Is Java Pass by Value or Pass by Reference? Example

Hello guys, Does Java is pass by value or pass by reference is one of the tricky Java questions mostly asked on both beginner and experienced level Java developer interviews. Before debating whether Java is pass by value or pass by reference lets first clear what is pass by value and what is pass by reference actually means?. This question has its origin in C and C++ where you can pass function parameter either value or memory address, where value is stored (pointer). As per Java specification everything in Java is pass by value whether its primitive value or objects and it does make sense because Java doesn't support pointers or pointer arithmetic, Similarly multiple inheritance and operator overloading is also not supported in Java.

Difference between CAST, CONVERT, and PARSE SQL Server? Example Tutorial

Though all three, CAST, CONVERT, and PARSE are used to convert one data type into another in SQL Server, there are some subtle differences between them. The  CAST method accepts just two parameters, expression, and target type, but CONVERT() also takes a third parameter representing the format of conversion, which is supported for some conversions, like between character strings and date-time values. For example, CONVERT(DATE, '2/7/2015', 101) converts the character string '2/7/2015' to DATE using DATE format 101, representing United States standard.

Difference between @Mock and @MockBean in Spring Boot? Example Tutorial

Hello guys, if you are writing test for your your Spring Boot application then Sooner or later, you'll come across @Mock and @MockBean annotations while testing your Spring Boot application. Both annotations generate fake or Mock  objects, but for different reasons and its important for Java and Spring Boot developer to know the correct difference and when to use @Mock and @MockBean while writing tests. It's possible that this will seem perplexing at first, in face I was confused for a long time until I did my research and cleared it up. But, you don't need to scan through internet, In this blog article, I'll clear up any misunderstandings and clarify the difference between @Mock and @MockBean when testing Spring Boot apps.

Difference between State and Strategy Design Pattern in Java

Hello guys, if you are wondering what is difference between State and Strategy pattern in Java then you are at the right place. In order to make proper use of State and Strategy design Patterns in any Java application, it's important for a Java developer to clearly understand the difference between them. Though both State and Strategy design patterns have a similar structure, and both of them are based upon the Open closed design principle, which represents 'O' from SOLID design principles, they are totally different on their intent. The strategy design pattern in Java is used to encapsulate a related set of algorithms to provide runtime flexibility to the client. 

Decorator Design Pattern in Java with Example Java Tutorial

Hello guys, if you want to learn about Decorator design pattern in Java then you are at the right place. I was thinking to write on decorator design pattern in Java when I first wrote 10 interview questions on Singleton Pattern in Java. Since design patterns are quite important while building software and it’s equally important on any Core Java Interview, It’s always good to have a clear understanding of various design patterns in Java. In this article, we will explore and learn the Decorator Design pattern in Java which is a prominent core Java design pattern and you can see a lot of its examples in JDK itself. 

Data Access Object (DAO) design pattern in Java - Tutorial Example

Data Access Object or DAO design pattern is a popular design pattern to implement the persistence layer of Java application. DAO pattern is based on abstraction and encapsulation design principles and shields the rest of the application from any change in the persistence layer e.g. change of database from Oracle to MySQL, change of persistence technology e.g. from File System to Database. For example, if you are authenticating the user using a relational database and later your company wants to use LDAP to perform authentication. If you are using the DAO design pattern to access the database, it would be relatively safe as you only need to make a change on Data Access Layer. DAO design pattern also keeps the coupling low between different parts of an application.

How to Convert a Map to a List in Java - Example Tutorial

Hello guys, if you are wondering how to convert a Map like HashMap or TreeMap to a List like ArrayList or LinkedList in Java then you are at the right place. Earlier, I have shared 10 examples of converting a List to Map in Java and this article, I am going to share my tip to convert a given Map to a List in Java. Map and List are two common data structures available in Java and in this article, we will see how can we convert Map values or Map keys into List in Java. The primary difference between Map (HashMap, ConcurrentHashMap, or TreeMap) and List is that Map holds two objects key and value while List just holds one object which itself is a value. 

How to use mkdir command to make directories in Linux and UNIX? mkdir -p Example

One of the most common tasks in any Linux is creating directories, and most of us spend a lot of time creating complex directory structures in UNIX and Linux.  I am sure you know about the mkdir command, we have been using this command in almost every operating system like DOS, Windows, Linux, OS/2, Solaris, or any other *NIX operating system. It is one of the basic commands but as important as find, grep or chmod.  mkdir stands for "make directory" and this command is literally used to create directories. Suppose, you need to create a directory tree-like /opt/software/java/app/config, how are you going to create these directories? One by one right? Well, yes you can use mkdir and command to create these directories one by one as shown in below example :

How hostname to IP address Conversion works in Linux? nslookup Example

One of my favorite Linux Interview questions is about how to convert hostname to IP address in Linux? These questions not just test the candidate's basic Linux command skills but also shows his understanding of how name resolution works in UNIX or Linux? Many developers, software engineers, and support professionals don't really know how Linux converts a hostname into IP address or what happens when they type http://www.amazon.com in their browser in UNIX? They are not really familiar with how the name amazon.com is resolved to an IP address.

How to Delete Empty Files and Directories in UNIX or Linux Host? find Command Example

Deleting empty file and directory in Unix

Hello guys, if you are wondering how to find and remove all empty files and directories from a Linux host then you are at the right place. Earlier, I have shared Linux command to free disk space by removing big files and directories and in this article, I will share find command you can use to remove empty files and directories. Many times we need to find and delete empty files or directories in UNIX/Linux. Since there is no single command in Unix/Linux which allows you to remove empty files or empty directories rather we need to rely on find command and xargs command. 

