2023

Spring Boot @Autowired Example - How Autowiring of Beans works in Spring?

Hello guys, if you are wondering how to use @Autowired annotation in Spring Boot and how auto-wiring works in the Spring framework and how the Spring framework magically finds dependency and relevant beans to inject into your program then you have come to the right place. In the past, I have shared how Spring MVC works and in this article, I am going to explain how auto-wiring works in spring and how you can use @Autowired annotation for auto-wiring dependencies in your code. In Spring, you need to know the most important things before starting your coding. From spring 2.5 onwards, the annotations-driven dependency injection was introduced and it is used to inject collaborating beans into the beans. So in this tutorial, we are going to explain how does auto wiring work in spring.

Spring Boot + Angular + Java Project Example and Tutorial

Hello Java programmers, if you are looking for a full-stack Java project with Spring Boot and Angular then you have come to the right place. Earlier, I have shared best Spring Boot courses, books as well as Spring boot + Reactjs project and In this tutorial, we are going to discuss how to create your first application using spring boot and angular. So we are using a simple crud application to build the application here. Here we create a School Classroom Dashboard application that can insert, update, delete and search students. The frontend of the application will be handled by angular and the backend of the system is using the spring boot. This is also a great Spring boot project beginners to do learn Spring boot better. So let's have a look into this.

The 2023 PHP Developer RoadMap

Hello guys, if you want to become a PHP developer in 2023 and looking for guidance like PHP Developer RoadMap, particularly PHP Backend developer roadmap then you have come to the right place. Earlier, I have shared best free PHP courses and MySQL courses for web developers and today, I am going to share how to become a PHP Developer in 2023 and a complete PHP Developer RoadMap which you can follow along. Making web applications can be fun and a promising career since it is insignificant demand and has a respectful salary. Many people are even learning this skill and working as freelancers from home. If you are planning to learn this skill, I will suggest learning the PHP language to make the back-end code of the web apps. This article will help you learn the roadmap to becoming a PHP developer.

Top 5 Common Spring Bean Exception, Error and Solution [BeanDefinitionStoreException, NoSuchBeanDefinitionException, BeanCreationException]

Hello guys, error handling and troubleshooting is an important skill for Java developers. During development you can get variety of exception and sometime they are quite difficult to solve especially if you have no clue what they are and what causing them. Things can be even more difficult if exception is coming from the framework you are using like Spring Framework or Hibernate, that's why its important to know common error and exception for standard framework like Spring. In this article I will explain what BeanDefinitionStoreException, BeanCreationException, NoSuchBeanDefinitionException and BeanDefinitionOverrideException are, what can cause them and how to fix those problems.

How to use Named Query SQL in Spring Framework? Example Tutorial

Hello guys, many Java developers don't know that Spring Framework also provides support for NamedQuery where you can pass parameters in a much readable way by using named placeholders than the default placeholder of ? (question mark) which is used with PreparedStatement in Java. If you want to learn Spring JDBC then you have come to the right place. In the past, I have shared the best Spring Framework courses, books, and tutorials to learn Spring Framework and its different features, and in this example, I will show you how to use NamedQuery in Spring Framework. You can then use this technique to write much more readable queries on the Java layer for your application.

Top 23 Design Patterns Experienced Java Programmers Should Learn

Hello guys, if you want to learn Design Patterns and looking for a comprehensive tutorial which covers all important object oriented design pattern then you have come to the right place. Earlier, I have shared best Design pattern courses and books for experienced developers and in this article, I will introduce you with 23 common object oriented design patterns for writing better code. Design Patterns are tried and tested way of solving a problem within a given context. They are not invented, rather they are discovered, which is also obvious by use of word pattern. By using design pattern, you take knowledge of all wide communities and can safely use it to solve that problem. At times they might not give you perfect solution, require bit of tweaking, but they certainly provides one of the best solution, as long as you use them properly. While doing object oriented development, they are numerous task which appears quite often e.g. creating objects, structuring code, and implementing different behaviors based on different context.

Does Order of Multiple intercept-url's in Spring Security Matters?

Hello guys, one of the frequently asked Spring Security Question is about the order of multiple intercept-urls in Spring security configuration file e.g. applicationContext-security.xml. If you have to define more than one intercept URLS, which order will you define them? Does order even matters? The short answer of this question is, Yes, ordering of intercept URLs in Spring Security configuration file does matter and if you have to define multiple intercept-urls then you define the in a order from most specific to least specific. Why you should that? because Spring security tries to match the URL of every incoming request or outgoing response to the intercept urls in the same order they are declared. So if you declare the least specific URL first then most of the request will match that URL pattern and your more specific pattern will never execute.

