Why non-static variable cannot be referenced from a static context? Example

"non-static variable cannot be referenced from a static context" is the biggest nemesis of someone who has just started programming and that too in Java. Since the main method in java is the most popular method among all beginners and they try to put program code there they face "non-static variable cannot be referenced from a static context" compiler error when they try to access a non-static member variable inside the main in Java which is static. if you want to know why the main is declared static in Java see the link.

Top 5 Java Forums for Programmers and Developers

When you face a Java problem where do you go? StackOverflow, Coderanch, or Official Java forums? Yes, there are lots of online resources to help a Java programmer when he is stuck. Being one of the most popular programming languages ever, Java has a huge community. There are lots of blogs, websites, and forums to help you with the minute detail of Java programming. It doesn't matter if you are a beginner facing a problem or an expert looking for the best possible way to do certain things in Java, forums always provide good support.

How to find if JVM is 32 or 64 bit from Java program? Example

You can find JVM bit sizes like 32 bit or 64 bit by using either running java command from the command prompt or by using System.getProperty() from Java program. The question is why do you want to know hardware or platform configuration while writing Java code which is supposed to write once and read anywhere(32 bit, 64 bit, etc)? Yes we don't really need to know whether JVM is 32 bit or 64 bit more often but there are many situations when this matters

Java Best Practices for Method Overloading? Examples

You need to be careful while overloading a method in Java, especially after the introduction of autoboxing in Java 5. Poorly overloaded method not only adds confusion among developers who use that but also they are error-prone and leaves your program at compiler's mercy to select proper method. One of the best examples of a poorly overloaded method is the removal method of ArrayList. There are two versions of remove, first, one which takes an Object as argument i.e. remove(Object element), and the second one, which takes an index as argument i.e. remove(int index).

How to take array input from command line in Java ? Scanner Example

There is no direct way to take array input in Java using Scanner or any other utility, but it's pretty easy to achieve the same by using standard Scanner methods and asking some questions to the user. For example, if you want to take a one-dimensional array of String as input then you can first ask the user about the length of the array and then you can use a for loop to retrieve that many elements from the user and store them in an array. You can use the next() to take a String input from the user. Similarly, if you need to take an integer array or double array, you can use the nextInt() or nextDouble() method of the Scanner class.

Top 10 FIX Message Interview Questions Answers for Beginners

FIX (financial information exchange) protocol is the global protocol used for Electronic trading of different asset classes e.g Equity, Fixed Income FX (foreign exchange) , Derivatives Futures and Options and its knowledge is essential to understand Electronic trading and FIX messages. I have listed some of the very common but informative questions asked in FIX protocol interview question, this list is by no means complete and only contains questions on top of my mind, I would encourage reader to post any question they have been asked and I will include on this list.

How to view FIX Messages in a Readable format? Free Online FIX Message Viewer Tool

It's been a long time, I wrote anything related to FIX protocol, my last article was about FIX protocol dictionaries, also known as Fixionnary, one of the most important tools of the trade for Java developers and support personnel working in FIX. Today, I am going to share another useful tool called FIX Log Viewer, which allows you to view FIX engine logs in a much more readable format.

How to use String.codepoint() method in Java? Example Tutorial

CodePoint method in String is used to get Unicode code point value at index or before the index.  In String class we have a lot of utility methods for dealing with String like Split, replace, and SubString method but here I am discussing a relatively lesser-known method codePointAt(), codePointCount(), and codePointBefore(), but before going deep about this method lets first understand what is of the code point, what exactly CodePoint method does and how to use CodePointAt, CodePointBefore methods using java code example.

Codecademy Learn Java Review - A Free Java Course to Learn Coding Online

Hello guys, you may not know but Codecademy has a free Java course that is perfect for beginners, almost 2.3 million students have already registered. Does it say anything about the popularity of Java? Given Java provides a really good prospect of getting a job and there is more than one reason to learn Java, I am not surprised by the number of students registered. Codecademy has always been a superb source to learn new programming languages or technology from the start. I first started using Codecademy for learning JavaScript using their free JavaScript course and then I used it a couple of months back to improve my Python and Linux command skills.

Top 8 Python Libraries for Data Science and Machine Learning - Best of Lot

Hello guys, today I am going to talk about something which is not related to Java but a very interesting technology development that is happening around, and you simply can't afford to miss out on this opportunity. Yes, you guessed it right, I am talking about Machine learning, Artificial Intelligence, and Deep Learning. There is a good chance that you might have already heard about them and even started learning them. You may be either from Python camp or learning R programming for the sake of machine learning. When I started my journey of Machine learning and Data Science, I had to first make a choice about choosing the right programming language as both R and Python were doing great.

How to increase length of existing VARCHAR column in SQL Server? Example Tutorial

You can increase the length of a VARCHAR column without losing existing data in SQL Server. All you need to do is execute the following ALTER TABLE statements. Though, you need to specify NULL or NOT NULL constraint explicitly, depending upon your data.

Here is the SQL command you can use to increase the length of a VARCHAR column in SQL Server:

ALTER TABLE Books ALTER COLUMN title VARCHAR (432)

This command increases the length of the title column of the Books table to 432 characters. You can use the same command to increase the length of CHAR, NCHAR, or NVARCHAR columns as well.

Top 10 Computer Programming, Artificial Intelligence, and Sci-Fi Movies for Programmers and Tech geeks

Hello guys, being a computer programmer, I love movies that are based on programmers' life, work, and concept. Thankfully Hollywood is no short of films based on computers, programming, and geeky technical stuff. Another day, I was pretty bored, and when I look back to my DVD collection, I found Inception, Matrix Reloaded, and The Social Network, this all movies are in some way related to computers and technology, which strike me the idea to publish my list of Top 10 Computer programming movies.

How to Crack Spring Professional Develop (2V0-72.22) Exam - Latest Spring Certification for Java Programmers

Ever since VmWare, the company behind the Spring framework made the mandatory Spring training optional (see here), I have received many queries from experienced Java developers who are interested in doing Spring certifications. This move from VmWare has suddenly made the Spring certification affordable for many experienced Java and Spring developers who were interested in Spring certification earlier but couldn't progress further due to expensive mandatory training. Since many of them are now preparing for Spring certifications like Spring Core  or Spring Professional (VMware EDU-1202) via self-study they are increasingly looking for good resources to prepare for the exam. I have received a lot of questions on preparation, books, mock exams, exam structure, passing marks, and useful resources.

Top 10 Advanced C++ (CPP) Books for Experienced Developers - Must Read

Once you know C++ and spends a couple of years of programming in C++, you started to feel that you know the basics and have good command over C++ programming. At this time, the programmer goes to two paths, one who chose to do just fire-fighting and daily work and never upgraded or forced to learn new or more by reading books, participating in forums, and giving presentations. The other group of programmers explores new books to learn C++ in detail and after reading a couple of books on this list, they also realize how much of C++ they know is incomplete and incorrect. That's why I recommend experienced C++ developers to read books to complete the journey from a junior developer to a senior developer.

Top 3 Books to Learn TCP/IP, UDP and Computer Networking Protocols - Best of Lot

Both TCP/IP and UDP are very popular networking protocol and in this era of the internet and a connected world, they become even more important. No matter, whether you are a computer science graduate or doing masters in computer science, a software engineer, a network engineer, or a Java programmer, good knowledge of TCP/IP and UDP goes a long way to securing a job and doing well on it. Even though I mostly interview for Java programmers, I almost always ask a couple of questions on TCP/IP and UDP protocol to check if the candidate is familiar with computer network basics or not because even if you work for Java application, you are exposed to the network.