4 Example to Iterate over Map, HashMap, Hashtable or TreeMap in Java

There are multiple ways to iterate, traverse or loop through Map, HashMap, or TreeMap in Java and we are all familiar with either all of those or some of those. But to my surprise, one of my friends was asked in his interview (he has more than 6 years of experience in Java programming) to write code for getting values from HashMap, Hashtable, ConcurrentHashMap, or TreeMap in Java in at least 4 ways. Just like me he was also surprised by this question but written it. I don't know why exactly someone asks this kind of java interview question to a relatively senior java programmer. Though my closest guess is to verify that whether he is still hands-on with coding in java. 

10 Examples of HashSet in Java - Tutorial

HashSet in Java is a collection that implements the Set interface and is backed by a HashMap. Since HashSet uses HashMap internally it provides constant-time performance for operations like add, remove, contains and size give HashMap has distributed elements properly among the buckets. Java HashSet does not guarantee any insertion orders of the set but it allows null elements. HashSet can be used in place of ArrayList to store the object if you require no duplicate and don't care about insertion order.

Difference between bitwise and logical AND, OR Operators in Java? Examples

Java beginners often ask the same type of questions, and of them is what is the difference between & and && operator in Java or the difference between | and || operators? The standard answer to this question is well, the main difference between & and && is that the former is a bitwise operator, and && is a logical operator in Java. That's academic until you clearly explain the difference in working of & and && or | and ||. For absolute beginners, & is used to represent AND logic operation in Java and | is used to represent OR logic operation.

What is NavigableMap in Java ? TreeMap, headMap, tailMap, and subMap Examples

Hello guys, if you are wondering what is NavigableMap and why should Java developer know about it you are at right place. NavigableMap in Java is an extension of SortedMap  like TreeMap which provides convenient navigation methods like lowerKey, floorKey, ceilingKey, and higherKey. NavigableMap is added on Java 1.6 and along with these popular navigation methods it also provides ways to create a Sub Map from existing Map in Java, like headMap whose keys are less than the specified key, tailMap whose keys are greater than specified key and a subMap which strictly contains keys that falls between toKey and fromKey. 

Why use SerialVersionUID inside Serializable class in Java? Example

Serialization and SerialVersionUID always remain a puzzle for many Java developers. I often see questions like what is this SerialVersionUID, or what will happen if I don't declare SerialVersionUID in my Serializable class? Apart from the complexity involved and rare use, one more reason for these questions is Eclipse IDE's warning against the absence of SerialVersionUID e.g. "The Serializable class Customer does not declare a static final SerialVersionUID field of type long". In this article, you will not only learn the basics of Java SerialVersionUID but also its effect during the serialization and de-serialization process. 

Object Oriented Programming Example in Java? Tutorial

I remember when I was doing my engineering, the OOPS concept was in the first semester. Back then it looks like some alien things to me, because I have never done programming and even the smallest program we get to write like checking whether the number is palindrome or not, or printing the Fibonacci series, we never really needed to use OOPS. When needed, I just memorize things and write them down in exams :). That worked, I passed the exam but effectively I didn't learn OOP or Object Oriented Programming on those days.

Difference between Checked vs Unchecked Exception in Java? Example

Checked and Unchecked Exception is two types of Exception exist in Java. Though there is no difference in functionality and you can very achieve the same thing with either checked Exception or Unchecked Exception, there is some difference on exception handling part. In this Java tutorial we will see what is checked and Unchecked Exception in Java, Examples of Checked and Unchecked Exception and most importantly we will learn when to use Checked Exception and when to use Unchecked Exception in Java and lastly we will see the difference between checked and unchecked exception to understand things better. 

[Solved] How to solve java.lang.UnsatisfiedLinkError: no ocijdbc11 in Java with Oracle 11g, 12c, 19c and 21c

"java.lang.unsatisfiedlinkerror no ocijdbc11 in java.library.path" error comes when you try to connect to Oracle 11g database using OCI (thick) driver by using tns name, but the ocijdbc11.dll file is not available in PATH or java.library.path environment variable. ocijdbc11.dll is a native library and if you know Java searches native library in PATH or a location specified by java.library.path system property, if it doesn't find the dll, then it throws java.lang.unsatisfiedlinkerror no ocijdbc11 in java.library.path error. This dll is usually found in C:\Programs\Oracle\ora11g\bin\ocijdbc11.dll, but it could vary depending upon your Oracle installation.

How to fix java.lang.UnsupportedClassVersionError: Bad version number in .class files? Example

How to fix Bad version number in the .class file

"java.lang.UnsupportedClassVersionError: Bad version number in .class file" is a common error in Java programming language which comes when you try to run a Java class file which was compiled by different version of Java compiler than then JRE version you are using to run it. In our last article, we discussed that how to resolve Java.lang.UnSupportedClassVersionError and found that it comes when a major and minor version of the class is not supported by Java virtual machine or JRE running the program. Though "java.lang.UnsupportedClassVersionError: Bad version number in .class file" is a little different than that of its manifestation and Cause, both are related to the mismatch in compiler javac and runtime java version. 

How to Fix Must Override a Superclass Method Error Eclipse IDE Java | @Override annotation with interface methods

One of the annoying error while overriding Java method in Eclipse IDE is must override a superclass method error, This error is quite frequent when importing Java projects and after so long, still I haven't seen any permanent solution to it. Must override a superclass method the error comes in Eclipse if you have Java Class that implements interface and overrides a method from interface and uses @Override annotation. Unfortunately, Eclipse defaults to Java 1.5, which only recognize @Override annotation for the overriding method from the superclass and not from the interface.

How to fix "No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK" in Eclipse & Maven?