How to use State Design Pattern in Java? Vending Machine Example

The State design pattern is a behavioral pattern, first introduced by GOF in their class is book design patterns. State pattern looks similar to Strategy pattern but it helps in managing object state and thus enabling them to behave differently in a different state. In this example, we will take a famous object-oriented design interview question, implementing Vending Machine in Java. In the past, we have solved this problem without using any design pattern, but here we will use state design patterns to create a vending machine with different states. This example will not just help you to understand how to implement State Design Pattern in Java but also gives you experience about when to use State Pattern on your application.

Top 7 Websites to learn HTML and CSS Online for FREE - Best of Lot

Hello guys, if you want to learn HTML, CSS, and Responsive Web Design and looking for best free resources like online courses, books etc then you have come to the right place. Earlier, I have shared best free HTML and CSS Courses, and books and today, I am going to share best places to learn HTML and CSS for FREE. Every web page in this world has at least two programming languages to be designed which are HTML and CSS. These two languages give the design of every page and HTML is responsible for the structure of the web pages such as the buttons the text and so on but CSS is the styling language where you can color the text the buttons the sections adjust the width the height and much more.

How to test a Spring Boot Application using JUnit, Mockito, and @SpringBootTest? Example Tutorial

Hello guys, if you are wondering how to test your Spring Boot application then you are at the right place. In the past, I have shared several Spring and Spring Boot resources like best Spring boot courses, best Spring Boot books, Spring Boot Interview questions and even Spring Boot projects and in this article, I am going to share how to test your Spring Boot application using @SpringBoot annotation. This article will teach you essential concept for testing Spring Boot applications. It's expected that you are know about essentially the fundamentals of Java, Maven and Spring Boot (Controllers, Dependencies, Database Repository, and so on).

10 Reasons to learn JavaScript Programming Language in 2023

Hello guys, if you want to become a web developer or a fullstack web developer who can code frontend, backend, and both web application and mobile apps then you must learn JavaScript. It's one of the most popular programming language with lots of jobs and opportunity and its also very easy to start learning. If you also want to learn JavaScript but not sure whether JavaScript is the right programming language or not, or want to learn JavaScript but not sure whether its worth the effort then you are the right place. Earlier, I have shared best JavaScript courses, books, and best places to learn JavaScript and in this article, I am going to share 10 key reasons to learn JavaScript in 2023.

AES Encryption and Decryption in Java - AES Encoding Decoding Example Tutorial

Hello Java programmers, if you are looking for an example to encrypt and decrypt a test using the AES algorithm in Java then you have come to the right place. Earlier, I have shown you how to Base 64 encode and decode a String in Java, and in this article, I will teach you how to encode and decode a string using AES Algorithm. If you don't know, AES stands for Advanced Encryption Standard algorithm and it is a symmetric block cipher that is used to protect classified information by many Government and Security organizations. You can use AES to encrypt sensitive data in your application config file like database password, user login details and keys etc. In our example we will be using an AES Algorithm with AES - 128, AES has a fixed block size of 128 bits. We will be using a password based secret key.

Difference between Proxy and State design Pattern in Java

Hello guys, if you are preparing for Java interviews and looking for difference between Proxy and State design pattern then you have come at the right place. In the past, I have explained several important object oriented design patterns like State patttern, Strategy, Adapter, Facade, Factory, Observer, Decorator, Command, and Composite Pattern and also shared frequently asked questions on design patterns (See here) and in this article, I am going to share the key difference between Proxy and State Design Pattern in Java and OOP. The difference between Proxy and State pattern comes in both intent and structure, here are the key difference between both Proxy and State Design Pattern in Object oriented programming.

How to use props in React.js? Functional and Class Component + Properties Example Tutorial

Hello guys, If you have ever worked with React.js, one of the popular JavaScript library for building UI components then you definitely know what components are. A React application is made of several components and that is why components in React are defined as the building blocks of the application. In simple terms, a component is a class or function that can accept input and return a piece of code that defines a UI. Every React component can have input. These inputs are known as props. Props stand for properties and they are optional. A component works fine without props but they are one of the most useful parts of React.

