit, Mockito, JsonPath, AssertJ, and some in-built testing facilities on Spring Framework and Spring Boot for our testing needs. Since the advent of DevOps, there is an increased focus on automation testing and that's why unit testing and integration testing has become important topics on Java Interviews and it's essential for Java developers to have in-depth knowledge about how to test a Spring framework and Spring Boot based Java application.