If you are like many Java developer who uses Maven and Eclipse to build Java project using M2Eclipse plugin, you might have seen this error before. I ran into it recently when I ran the Maven Install command for one of the Java projects, configured as Maven project,  only to realize that Maven builds failed after throwing this error. The main reason for this error is that Maven is not able to find javac (the Java compiler) which is required to compile Java source files. If you remember, the javac command comes in the bin directory of JDK, hence, you need a JDK installation in your local machine to compile the Java project.

How to fix java.sql.SQLException: Invalid column index? Example

"java.sql.SQLException: Invalid column index" is a frequent error while working in Java Database Connectivity (JDBC). As the name suggests "Invalid column index" its related to accessing or setting column in your SQL Query using prepared statement in Java. I have seen "java.sql.SQLException: Invalid column index" coming mostly due to two reason:

1) Setting column data using setXXXX(int coloumIndex) e.g. setInt(0) setString(0)

2) Getting column data using getXXX(int columnIndex) e.g. getInt(0) getString(0)

The most common cause of "java.sql.SQLException: Invalid column index" is a misconception that column index started with "0" like array or String index but that's not true instead column index starts with "1" so whenever you try to get or Set column data with column index "0" you will get "java.sql.SQLException: Invalid column index".

How to become Blockchain Architect in 2024? Is Blockchain Architecture Certification by 101 Blockchains worth it?

Blockchain solutions have been making a lot of noise in the tech space recently for all the right reasons. It comes with the advantage of decentralization, security, and transparency. At the same time, you can also notice the possibility of a growing ecosystem of use cases. A Certified Enterprise Blockchain Architect can serve as a promising asset for enterprises in the present times. How? The work of an architect focuses on designing blockchain solutions by evaluating the requirements of the specific use case.

How to learn Metaverse from scratch? Is Certified Metaverse Professional (CMP) on 101 Blockchains worth it

Is Certified Metaverse Professional (CMP) on 101 Blockchains worth it?
Hello guys, if you want to learn Metaverse in 2022 and wondering how to learn Metaverse then you have come to the right place. Earlier, I have shared best Metaverse online courses and in this article, I am going to review one of the popular Metaverse certification, The certified Metaverse Professional certification from 101 Blockchains, one of the leading portal for Blockchain, Web3, NFT, and Metaverse training. The Metaverse is the next big thing, and you must have heard this a million times, just like many tech enthusiasts. The diverse elements of the metaverse have the potential to grab the attention of every person on the planet. Many big companies have already placed their stakes in the metaverse. 

How to use ArrayList in Java? 10 Examples of ArrayList

ArrayList in Java is the most frequently used collection class after HashMap in Java. Java ArrayList represents an automatic re-sizeable array and used in place of the array. Since we can not modify the size of an array after creating it, we prefer to use ArrayList in Java which re-sizes itself automatically once it gets full. ArrayList in Java implements the List interface and allows null. Java ArrayList also maintains the insertion order of elements and allows duplicates opposite to any Set implementation which doesn't allow duplicates. ArrayList supports both the Iterator and ListIterator for iteration but it’s recommended to use ListIterator as it allows the programmer to traverse the list in either direction, modify the list during iteration, and obtain the Iterator's current position in the list.

How to find current directory in Java with Example

Hello guys, if you want to find current directory in Java and looking for a simple example then don't worry. Its easy to get current directory in Java by using built-in system property provided by Java environment. Current directory represent here the directory from where "java" command has launched. you can use "user.dir" system property to find current working directory in Java. This article is in continuation of my earlier post on Java e.g. How to load properties file in Java on XML format or How to parse XML files in Java using DOM parser and Why Java doesn’t support multiple inheritance . If you haven’t read them already, You may find them useful and worth reading. By the way here is a quick example of finding current directory in Java:

How to read from and write to a text file in Java - Example Tutorial

Java has excellent support for reading from file and writing to file in Java. In the last post, we have seen how to create files and directories in Java and now we will see how to read content from files in java and how we will write text into file in Java. File provides a persistent solution to Java developers; in almost every Java application you need to store some of the data in persistent may be its user configuration, system configuration or related to state of the application but without persistence, no enterprise Java application can buildup. 

How to append text into File in Java – FileWriter Example

As a Java developer we often need to append text into File in Java instead of creating a new File, for example log files where every message is written into same file or appended at the end of the file. Thankfully Java File API is very rich and it provides several ways to append text into File in Java. Previously we have seen how to create files and directories in Java and how to read and write to a text file in Java and in this Java IO tutorial we will see how to append text into files in Java. We are going to use the standard FileWriter and  BufferedWriter approach to append text to File. One of the key points to remember while using FileWriter in Java is to initialize FileWriter to append text i.e. writing bytes at the end of the File rather than writing at the beginning of the File.

How to Copy a File in Java Program - Example Tutorial

How to copy files in Java from one directory to another is a common requirement, given that there is no direct method in File API for copying files from one location to another. A painful way of copying files is reading from FileInputStream and writing the same data to FileOutputStream to another directory. Though this process works it's pretty raw to work with and the best approach is for anyone to create a library for common File operations like cut, copy, paste, etc. 

How to read File into String in Java 7, 8 with Example

Many times you want to read contents of a file into String, but, unfortunately, it was not a trivial job in Java, at least not until JDK 1.7. In Java 8, you can read a file into String in just one line of code. Prior to the release of new File IO API, you have to write a lot of boilerplate code e.g. open an input stream, convert that input stream into a Reader, and then wrap that into a BufferedReader and so on. Of course, JDK 1.5's Scanner class did provide some breathing space but it was still not as simple as it should be, like in Python or Ruby. By using Java 7 new File API and Java 8's new features like lambda expression and Stream API, Java is now close to Python or other utility languages, when it comes to reading the file into String.