3 Best ways to learn Angular Framework in 2023

Hello guys, if you want to learn Angular in 2023 but not sure how and where to start then you have come to the right place. Earlier, I have shared best Angular courses, books, tutorials, and interview questions and in this article, I will share how to learn Angular from scratch in 2023. Angular is Type-Script based frontend framework that is used to create single-page web applications. Angular has been active in the web development community for a long time. It is one of the first frontend JavaScript frameworks.

[Solved] How to Implement Binary Search in Java without Recursion? Iterative Algorithm Example Tutorial

Hey Java programmers, if you want to implement a binary search in Java, and looking for both iterative and recursive binary search algorithms then you have come to the right place. Earlier, I have shared the free courses to learn Data Structure and algorithms in Java, and today, I am going to teach you an important algorithm. In computer science, a binary search or half-interval search is a divide and conquer algorithm which locates the position of an item in a sorted array. Binary search works by comparing an input value to the middle element of the array. The comparison determines whether the element equals the input, less than the input or greater.

Top 20 Amazon and Google Programming Interview Questions for Software Developers

Hello, In this article I am going to sharing some frequently asked programming job interviews from technical giants and startups. If you are going for a programming job interview with Microsoft, Google, or Amazon, you better be prepared for all kinds of questions. These companies are known to ask tough questions, tricky puzzles, and lots of data structure and algorithm questions. Since it's hard to prepare all these in a short time, it makes sense to at least have a good idea of frequently asked programming questions in Microsoft, Google, or Amazon.

Difference between Statement vs PreparedStatement vs CallableStatement in Java JDBC

Hello Java programmers, if you are looking to find out the difference between Statement, PreparedStatement, and CallableStatement in Java then you have come to the right place. Earlier, I have shared common JDBC Interview Questions and in this article, I am going to explain what is the real difference between these Statement types in Java and when to use Statement, PreparedStatement, and CallableStatement in Java programs. JDBC API provides several classes and interfaces for various things, but three of the most important types of Statement classes are Statement, PreparedStatment, and CallableStatement. They are designed to execute different types of SQL queries.

How to Create Auto Incremented Identity Column in SQL Server, MySQL, and Oracle? Example

Automatic incremented ID, Sequence, or Identity columns are those columns in any table whose value is automatically incremented by database based upon predefined rule. Almost all databases e.g. Microsoft SQL Server, MySQL, Oracle or Sybase supports auto-incremented identity columns but in different ways like Oracle provides a SEQUENCE object which can be used to generate automatic numbers, Microsoft SQL Server up to 2008 version provides IDENTITY() functions for a similar purpose. Sybase also has IDENTITY function but little different than SQL Server and MySQL uses auto_incremented keyword to make any numeric column auto-incremented.

Difference between close and deallocate cursor in SQL

Cursor in a database is used to retrieve data from the result set, mostly one row at a time. You can use Cursor to update records and perform an operation a row by row. Given its importance on SQL and Stored procedures, Cursor is also very popular in SQL interviews. One of the popular SQL questions on Cursor is close vs deallocate. Since both of them sounds to close the cursor, once the job is done, What is the real difference between close and deallocate of Cursor in SQL? Well, there is some subtle difference e.g. closing a cursor doesn't change its definition. In Sybase particular, you can reopen a closed cursor and when you reopen it, it creates a new cursor based upon the same SELECT query.

10 Examples of Stream Class in Java 8 [ map + filter+ flatmap + collect + findFirst ]

There is no doubt that Stream class is one of the most important class of Java SE 8 API and a solid knowledge of this class is needed to write modern day Java code. There is no excuse to write the Java code we used to write in imperative style like using loops and not using functional programming idioms. In fact, now it's one of the best practice in Java to favor functional programming and immutable data structure over imperative programming. More and more Technical Leads are enforcing developers to learn Java 8 and write better code leveraging improved API. The Java designers has done a fantastic job to convert any collection to Stream by adding stream() method into Collection interface.

Difference between ByteBuffer vs byte array in Java

There are several differences between a byte array and ByteBuffer class in Java, but the most important of them is that bytes from byte array always reside in Java heap space, but bytes in a ByteBuffer may potentially reside outside of the Java heap in case of direct byte buffer and memory mapped files. Buffer is a byte array like abstraction which was introduced in Java NIO release to read and write data from FileChannel. It is extensively used in Java NIO for transferring data from one place to another and its also an essential Java concepts to know for any backend developer, particularly those who wants to create non-blocking server application using NIO in Java.

Can you declare Abstract Class or Method Final in Java? If not, why?

