How to Remove a Key, Value, or Entry from an HashMap in Java 8 - Example Tutorial

In the last article, I have shown how to remove key/value pairs from a map in Java-based upon some conditions like remove all entries where values are greater than some values. I have told you that you must use the Iterator's remove() method for removing mapping while iteration to avoid ConcurrentModificationException, but that's not required anymore in Java 8. From JDK 8 onwards, you can selectively remove mapping without iterating over Map. The JDK 8 API has added several new methods to existing interfaces e.g. java.util.Collection, java.util.Map, Comparator, etc because the interface can now contain concrete methods in the form of static and default methods.

What is happens-before in Java Concurrency? An example

A couple of days ago, one of my readers messaged me on LinkedIn about a Java interview question he has recently faced - what is the happens-before relationship in Java concurrency? What is the benefit of it, and how exactly it works? He kind of has some ideas about that its related to the Java Memory Model and provides some sort of visibility guaranteed but couldn't explain with conviction to his interviewer, particularly with a code example and was a bit disappointed. He then asked me if I can write an article about it. I said you should have read the Java concurrency in Practice book before the interview, that would have helped, but nonetheless, I liked the idea to just provide a quick overview of what is the happens-before relationship between threads in Java.

Top 5 Courses and Books to learn Julia Programming language in 2021 - Best of Lot

Hello guys, if you are looking for a new, modern programming language to learn in 2021, then let me introduce you to the Julia programming language. Julia is a high-level, high-performance dynamic programming language developed specifically for scientific computing, but it has uses in Big Data, Data Science, and other computing-intensive industries. Julia is actually designed to address the requirements of high-performance numerical and scientific computing while also being useful for general-purpose programming. Julia is also one of the most loved programming languages on StackOverFlow's Developer survey and created with the vision to take the best things from other popular mainstream programming languages.

Top 5 courses to learn Pandas and Python Data Analysis in 2021 - Best of Lot

Pandas is one of the most potent and popular Python libraries for Data Analysis. It's also one of the favorite tools for Data Scientist because it helps them in cleaning, transformation, manipulation, and analysis of Data. To be honest, data in the real world is messy, and before you can start with your analysis, you need to clean and transform the data in the format you want. A tool or library like Pandas really helps there. That's why it's essential to learn about Pandas while doing Data Analysis with Python. It's even more critical if you are in the field of Data Science and Data Analysis. If you know Paands, well and good, but if you don't nevermind, as I am going to share some of the best online courses to learn Pandas and Data Analysis with Python in 2021.

Top 5 Data Science and Machine Learning Courses to Learn Online - Best of Lot

Many programmers and Computer Science graduates are moving towards Data Science and Machine learning hoping for better pay and career opportunity and there is a reason for it. Data Scientist and Machine Learning Specialist have been ranked the number one job on Glassdoor for last a couple of years and the average salary of a data scientist is over $120,000 in the United States according to Indeed. Data Science is not only a rewarding career in terms of money but also provides the opportunity to solve some of the world's most interesting problems.  IMHO, that's the main motivation many good programmers are moving towards Data Science, Machine Learning, and Artificial Intelligence.

Top 15 Data Structures and Algorithm Interview Questions Answers for Java Programmer

Data structures and algorithm questions are an important part of any programming job interview, be it a Java interview, a C++ interview, or any other programming language. Since data structures are core programming concepts, it's mandatory for all programmers, to know basic data structures like the stack, linked list, queue, array, tree, and graph. Though trees and graphs are on the tougher side, I still see programmers get familiar will all these. Any list of programming job interview questions is incomplete without questions from data structures and algorithms. Similarly, while going on questions from data structure you may get some programming exercise as well e.g. swapping numbers without temp variable.

Top 5 Best Java 8 Tutorials, Courses, and Books

It's been quite some time since Java 8 was released but the Java community is still buzzing with functional programming and lambda expression. Many developers, programmers, and bloggers have already shared lots of really good tutorials to learn lambda expressions, probably the biggest thing in Java world after Generic was introduced in Java 5. While the term "lambda expression" may sound abstract and academic, Java 8 Lambdas can have a big impact on how you program every day. Java 8 has not only introduced Lambda expressions but also Stream API, Functional interfaces, new Date and Time API, and default methods, which has completely changed the way you write your Java code. As a professional Java developer, you will have to learn Java 8 one day, and it's better to do sooner than later.

How to Find Multiple Missing Integers in Given Array of Numbers with Duplicates in Java?

Hello guys, It's been a long time since I have discussed any coding or algorithm interview questions, so I thought to revisit one of the most popular array-based coding problems of finding missing numbers in a given array of integers. You might have heard or seen this problem before on your programming job interviews and you might already know how to solve this problem. But, there are a lot of different versions of this problem with increasing difficulty levels which interviewers normally use to confuse candidates and further test their ability to adapt to frequent changes, which is key to surviving in the ever-changing software development world.