Top 5 Free and Paid OCAJP, OCPJP Mock Exams and Practice questions - (Java Certification)

In order to do well on Java certifications, you need good books and a reasonable number of practice questions before you go for exams. Practice questions and mock exams will help you to assess your topic-wise preparation level and help you to identify your strong and weak areas. Based on the result of the mock exams, you can concentrate on areas where you lack expertise like multi-threading is one of the tricky areas. It will also expose you to exam patterns and different types of questions you can expect in examination like multiple choice questions, rearranging code, fill in the blanks etc. Though I highly recommend commercial exam simulators like Whizlabs and Enthuware, I also suggest you take advantage of many mock questions which are freely available.

How to read a File in One Line in Java? Files.readAllLines() Example Tutorial

Reading a file in Java is not simple, it requires lots of boilerplate code, as we have seen in our earlier example of reading text files. Various things had to be wrapped e.g. a FileInputStream inside a BufferedReader, loops with weird terminating conditions had to be specified, and so forth. From JDK 7 onward,  you can do a lot better. It provides lots of useful classes like Files and Paths to deal with file and their actual path. In this article, we will see how we can read a file in just one line. Of course, your production code won't be like that, especially if you are reading a few gigabytes into memory and want to pay attention to the character set, if you don't specify, by platform's default character encoding will be used.

Java 8 - Stream FlatMap Example - List of Lists to List

The flatmap is an interesting concept of functional programming which allows you to flatten the list or stream apart from transforming it, just like the map does. This means you can use the flatmap to flatten the stream. If you have used the map() function from the Stream class before then you can use it to convert an object of type T to another object of Type S. For example, if you have a list of Authors then you can convert it to a List of books by transforming authors to books. FlatMap extends this idea, it not only transform one object to other it also flattens the list and that's it's very useful where you want to know about a combined data set. 

How to convert java.util.Date to java.sql.Date - JDBC Example

You often need to convert java.util.Date to java.sql.Date if you are storing dates in a database e.g. SQL SERVER or MySQL. Since JDBC has their own data types for date and time e.g. java.sql.Date, java.sql.Time and java.sql.TimeStamp to match with database date, time and date-time types, you cannot pass a java.util.Date directly. All methods which are supposed to store dates e.g. setDate(paramName, paramValue) expects java.sql.Date, so it becomes essential to know how to convert java.util.Date to java.sql.Date in JDBC. You would be surprised to know that java.sql.Date is a subclass of java.util.Date and all it does is suppress or remove time-related fields from java.util.Date.

How to convert String to Date in Java - SimpleDateFormat Example

Hello Java developers, you may know that SimpleDateFormat in Java can be used to convert String to Date in Java. java.text.SimpleDateFormat is an implementation of DateFormat which defines a date pattern and can convert a particular String that follows that pattern into Date in Java. This is the second part of the article on java.util.Date and String in Java. In the first part, we have seen How to convert Date to String in Java. SimpleDateFormat accepts a String in any date format e.g. yyyyMMdd is a date pattern and  20220924 is a String in that format. Now you want to create a java.util.Date object from this String.

How to Convert Date to String in Java with Example

As a Java developer we often need to convert java.util.Date or LocalDate to String in Java for  displaying purpose or sending Date as String in JSON or XML messages and that's where having a agree upon Date Format is very important. It easily allows you to convert your Date as String and pass between two System. I need it that while working on displaying date in my application and then I thought about this article to list down various way of converting this in various ways after some reading I found that SimpleDateFormat makes this quite easy. 

How to convert Date to LocalDate and LocalDateTime in Java 8 - Example Tutorial

The easiest way to convert a java.util.Date to java.time.LocalDate is via Instant, which is the equivalent class of java.util.Date in JDK 8. You can first convert util Date to Instant and then create a LocalDateTime object from that instant at your default timezone. Once you have an instant of LocalDateTime, you can easily convert that to LocalDate or LocalTime in Java. If you are not living under the rock in the last two years that its 2016 and Java 8 has been around for more than 2 years, 18th March 2014 Java SE 8 GA happened.

17 Examples of Calendar and Date in Java - Tutorial

The java.util.Calendar class was added in Java on JDK 1.4 in an attempt to fix some flaws of the java.util.Date class. It did make some tasks simpler, e.g. create an arbitrary date comes easier using the new GregorianCalendar(2016, Calendar.JUNE, 11) constructor, as opposed to the Date class where the year starts from 1900 and the Month was starting from zero. It didn't solve all the problems like mutability and thread-safety of Date class still remains, but it does make life easier at that time. Now with Java 8 everything related to Date and Time has become super easy and consistent but unfortunately, it will take another 5 to 10 years before the older version of Java goes away. Don't believe me, there are still applications running on JDK 1.5 which was released 12 years ago. The bottom line is it's still important to know about the Date and Calendar in Java.

Review - Is Metaverse Professional Certification on 101 Blockchains worth it?

The metaverse is the next big thing, and you must have heard this a million times, just like many tech enthusiasts. The diverse elements of the metaverse have the potential to grab the attention of every person on the planet. Many big companies have already placed their stakes in the metaverse. Therefore, it is quite clear that a Certified Metaverse Professional certification would be helpful in terms of career development. Interestingly, the opportunities for career development in the metaverse have been doubling in recent times. The following discussion helps you find whether the CMP certification by 101 Blockchains is the best choice in metaverse certifications for you.

10 Difference between Java and JavaScript for Programmers

Programmers, developers, and internet users have always been confused between Java and JavaScript.  Many people still think that JavaScript is part of the Java platform, which is not true. In truth, JavaScript has nothing to do with Java, the only common thing between them is the word "Java", much like in Car and Carpet, or Grape and Grapefruit. JavaScript is a client-side scripting language for HTML, developed by Netscape, Inc, while Java is a programming language, developed by Sun Microsystems. James Gosling is the Inventor of Java, popularly known as the father of Java. 