If you are wondering whether you can use both abstract and final modifier together with a class or method in Java then you are not alone. This is one of the frequently asked, theory based Java questions which is sometime tricky to answer, particularly if you don't have complete knowledge of Java fundamentals. The answer of this question is No, you can not declare abstract class or method final in Java because both abstract and final keywords are mutual exclusive. Anything which is abstract cannot be final and vice-versa. It's like a person cannot be living and dead at the same time.

Difference between var, let, and const in JavaScript? Example Tutorial

Hello guys, there are many ways to declare variables in JavaScript like var, let, and const and many JavaScript developer get confused when to use which keyword for declaring a variable in JavaScript. If you also have same doubt and want to understand the difference between var, let, and const in JavaScript then you have come to the right place. This is one of the popular JavaScript interview questions and frequently asked during telephonic and face-to-face round of web developer interview. Knowing the difference will not only make you answer this question better during interview but also to write better JavaScript code in your day-to-day work. Earlier, I have shared the best books and JavaScript courses for beginners and in this article, I will tell you the difference between var, let, and const and when to use them. They are three different ways to declare variables in JavaScript.

The 2023 Android Developer RoadMap

Hello guys, if you want to learn Android in 2023 or want to become an Android developer and looking for an Android Developer RoadMap then you have come to the right place. Earlier, I have shared best Android Courses and Books and in this article, I am going to share with you one of the most comprehensive Android Developer RoadMap you can find online. I love these Roadmap as they provide a comprehensive picture of what exactly you need to learn to become a professional Android developer and while they give more than what you need, its still better to have more than less as you can always learn remaining skills to become a better Android developer.

Top 15 Java NIO, Socket, and Networking Interview Questions Answers for Experienced Developers

Hello guys, if you are preparing for Java developer interview then you may know that Networking and Socket Programming is one of the important areas of Java programming language, especially for those programmers, who are working in client server-based applications. Knowledge of important protocols like TCP and UDP in detail is very important, especially if you are in the business of writing high-frequency trading applications, which communicate via FIX Protocol or native exchange protocol. In this article, we will some of the frequently asked questions on networking and socket programming, mostly based around TCP IP protocol.

The 2023 Data Scientist and Data Engineering RoadMap

Hello guys, if you want to become a Data Scientist or Data Engineer in 2023 and looking for guidance like how to become a Data Scientist and Data Engineer in 2023 then you have come to the right place. In the past, I have shared best Data Science courses, tools, and best websites to learn Data Science and in this article, I am going to share the complete Data Scientist and Data Engineering RoadMap. This roadmap include all the skills, tools, and technologies you need to become a professional Data Scientist in 2023. While this roadmap is very comprehensive and contains tens of skills, tools, libraries, framework and programming language, they are divided into different categories like mandatory, good to know and other choices.

Difference between IsNull and Coalesce in Microsoft SQL Server (with Examples)

Even though both ISNULL and COALESCE is used to provide default values for NULLs there are some key differences between them like ISNULL() is a T-SQL or Microsoft SQL Server-specific function or operator, and datatype and length of the result depends upon a parameter, but COALESCE is a SQL ANSI standard, it can accept more than one parameter and unlike ISNULL, the result doesn't directly depend upon a parameter, it is always the type and length of the value returned. Also, what is the difference between COALESCE and ISNULL is one of the frequently asked Microsoft SQL Server interview questions, and knowing these differences can help in both your day-to-day SQL development works and during job interviews.

The 2023 Golang Developer RoadMap

Hello guys, if you want to become a Golang Developer in 2023 or want to learn Golang in depth then you have come to the right place. Earlier, I have shared best online courses to learn Golang and Golang projects for beginners and in this article, I am going to share the complete Golang Developer RoadMap which you can follow to become a Golang Developer you always wanted to be. This is one of the most comprehensive Golang Developer RoadMap you can find on internet. It not only list all the mandatory tech skills you need to learn for Golang Backend development but also all the options and extra skills which can truly make you a competent Golang Developer in 2023. If you are wondering where to learn those skills then don't worry, I have also shared both free and best online resources to learn those skill in 2023.

What is Generator Function in JavaScript? Example Tutorial

Hello guys, Functions are an essential part of JavaScript programming. Basically, a function is a piece of code that can take inputs and return outputs. Moreover, a function can be executed at any time and any number of times. When a regular function is called, it executes from top to bottom. Its execution ends when the function body ends or a return statement is encountered. But JavaScript provides a special kind of function that works in a different. These functions are called generator functions and they were introduced in ES6. In this article, we will discuss what are generator functions and how to use them with the help of an example. It's also a popular JavaScript interview questions, commonly asked to experienced developers.

