15 People Java Developers Should Follow on Twitter

If you are passionate about Java and would like to follow Java bloggers into Twitter then here is my list of 15 people you can follow on Twitter to keep yourself up-to-date and engage in Java world. These people regularly share the latest things in Java, JVM, Spring, Hibernate, and other Java technology. By following them, you will not only know about their latest work but also what's happening in Java world. You might be thinking just 15 people, well, there are many more which is not in this list but I regularly share their twitter handles via my twitter account @javinpaul and @Javarevisited. If you are following me then you will automatically get to know about them.

How to solve Arithmetic overflow error converting IDENTITY to data type tinyint, smallint or int in Microsoft SQL Server database

Last year we had a production issue where one of our backup jobs was failing while inserting Orders aggregated from other systems into our SQL Server database. The reason was dreaded "Arithmetic overflow error converting IDENTITY to data type int" because the table was using IDENTITY feature of SQL Server to generate OrderId, and Identity has breached it a maximum value, which is around 2.1 billion, precisely 2,147,483,647. The error "Arithmetic overflow error converting IDENTITY to data type int" comes when IDENTITY value is inserted into a column of data type int, but the value is out-of-range. For example, if the current value of Identity becomes more than 2,147,483,647, then you cannot store that into an int column because it's more than the maximum value of int in SQL Server.

How to Prepare for Java Certifications like OCAJP, OCPJP, or OCEJWCD?

No doubt that Oracle's Java certification is one of the most valuable certifications for IT industry and helps you to get a better job, better pay, and a better rise in your current salary. It also improves your recognition and job prospects because many big clients demands certified Java programmers for their mission-critical applications. Because of enormous popularity and usefulness, many Java developers and computer science graduate aspire for Java certifications. I often receive queries like, what is the best way to prepare for Java certifications like OCAJP or OCPJP? Or I am already coding in Java, do I need to make explicitly for this exam to do well or my Java development experience is enough? I have 5 years of experience in Java, do I need to prepare for OCAJP 8 or OCPJP 8 exam? Etc.

3 ways to create random numbers in a range in Java

Many times you need to generate random numbers, particular integers in a range but unfortunately, JDK doesn't provide a simple method like nextIntegerBetween(int minInclusive, int maxExclusive), because of that many Java programmers, particularly beginners struggle to generate random numbers between a range, e.g., random integers between 1 to 6 if you are creating a game of dice, or random number between 1 to 52 if you are creating a game of playing cards, and you need to choose a random card, or most commonly random numbers between 1 to 10 and 1 to 100. Then, the question comes, how to solve this problem? How to generate random int values between a range? Well, you need to do a little bit of work.

How to Convert a List or Set of String to Comma Separated String (CSV) in Java 8

Before Java 8, it was not straightforward to convert a list of String to a comma-separated String. You have to loop through the collection or list and join them manually using String concatenation, which can take up more than 4 lines of code. Of course, you could encapsulate that into your own utility method and you should but JDK didn't provide anything useful for such a common operation. Btw, things have changed. From Java 8 onwards you can do this easily. JDK 8 has provided a utility class called StringJoiner as well as added a join() method into String class to convert a List, Set, Collection or even array of String objects to a comma separated String in Java.