How to get current URL, parameters and Hash tag using jQuery and JavaScript? Example

While dealing with the current URL, many times you want to know what is the current URL path, What are the parameters, and what is the hashtag on the URL. The hashtag is pretty important if you are implementing a tab structure using HTML and JQuery. To avoid confusion, let's take an example of a URL: http://javarevisited.blogspot.com/2013/01/top-5-java-programming-books-best-good.html#ixzz2PGmDFlPd, in this example ixzz2PGmDFlPd, is a hashtag. Now, both JavaScript and JQuery provide a convenient way to retrieve the current URL in the form of window.location object. You can use various properties of the window.location JavaScript object like the window.location.href to get complete URL, window.location.pathname to get the current path, and window.location.hash to get a hashtag from current URL.

How to format/parse dates with LocalDateTime in Java 8 - Example Tutorial

One of the common tasks in a Java project is formatting or parsing data to String and vice-versa. Parsing date means you have a String that represents a date like "2017-08-3" and you want to convert it into an object which represents the date in Java, like java.util.Date in pre-Java 8 world and LocalDate or LocalDatetime in Java 8 world. Similarly, formatting a date means converting a date instance into a String, for example, you have a Date object or LocalDatetime object and you want a String in dd-MM-yyyy format. Java 8 API provides good support for formatting and parsing dates.

Difference between Period and Duration class in Java 8? [Example]

What is the difference between Period and Duration class in Java is one of the popular Java 8 interview questions and has been asked too many of my readers recently. If you were also wondering the difference between Period vs Duration and when to use Period over Duration and vice-versa then you have come to the right place. Java 8 has two classes to represent differences in time like Duration and Period. The main difference between Period and Duration is that they represent the difference in different units, A Duration is used to calculate time difference using time-based values (seconds, millisecond, or hours) but Period is used to measure the amount of time in date-based values like days, months and year.

What is Double Brace Initialization in Java? Example Initializing HashMap and List with values in Java

Double brace initialization is a Java idiom to initialize a Collection like a list, set, and map at the time of declaration. At times, you need a list of fixed elements e.g. supported products, supported currencies, or some other config, and on-the-spot initialization reduces the line of code and improves readability. Double brace initialization idiom becomes popular because there is no standard way to create and initialize Collection at the same time in Java. Unfortunately, unlike other JVM languages like Scala and Groovy, Java doesn't support collection literals yet. 

3 ways to Learn Redux Framework in depth in 2024 - Best of Lot

The state is a very important part of React development. In simple words, state is a plain JavaScript object that controls the behavior of a React component. If you want to become a professional React developer, then you must understand how to use the state efficiently. React provides inbuilt support for managing state but when the application grows, managing state becomes difficult. So the global state is created for an entire application and to manage such a global state, third-party state management libraries are used.

Top 7 Pluralsight Courses for Data Scientists to Learn in 2024 - Best of Lot

Hello guys, if you are learning Data Science in 2024 and looking for best online courses to learn Data Science and Machine Learning or got a Pluralsight membership but are not sure which Pluralsight courses to join to better your Python, Data Science, Data Visualization, and other data-related skills then you have come to the right place. Earlier, I have shared the best Pluralsight courses to learn Java, Python, React.js, and JavaScript and today, I am going to share the best Pluralsight courses for Data Science and Data Scientists. These are my favorite Pluralsight courses on the topic as well and even if you are just starting with Data Science you can join these courses to learn a lot. 

Top 10 LinkedIn Learning Courses for Java and Web Developers in 2024 - Best of Lot

Hello guys, if you want to learn Java and Spring Framework in 2024 and are looking for the best LinkedIn learning online courses, you have come to the right place. Earlier, I shared the best Java and Spring Framework courses from Udemy, Coursera, and Pluralsight. This article will find the best Java, Spring, Spring Boot, and Microservices courses for Java developers.  LinkedIn Learning is an educational website by popular social networking site LinkedIn, where I think every Java developer should have their account. It has a lot of practical courses to learn essential skills and technology, and today, I will share the best LinkedIn Learning courses for Java and Spring Boot developers.

Right way to Close InputStream and OutputStream in Java - Example

For some unknown reasons many Java programmers are not very comfortable with IO package. I don't know why, but I have found them much more comfortable with java.lang and java.util than java.io. One possible reason of this could be that, writing IO code require a bit of C++ like programming, which involves doing clean-up, releasing resources once done etc. Since Java made coding a lot easier by taking care of memory management, unknowingly it also introduced bad practice of not releasing resource after use like database connections, socket connection, files, directory, printers, scanners or any other scarce resource.

How to Learn Python Programming in 2024?

Hello guys, if you want to learn Python Programming language in 2024, one of the most popular programming language of this time but are not sure where to start then you have come to the right place. In the past, I have shared many Python resources like best Python Books, Courses, Projects, interview questions, and even best places to learn Python and  In this article, I am going to share with you the 3 best ways to learn Python programming from scratch. These are my tried and tested way to master any programming language or Framework and I have used this to learn Java, Python, JavaScript and many other technology. 

Top 10 Python Courses on Pluralsight for Beginners and Experienced Developers - Best of Lot

Hello guys, if you want to learn Python Programming language in 2022 and looking for the best Python online courses on Pluralsight then you have come to the right place. Earlier, I have shared the best Python books, Python 3 courses, and Python websites to learn Python programming and in this article, I am going to share the best Python courses from Pluralsight. If you don't know Pluralsight is a leading online learning platform where you get a chance to learn from expert trainers. They are known for their high-quality courses and they have more than 7500+ courses. They also have many projects and hands-on exercises and you can get access to them with just one Pluralsight membership. 