What is state in React.js? useState Hook Example Tutorial

Hello guys, I have just started a new series, React for Java developers and I am going to publish React tutorials and examples to teach React.js, one of the most popular frontend libraries to Java developers. Since most full-stack Java development is happening on React and Spring Boot, it makes sense for Java developers to learn React.js. In the past, I have also shared both best React courses and books, as well as The React Developer RoadMap, which provides all the tools, libraries, and resources you need to become a proficient React Developer.

React Project Example - How to create a React application using Redux hooks?

Redux is the most popular state management library. It is often used with React apps that are huge in size and state are shared among multiple components. Redux is a complex library to understand and even more complex to implement. It was even more complex and complicated before the introduction of react-redux hooks. Earlier, the connect method provided by Redux was used to connect React with the Redux store. Using connect method with other methods such as mapstatetoprops was complicated. But with the introduction of react-redux hooks, it is easy to use redux with redux. In this article, we will discuss what are react-redux hooks and how to use them with React.

The 2023 Blockchain Developer RoadMap

Hello guys, if you want to become a Blockchain Developer in 2023 and looking for guidance then you have come to the right place. Earlier, I have shared best Blockchain courses, books, and best websites to learn Blockchain technology and today, I am going to share how you can become a Blockchain Developer in 2023. Blockchain solutions are one of the most talked-about examples of technological innovation in recent times. Decentralization, transparency, and security in blockchain-based systems and applications can offer new routes for digital transformation. Amidst the growing hype around blockchain technologies, the role of a blockchain developer has become crucial for the emerging ecosystem.

Difference between SubStr vs SubString function in JavaScript - Tutorial Example

Hello guys, if you are wondering what is difference between SubStr() and SubString() function in JavaScript then you have come to the right place. JavaScript provides two similar-looking String manipulation functions, substr and substring, though both are used to get a substring from a String, there is a subtle difference between substring and substr method in JavaScript. If you look at their signature, both substr(to, length) and substring(to, from) both take two parameters, but substr takes the length of the substring to be returned, while substring takes end index (excluding) for substring. This main difference will be more clear when we will see a couple of examples of using substr and substring in JavaScript code.

Top 25 Vue.js Interview Questions and Answers for Web Developers

Hello guys, if you are preparing for Vue.js interviews and looking for some frequently asked Vue.js questions from interviews then you have come to the correct place. Earlier, I have shared React.js Interview questions and JavaScript questions and in this article, I am going to share common Vue.js Interview questions for 1 to 2 years experienced web developers. With the success of libraries like React.js, developers around the globe are leaning more towards such flexible technologies. Though full-fledged frameworks like Angular are also popular and widely used, developers want flexibility.

Top 16 Lambda Expressions and Stream API Interview Questions Answers for Experienced Java Programmers

For a long time my readers were asking about some Java 8 interview questions, particularly on lambda expression, streams and around language changes e.g. default methods, method reference and functional interface. Finally, I am able to put some common Java 8 interview questions on lambda expression and Stream API and essential functional programming concepts like map, flatmap, and reduce together, which I going to share with you in this article, but before that, let's talk a little bit about impact of Java 8 in Java Developers interviews and why it's imperative for Java programmers to learn Java 8, particularly Lambda and Stream API.

How to use hooks like useState, useEffect and useDispatch in React.js? Example Tutorial

Hello guys, if you want to learn about Hooks in React.js like useState, useSelector, useEffect, and useDispatch then you have come to the right place. In the past, I have shared the best React courses, websites, and books and in this article, I am going to show you what is React hooks and how they make coding and statement management easier in React.js. If you remember, React.js is created by Facebook and ever since it came out in 2013 and since then, it has become one of the biggest players in the front-end development community. Today, React.js demand for frontend development is more than any other framework or library. There are several reasons for its popularity. React is flexible, easy to learn, programmer-friendly, and most importantly, it's high performing.

10 Tools Cyber Security Professional and Pen Tester Should Learn in 2023

Hello guys, if you want to become a Pen Tester, Cyber Security Engineer or Ethical Hacker in 2023 and looking for the best tools then you have come to the right place. Earlier, I have shared best Cyber Security courses, free Pen Testing Courses, and Ethical Hacking courses and in this article, I am going to share best tools every Cyber Security Engineer and Pen Tester should learn in 2023 to do their job effectively. Suppose you become a penetration tester and learn the cyber security field. In that case, you need to know many tools that will help you scan the networks and system for vulnerabilities and other tools for exploring them. This article will provide you with the most used tools for finding these vulnerabilities and how to exploit them.