Top 5 MySQL Courses for Programmers and DBAs to Learn Online - Best Of Lost

Hello guys, if you are interested in learning SQL with MySQL database and looking for some awesome resources e.g. books, tutorials, and online courses then you have come to the right place. In past, I have shared some useful books and tutorials and in this article, I am going to talk about some of the best MySQL online courses from Udemy and Pluralsight which you can join to learn SQL and MySQL from the comfort of your office or home. In the last couple of years, you might have heard the statement that everybody should learn to code, which is great. Coding is now like reading, writing, and speaking skills and in today's Information technology-centric world it is must-have and there is no better way to start coding than learning SQL, the most popular programming language.

Top 5 Courses and Books to learn Rust Programming language in 2021 - Best of Lot

Hello guys, if you are looking to learn a new Programming language that will improve your overall programming skills and practices in 2021, then the Rust programming language can be the right choice. Rust is one of the relatively new (born in 2015) and powerful programming language which combines the power of C++ with the safety of Java and other interpreted languages. When a Programming language is designed, it was either designed for power like C/C++ or for safety like Java, Python, etc. but we didn't have the best of both. There were many attempts to combine the power of C/C++ and safety offered by Java, and it looks like Rust has got that right. Since it was debut in 2015, Rust has gained the attention of the world and the developer community.

Top 5 Books and Courses to Crack Oracle's Java SE 11 Certification | OCAJP 11 1Z0-815 and OCPJP 11 1Z0-816, 1Z0-817

Hello guys, if you are preparing for the OCAJP 11 (1Z0-815)  or OCPJP 11 (1z0-816) exam and looking for some advice on preparation then you have come to the right place. The Java SE 11 Certification is one of the toughest of Java certification at the developer level. It's much harder than OCAJP 8, it's predecessor, and some of the programmers who have attempted it calling it even harder than the professional-level certification like OCPJP 8. In order to crack Java SE 11 certification, you need to prepare hard, but, at the same time, you also need to know which areas you should focus on. What topics should you spend more time on and which books and courses can help you to learn those essential topics?

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 10 Data Science Certification Courses for Python and R Developers - Best of Lot

Hello guys, Data Science, Machine Learning, Deep Learning, and Artificial intelligence are really hot at this moment and offering a lucrative career to programmers with high pay and exciting work. It's an excellent opportunity for programmers who are willing to learn these new skills and upgrade themselves. It's also important from the job perspective because Robots and chatbots are getting smarter day by day, thanks to these technologies, and most likely will take over some of the jobs which many programmers do today. Hence, it's essential for software engineers and developers to upgrade themselves with these skills.

Top 5 Courses to become a Frontend Developer in 2021 - Best of the Lot

Frontend development is one of the critical skills for web developers as there is a lot of demand for programmers with excellent front-end development skills. If you've never experienced client-side web development, learning the plethora of front-end technologies can be difficult, but with proper guidance and choosing the right courses, you can achieve your target. The one thing which I want to tell you that a good knowledge of HTML, CSS, and JavaScript is a must for any front-end developer. Even though we are living in the era of frameworks and libraries, but knowledge of these fundamental technologies cannot be undermined.

5 Spring Framework Books Experienced Java Developers Should Read in 2021

The Spring framework has changed a lot in the last couple of years. We have seen significant releases for Spring, Spring Boot, and Spring Security. These new releases introduced several exciting features to meet the latest software development trends, like Reactive programming, support for Kotlin for developing Spring application, Spring WebFlux - a new framework to build non-blocking and reactive web applications,  and many more. Since the software world is changing and most of the development is happening on Cloud with Microservice architecture leading the way, it's high time that experienced Java developers should upgrade themselves.

Top 5 Java 8 and 9 Courses for Programmers - Best of Lot

Hello guys, if you are looking for some free resources, like books, tutorials, and courses to learn and master new features introduced in Java 8 and Java 9, then you have come to the right place. In the past, I have shared some of the best Java 8 tutorials and books, and in this article, I am going to share some of the best, free Java 8 and Java 9 courses from Udemy and Pluralsight with you. These courses are pretty similar to many paid courses you usually buy, and many of these are made free by just promotional or educational purposes by their instructor. You can join these courses to learn JDK 8 and JDK 9 features in a couple of days.

5 Resources to Create Best Selling Online Courses in 2021

There is something about online training courses that makes learning so easy. They are affordable, convenient, and accessible everywhere. More and more programmers, bloggers, and experts are now teaching online so that now there are so many high-quality courses available on the internet to learn almost anything. It wasn't like that a couple of years ago when books and tutorials were the primary resources for learning new skills, but there is a huge potential still for both learners and creators when it comes to creating and selling online courses. You can easily make 10K USD per month by selling online courses and more importantly can make a difference in people's life.