Top 5 Platforms to learn NFT (Non Fungible Tokens) in 2024 - Best of Lot

Hello guys, if you want to learn Non Fungible tokens or NFT in 2024 and looking for best resources then you have come to the right place. Earlier, I have shared best paid NFT courses and best free NFT courses and in this article, I am going to share best places to learn NFT in 2024. To be honest, It's hard to find good NFT training courses and certifications on sea of resources on internet this article tells best platforms to learn NFT and become a NFT professionals in 2024. The constantly rising fame of non-fungible tokens has induced waves of transformation across various sectors. More and more people are interested in learning more about NFTs and exploring their potential.

Top 10 Courses to Learn Metaverse online in 2024 - Best of Lot

Hello guys, if you want to learn about Metaverse and looking for best online courses then you have come to the right place. Metaverse, Web3, and NFT are three buzz words and latest tech which is dominating  internet at the moment. Earlier, I have shared best NFT online courses and in this article I am going to share best Metaverse online courses for beginners to learn in 2024.  But, before we get to the 10 best courses that you can use to learn everything you need to know about Metaverse, let me tell you what it really is.

101 Blockchains Review - Is Enterprise Blockchain Professional Certification worth it? [CEBP]

Hello guys, last year, I was looking for a comprehensive Blockchain Certification when I stumble upon Certified Enterprise Blockchain Professional (CEBP) by 101 Blockchins.com, a site dedicate to teach you Blockchain, NFT, Metaverse, and Web3 skills. This was the Blockchain course I was looking from start as the most of the courses I found are either too shallow or too much technical that you will start feeling sleepy from first lecture. This Blockchain course was just right. It not only covers everything you need to know about Blockchain technology but also cover them in engaging and detailed way. When I first mention this course on my list of best Blockchain certifications and courses, a lot of you asked me to publish a detailed review of this course and here we are. 

How to implement Command Design Pattern in Java with Example

Hello guys, it's been a long since I have shared a Java design pattern tutorial. I did share some courses to learn design patterns but haven't really talked about a particular design pattern in depth. So, today, we'll learn one of the important design pattern, which is often overlooked by Java developers. Yes, I am talking about the Command Pattern which can help you write flexible, loosely coupled code for implementing actions and events in your application. In simple words, the command design pattern is used to separate a request for action from the object which actually performs the action. This decoupling between Invoker and Receiver objects provides a uniform way to perform different types of actions. This decoupling is achieved using a Command object, which is usually an interface with methods like execute(). 

Can a Non Static Method Access a Static Variable/Method in Java?

"Can a non-static method access a static variable or call a static method" is one of the frequently asked questions on the static modifier in Java, the answer is, Yes, a non-static method can access a static variable or call a static method in Java. There is no problem with that because of static members i.e. both static variable and static methods belong to a class and can be called from anywhere, depending upon their access modifier. For example, if a static variable is private then it can only be accessed from the class itself, but you can access a public static variable from anywhere.

How to create Tabs UI using HTML, CSS, jQuery, JSP and JavaScript? Example

JSP is still a popular technology for developing view part of Struts and Spring-based Java applications, but unfortunately, it doesn't have rich UI support available in GWT, or any other library. On another day, we had a requirement to display HTML tables inside tabs, basically, we had two tables of different data set and we need to display them in their own tabs. Users can navigate from one tab to another, and CSS should take care of which tab is currently selected, by highlighting the active tab. Like many Java developers, our hands-on HTML, CSS, and JavaScript are a little bit tight than a web guy, and since our application is not using any UI framework, we had to rely on JSP to do this job.

How to use Adapter Design Pattern in Java with Example

The adapter design pattern in Java, also known as the Wrapper pattern is another very useful GOF pattern, which helps to bridge the gap between two classes in Java. As per the list of Gang of Four patterns, the Adapter is a structural pattern, much like Proxy, Flyweight, Facade, and Decorator patterns in Java. As the name suggests, the Adapter allows two classes of a different interface to work together, without changing any code on either side. You can view the Adapter pattern as a central piece of the puzzle, which joins two pieces, which can not be directly joined because of different interfaces.

java.lang.UnsatisfiedLinkError: no dll in java.library.path - Cause and Solution

"Exception in thread "main" java.lang.UnsatisfiedLinkError: no dll in java.library.path" is one of the frustrating errors you will get if your application is using native libraries like the DLL in Windows or .SO files in Linux. Java loads native libraries at runtime from either PATH environment variable or location specified by java.library.path system property depending upon whether your Java program is using System.load() or java.lang.System.loadLibarray() method to load native libraries. If Java doesn't find them due to any reason it throws "java.lang.UnsatisfiedLinkError: no dll in java.library.path". 

Spring Boot Error - Error creating a bean with name 'dataSource' defined in class path resource DataSourceAutoConfiguration

Hello guys, If you are using Spring Boot and getting errors like "Cannot determine embedded database driver class for database type NONE" or "Error creating a bean with name 'dataSource' defined in class path resource ataSourceAutoConfiguration" then you have come to the right place. In this article, we'll examine different scenarios on which this Spring Boot error comes and what you can do to solve them. The general reason for this error is Spring Boot's auto-configuration, which is trying to automatically configure a DataSource for you but doesn't have enough information. It is automatically trying to create an instance of DataSourceAutoConfiguration bean and it's failing.

Difference between WHERE vs HAVING clause in SQL - GROUP BY Comparison with Example

What is the difference between WHERE and  HAVING clause in SQL is one of the most popular questions asked on SQL and database interviews, especially to beginners? Since programming jobs, required more than one skill, it’s quite common to see a couple of SQL Interview questions in Java and .NET interviews. By the way unlike any other question, not many Java programmers or dot net developers, who are supposed to have knowledge of basic SQL, fail to answer this question. Though almost half of the programmer says that WHERE is used in any SELECT query, while HAVING clause is only used in SELECT queries, which contains aggregate function or group by clause, which is correct.