How to use useDispatch and useSelector? React Hooks Example Tutorial

Hello guys, if you are learning about React hooks and wondering how to use useDispatch and useSelector hooks in React application then you have come to the right place. Earlier,, I have shared the best React courses, websites, and books and in this article, I am going to show you how React hooks make coding and statement management easier than it was before. The introduction of React hooks changed a lot in the react application development. Developers moved from complicated and length class-based components to simpler functional components that can do the same work in fewer lines of code.

Top 35 React.js Interview Questions Answers for Fullstack Java Developers

Hello guys, if you are preparing for React developer interviews and looking for frequently asked React.js interview questions then you have come to the right place. Earlier, I have shared the best courses, books, and websites to learn React.js and in this article, I am going to share 35 frequently asked React.js interview questions, suitable for 1 to 2 years experience developers. ReactJS is one of the most recently built open-source front-end programming languages. It came directly from Facebook's headquarter back in 2011. Earlier Recat.js was only limited to Facebook but now, it is one of the most extensively used programming languages all across the world.

The 2023 Machine Learning Engineer RoadMap

Hello guys, if you want to become a Machine Learning Engineer in 2023 and looking for Machine Learning RoadMap then you have come to the right place. I love roadmaps and in the past, I have shared Java Developer RoadMap, Python Developer RoadMap, and Machine Learning courses and today, I am going to share with you The 2023 Machine Learning Engineer RoadMap. Machine learning is a good career nowadays since most companies implement them into their services to deliver a better user experience. Data scientists also use them to make predictions for better decision-making and other things. If you want to become a machine learning engineer and feel confused about starting, complete reading this article.

Top 15 Node.js Interview Questions Answers for Fullstack Developers

Hello guys, if you are preparing for full stack web developer interviews then you should prepare for Node.js as well, particularly if you are a JavaScript developer. Node.js is one of the most popular terms in the web development community. It is heavily used in server-side development. It can be used with different databases such as MongoDB and SQL. There is a huge demand for Node.js developers in the job market. The interview can be tough because Node.js is wide and a person needs a considerable amount of practical experience to crack it. In the past, I have shared JavaScript interview questions, Angular interview questions as well as React Questions, and in this article, we will discuss the top 15 important and commonly asked Node.js questions with answers.

10 Reasons to Learn React Native for App Development in 2023

Hello guys, if you want to get into App development in 2023 then you have a couple of choices. For example, you can learn Flutter and React Native to develop cross platform apps, or you can learn Android or iOS to develop native apps. Android has been my favorite because you can use Java programming language to code Android application and being a Java developer, that was the easiest way to get into App development but if you are coming form JavaScript background then learning Java or Swift (which is required for iOS app development) could be difficult. You can either learn Dart to use Flutter or you can stick with JavaScript and learn React Native, which I think the best way for a JavaScript developer to get into App development in 2023 but if you are still not convinced, In this article, I am going to share 10 reasons to learn React Native, which can help you make a decision on which technology you should learn for app development in 2023.

What is a Functional interface in Java 8? @FunctionalInterface Annotation Examples Tutorial

Hello Java programmers, if you are wondering what is a functional interface and what is the role of @Functional annotation in Java then you have come to the right place. Earlier, I have shared the best Lambda and Stream courses and books, and in this article, I will explain and teach you how to create a functional interface in Java. A functional interface is nothing but an interface with just one abstract method like Runnable, Callable, Supplier, Predicate, etc. You can use @Functional annotation to mark that this is a functional interface. If a function expects a functional interface then you can also pass a lambda expression to it and that's the main benefit of a Functional interface in Java. This is also a popular Lambda Expression Interview question so, knowing this topic in depth is also better for interviews.

Difference between char, varchar, nchar and nvarchar data types in SQL Server? Example

What is the difference between char and varchar in SQL, followed by nchar and nvarchar, is one of the popular SQL interview questions, and surprisingly not every programmer knows this basic difference. If you go with the name, which you should, then you can figure out that char is a fixed-length data type while varchar should be a variable-length data type. Though all char, varchar, nchar, and nvarchar are used to store text or String data there are subtle differences between them. As I said char is fixed length, which means a variable or a column like Zipcode char(10) will take only 10 bytes to store data, including space.

3 Best Spring Security Online Training Courses for Java Developers in 2023 [UPDATED]

Spring Security is one of the leading open-source, security frameworks that allow you to implement security in Java-based web applications. It provides several security features like authentication, authorization, the remember me functionality out-of-the-box, which means you can directly use them without adding code or changing your class. Yes, Spring Security implements security at the application level i.e. you can even secure your non-secure resource without modifying them. It is also the leading framework to secure RESTful Web Services. Because of all these, the demand for Java developers with good knowledge of Spring Security is very high.

Top 5 Online Courses to Learn C Programming in 2023 - Best of Lot

Hello guys, today, I will talk about one of the oldest, reliable, powerful programming languages that have survived for 50 years. Yes, that's right, 50 years. It's a great achievement for any technology to remain relevant for such a long period. If you don't know, the C Programming language is one of the first general-purpose programming languages, invented by Dennis Ritchie and Ken Thomson around 1969. Ken was writing UNIX, another accessible technology that has survived for 50 years around the same time and needed a programming language that can do all kinds of tasks; the result was a C programming language.

3 Ways to Learn React.js for web development in 2023 - Best of Lot

Hello guys, if you want to learn React.js in 2023 and looking for best way to learn React.js in quick time then you have come to the right place. Earlier, I have shared React.js Developer RoadMap as well best React courses, books, websites, and React projects for you and in this article, I am going to share what is the best way to learn React.js in quick time and also in depth. But, before that, let's find out what is React.js and why every web developer should learn React.js in 2023. According to the Stack Overflow developer’s survey, React.js surpassed jQuery to become the most popular web framework in the world. Today, React is the most widely used technology for frontend development. Basically, React is a JavaScript library created and maintained by Facebook. It is used to create interactive and dynamic web components.

10 Reasons to Learn SQL for Programmers and Software Developers in 2023

Hello guys, if you are on the fence whether to learn SQL or not, or want to learn SQL but not sure whether learning SQL is worth your time and effort then you have come to the right place. Earlier, I have shared best SQL books and courses to learn SQL for Beginners and in this article, I am going to share 10 Reasons to learn SQL. From my 18 years of experience as Software developer and 12 years as a blogger I can safely say that you should learn SQL. In all of these times, I have constantly worked with SQL in my projects and job. While database changes form Oracle to MySQL, to SQL Server, and now PostgreSQL but the knowledge of SQL still pays off.

5 Examples of GROUP BY Clause in SQL with Aggregate Functions

There is no doubt that SQL is an essential skill and every programmer, developer, DevOps, and Business analyst should know SQL. If you want to learn SQL from scratch then you have come to the right place. Earlier, I have shared many SQL interview questions and the best SQL courses for beginners, and today, I am going to share some GROPU By examples in SQL to write aggregation queries. THE GROUP BY clause in SQL is another important command to master for any programmer. We often use the GROUP BY command along with a select clause for reporting purposes, since the GROUP BY clause is mainly used to group related data together it's one of the most important SQL commands for reporting purposes.

Strategy Design Pattern in Java using Enum - Tutorial Example

Hello guys, how are you doing? I hope you all are fine and doing good in your life and career. Today, I am going to talk about the Strategy pattern, one of the useful design and coding pattern which will help you to write flexible code. The code which can withstand the test of time in Production. I'll also teach you how you can use Enum to implement the Strategy design pattern and Open Closed design principle better in Java. I have said this before that Java Enum is very versatile and can do a lot more than you normally expect from it. We have seen a lot of examples of Enum in my earlier posts like writing thread-safe Singleton using Enum and 10 ways to use Enum in Java.

Top 30 Scala and Functional Programming Interview Questions and Answers

Hello guys, if you are preparing for Scala Developer interview and looking for frequently asked Scala questions for practice then you have come to the right place. Earlier, I have shared best Scala courses, Scala books, and best Scala Frameworks and in this article, I am going to share 30 Scala Questions from past interviews. Scala is a programming language which aims to provide best of both object-oriented programming and functional programming world. It not only allows you to construct elegant class hierarchies for maximum code reuse and extensibility but also allows you to implement their behavior using higher-order functions and other functional programming technique. It is touted as one of the languages which can probably take over Java, though it didn't happen especially after Java 8 release which also provides some functional programming tools to Java e.g. lambda expression and stream.