Top 5 Software Platforms to Create and Sell Online Courses in 2024 - Best of Lot

Hello guys, if you are an online course creator, instructor, or blogger looking for best software and online platform to create, and sell your online courses then you have come to the right place. In the past, I have how shown you how to create online course for FREE and In this article, I am going to share the best software to create and sell your online training courses. You will learn about the best online teaching Software and platforms like Teachable, Thinkific, Udemy, and Podia and analyze them to find out which is best software for creating and selling online courses. Online Course business is becoming bigger and bigger with so many bloggers, professionals, programmers are creating online courses and making good money. It's a new avenue for passive income creators and I think it's one of the best I know. Why? because it's a win-win for everybody.

How to Create Online Course for FREE? Best Tools, Software and Platforms

Hello guys, I have been telling my readers and fellow programmers to create an online course in 2022, and many of them have already started planning their courses. Though, one question which keeps coming to me is how you can create an online course for free? This is an obvious question, and after answering many of my readers over Facebook chats and emails, I decided to write a blog post about it so that everyone else who wants to create an online course for free can create and sell online courses for free without any investment except time and passion can benefit. But, before answering this question, let me first congratulate you on making an excellent decision to create an online course, the best win-win situation where everybody involved in this process wins.

Top 6 Websites to learn Blockchain for FREE in 2024 - Best of Lot

Hello guys, if you want to learn Blockchain in 2024 and looking for best website to learn Blockchain for FREE then you have come to the right place. In the past, I have shared best Blockchain books, best Blockchain course, and best Blockchain certification, and in this article, I am going to share best places to learn Blockchain for FREE. Blockchain is a newbie technology that is gaining popularity in the marketplace. If you wish to pursue a career in this field, you must first get a thorough understanding of blockchain technology. Online certification courses can equip you with both academic and practical understanding since it is a sophisticated and relatively new technology.

Top 10 Pluralsight Courses for Cyber Security Professionals in 2024 - Best of Lot

Hello guys if you are looking for best Pluralsight courses to learn Cyber Security and Information Security in 2024 then you have come to the right place. In the past, I have shared best Cyber Security Courses and best Ethical Hacking Courses and today, I am going to share best Pluralsight courses for Cyber Security Professionals in 2024. The list includes courses to learn Cyber Security from scratch and in depth. I have specially included courses on important Cyber Security topics and tools like Malware detection and prevention. You can also use this list as a reference and learn the skills you need and become a better Cyber Security Professional in 2024.

Top 10 Essential Skills to become a Better Data Scientist in 2024

Hello guys, if you want to become a Data Scientist but not sure which skills to learn then you have come to the right place. Earlier, I have shared best Data Science courses, tutorials, books, and best sites to learn Data Science online, and in this article, I will share essentials skills you can learn to become a successful Data Scientist in 2024. Since just knowing the skill is not enough, I have also shared relevant courses to learn those skills from Udemy, Coursera, Pluralsight and other popular online learning portals, as its more important to learn those skills rather than just knowing it. It's more likely that you already know many of them like Mathematics, Statistics, SQL, and Problem Solving but knowing where to go to refresh and hone those skills can help you to become better. 

5 Best Programming Languages To Start Your Career in Software Development and Best Courses To Learn Them

Hello guys, If you want to become a Programmer or Software developer in 2022, you should be an expert in not one, but multiple programming languages. It is an absolute necessity to be skilled and fluent in more than one programming language. But which programming languages should you master, you might be asking. Well, don't worry. We have got your back.  Gone are the time when you can just learn one programming language like Python, Java, or JavaScript and done, nowadays every job demands more and there is always a couple of programming language you can find in job description.

How to Set Classpath for Java on Windows and Linux? Steps and Example

What is CLASSPATH in Java? Classpath in Java is the path to the directory or list of the directory which is used by ClassLoaders to find and load classes in the Java program. Classpath can be specified using CLASSPATH environment variable which is case insensitive, -cp or -classpath command-line option or Class-Path attribute in manifest.mf file inside the JAR file in Java.  In this Java tutorial, we will learn What is Classpath in Java, how Java resolves classpath and how Classpath works in Java alongside How to set the classpath for Java in Windows and UNIX environment. 

Difference between Direct, Non Direct and Mapped ByteBuffer in Java?

ByteBuffer is one of the important classes of Java NIO API. It was introduced in java.nio package on JDK 1.4, it not only allows you to operate on heap byte arrays but also with direct memory, which resides outside the JVM. There are mainly three types of ByteBuffer in Java - Direct Byte Buffer, Non-Direct ByteBuffer, and mapped byte buffers. You can create both direct and non-direct buffers using java.nio.ByteBuffer class, while MappedByteBuffer is a subclass of ByteBuffer, which is created by FileChannel.map() method, to operate on memory-mapped file. 

String vs StringBuffer vs StringBuilder in Java? Example

Difference between String, StringBuffer, and StringBuilder

The String is one of the most important classes in Java and anyone who starts with Java programming uses String to print something on the console by using famous System.out.println() statements. Many Java beginners are not aware that String is immutable and final in Java and every modification in String creates a new String object. For example, when you get the substring, you get a new String, when you convert uppercase String to lowercase, a new String is created. Even when you remove space by calling the trim() method, a new String is returned. 

Java 8 forEach() Loop Example

Java 8 has introduced a new way to loop over a List or Collection, by using the forEach() method of the new Stream class. You can iterate over any Collection like List, Set, or Map by converting them into a java.util.sttream.Stream instance and then calling the forEach() method. This method performs given operation on every element of Stream, which can be either simply printing it or doing something else. Since stream can be sequential or parallel, the behavior of if this method is not deterministic if used with a parallel stream. 