Top 10 Free Courses to Learn Docker in 2023 - Best of Lot [UPDATED]

I have been answering a lot of questions about what programmers should learn in 2023, and Docker Container is one such skill. Docker and containers are a whole new way of developing and delivering applications and IT infrastructure. In this post, I'll talk about what Docker is and why a programmer should learn Docker. In today's world of massive scalability, where every single mobile app and web application needs to support billions of users (think of YouTube, WhatsApp, Uber), software application development and deployment have become increasingly complex. Gone are the days when the software is developed by a small team of onshore people.

Top 10 Data Science Certification Courses for Python and R Developers in 2023 - 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 35 T-SQL and Microsoft SQL Server Interview Questions and Answers for 2 to 5 Years Experienced

Hello guys, if you are preparing for Java developer interview where Microsoft SQL Server is listed as mandatory and required skill or you preparing for a junior DBA role for Microsoft SQL Server and looking for common SQL Server interview questions for practice then you have come to the right place. Earlier, I have not only shared SQL Server courses for beginners but also 50+ SQL and Database Questions for programmers and DBA. You an also check them to get yourself familiar with generic SQL concepts like normalization, joins, aggregation, partitioning, indexing, and transaction along with these SQL Server specific questions which focuses mainly on T-SQL and SQL Server functionalities and how general SQL commands behave in Microsoft SQL Server.

12 Examples of Kubectl command in Kubernetes in Windows and Linux

Hello guys, if you are working with Kubernetes pods like deploying your application, starting and stopping them by scaling to zero instances, while you just want to see logs or want to login into the Kubernetes pods itself, you must know how to use kubectl commands to do all these task. Since most of the companies, both big and small are using Kubernetes to deploy services on cloud, its imperative for Java developers and other Software developers to get familiar with the kubectl command. We deploy our Java Microservices on Kubernetes mainly because Kubernetes can start the services automatically when it goes down. We have different Kubernetes clusters for different environments like DEV, UAT, and PRODUCTION and I often switch between those cluster using kubectl commands to check the status of our Java services or interact with them.

Template Method Design Pattern in Java? Example Tutorial

Template Method Pattern defines a sequence of steps of an algorithm but let you free to implement those steps on your way. You cannot change the algorithm but you can define how those steps should behave. To make sure that you cannot change the algorithm, template methods are usually made final in Java, which is also a good use case of when to make a method final in Java. The subclasses are still allowed to override the steps but as I said, they are not allowed to change the sequence. It can also be provided a default implementation for one or more steps. Let us look at the following example to understand Template Method Pattern. A Template method pattern provides a skeleton for performing any sort of algorithm or an operation, and it allows the sub-classes to re-define part of the logic.

How to check if a String has all unique characters in Java? [Solved]

Hello guys, its been long time since I shared any interesting coding problem but the wait is over. Today, I am going to share one interesting and popular String based coding problem which you would love to solve. Today's coding challenge is to find out if a given string has all unique characters or not, for example, if given String is "Java" then your function should return false because all styles from this String are not unique. On the other hand, if the given String is "Python," then your function should return true because all characters are unique in this String. Btw, don't just jump on the solution if this is ever asked to you on Interview; instead, you should ask a couple of good questions to demonstrate your requirement gathering skill and attention for details.

How to enable disable Form elements using jQuery? Example Tutorial

In last couple of tutorials you have learned how to get all selected checkbox and radio buttons, and in this tutorial, you will learn how to enable/disable form elements using jQuery. A form element e.g. a text field, radio buttons and checkbox, all represented using input tag can be enabled or disabled by adding an attribute called "disabled". It's similar to "checked" attribute we have seen for checkbox and radio buttons. If this attribute is not present then element is enable, but if this attribute is present then you can use disabled=true to disable the form element and disabled=false to enable the form elements as shown in our example. Like previous example of checking/unchecking checkbox, you can use prop() jQuery function to enable/disable form element if you are running on jQuery 1.6 or higher version and attr() function if you are running on jQuery 1.5 or lower version.

Top 10 Free Courses to Learn Python in 2023 - Best of Lot

There is no doubt that Python is currently the world's #1 programming language and the biggest advantage of that is it's bringing more and more people into the programming world. In recent years, I have seen more people learning Python than any other language, yes, not even JavaScript. Many of them learning Python to explore some awesome Data Science and Machine learning libraries provided by Python. Some people are also learning Python for web development and there are still many developers who are learning Python for scripting and automating trivial tasks. It doesn't matter why you are learning Python at this moment, it's a great thing in itself that you have decided to learn Python.

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