Difference between Transient, Persistent, and Detached Objects in Hibernate

In the Hibernate framework, an entity can be in three states, transient, persistent, and detached. When an object is in a transient state, it is commonly referred to as a transient object, similarly, if it is in persistence and detached state, it is known as a persistent and detached object. When an entity is first created using the new operator like new User() and not associated with Hibernate session like you haven't called session.save(user) method then it is known as a transient object. At this stage, Hibernate doesn't know anything about this object and the object doesn't have any representation in the database like a corresponding row in the User table.

How to use filter + map + collect + Stream in Java? Example Tutorial

Hello guys, many of my readers emailed me to write a post about the map and filter function of Java 8 because they found it difficult to understand and use. Even though I have previously blogged about both map() and filter(), I am writing this post again to explain the concept in more layman's language for a better understanding of my readers and fellow Java developers. The map() function is a method in Stream class that represents a functional programming concept. In simple words, the map() is used to transform one object into another by applying a function. That's the reason the Stream.map(Function mapper) takes a function as an argument. For example, by using map() function, you can convert a list of String into List of Integer by applying Integer.valueOf() method to each String on the input list.

Top 5 Free Pandas Courses for Beginners to learn Data Analysis in 2024 - Best of Lot

Hello guys, if you want to learn Pandas library, one o the most popular Python library for Data Scientists and Machine Learning engineers and looking for the best resources like online courses, books, tutorials, and training classes then you have come to the right place. Earlier, I have shared the best Pandas for Data Analysis courses and in this article, I am going to share free Pandas courses for beginners to learn in 2024. Many developers switched to learning python programming language due to its variety of libraries that offer developers, like creating web apps using Django.

How to prepare for AWS certified Advanced Networking Specialty Exam in 2024

Hello guys, if you are preparing for AWS Advanced Networking Specialty Certification in 2024 but not sure how to prepare for this exam then you have come to the right place. In the past, I have shared several AWS courses and Practice tests for different AWS Certifications like AWS Developer, AWS Solution Architect Associate, and AWS SysOps and in this article, I am going to share best resources and step by step guide to prepare for AWS Networking Specialty exam. Certification in AWS services and hybrid IT network designs may be shown by passing an exam such as the AWS Certified Advanced Networking Specialty test. This is not a beginner's exam, but rather a test for those who are already proficient in using AWS to do difficult networking tasks.

Top 50 SQL and Database Phone Interview Questions Answers

Database and SQL is a very important skill, not just for DBA or Database admins but also for any application developer like Java, .NET, or Web developers. This is why you would often see questions from SQL and Database in Programming interviews. For DBAs, SQL is more important than a programmer, because it being their primary skill, they are also expected to know more than a common Java or .NET developer. Since no Java interview is just about Java questions, many times I receive a request from my reader about SQL questions like how to solve a particular query or some tricky questions based upon database indexes.

How to use Environment Variables in Spring Boot's application.properties file? Example Tutorial

How to use environment variable in Spring boot's application.properties is a major problem when your spring boot application running on different places like local, Jenkins, and OpenShift. So we need to make the data source file dynamic in the application.properties file. So let's have look at how to do this at how to use the env variable in Spring Boot's application.properties. So in this tutorial, We assume that you have knowledge of Spring boot and not going to talk about small details. 

Top 5 Courses to Learn F# (F Sharp) for Beginners in 2024 - Best of Lot

For those who are new here, F# also called F sharp, is a functional programming language that allows you to solve complex problems by writing simple pieces of code.  F# makes it very easy to write concise code that can solve complex problems. It is a functional programming language like Scala, Haskell, Elixir, and Erlang. The best thing about F# programming language is that its available on all the major desktop and mobile platforms. F# is built on the .NET framework and offers good interoperability, portability, and speed. It also offers conciseness, convenience, correctness, concurrency, and completeness. 

Top 10 Pluralsight Courses to Learn Cloud Computing in 2024 - Best of Lot

Hello guys, if you are looking for best Pluralsight course to learn Cloud Computing in 2024 then you have come to the right place. In the past, I have shared best Pluralsight courses for Java Developers, and best Pluralsight courses to learn JavaScript, React.js, and Cyber Security and today, I am going to share with you best Cloud computing courses from Pluralsight. If you have Pluralsight membership, monthly, yearly or premium or from your company then these are truly the best resources to start with Cloud computing in 2024. But, before we get to the 10 best courses that will teach you all about cloud computing, let me tell you what the term cloud computing actually means.

Top 5 Courses for AWS Advanced Networking Specialty Exam in 2024 - Best of Lot

Before I tell you about the best courses that you can use to pass the AWS Advanced Networking Specialty Exam, let me tell you what exactly it is, right? It is basically a certification that allows organizations to identify and develop talent with critical skills for implementing cloud initiatives. If you earn the AWS Advanced Networking Specialty Certification, it means that you are an expert in designing and maintaining network architecture for a variety of AWS services. The AWS Certified Advanced Networking Specialty Exam is meant for individuals who perform complex networking tasks with five years of hands-on experience architecting and implementing network solutions. 

Top 5 Courses to Crack AWS Database Specialty (DBS-C01) Exam in 2026 - Best of Lot

Before I tell you about the Best Courses for the AWS Database Specialty exam, let me tell you what it exactly is. It is basically a certification that allows companies to identify and develop talent with critical skills for implementing cloud initiatives. If you earn an AWS Certified Database Specialty, it means that you are an expert in recommending, designing, and maintaining optimal AWS database solutions. The AWS Certified Database Specialty exam is meant for individuals with experience and expertise working with on-premises and AWS CLoud-based relational and non-relational databases.