Annotation is code about the code, that is metadata about the program itself. In other words, organized data about the code, embedded within the code itself. It can be parsed by the compiler, annotation processing tools and can also be made available at run-time too. We have basic java comments infrastructure using which we add [...]
Thought of compiling a list of classes that are popular among java programmers. Should I say most essential? There is no strict rules for the selection, in fact there are no rules followed. Classes that popped up on top of mind are listed below. You are welcome to add your own list. This list will [...]
When there is a need to trigger a task automatically based on time we should schedule it using a timer api. The requirement can vary from a single execution on a fixed time to high complex recurring event. For example take our regular alarm clock where we fix a time and it beeps coming day [...]
It is love at first type. I fell in deep love with it from the first moment I used it. Didn’t you? How many times have we used it till now? It is one of the most number of times compiled statement in the history of java. We fondly call it SOP. If you want [...]
Core concept of ThreadLocal is, “every thread that accesses a ThreadLocal variable via its get or set method has its own, independently initialized copy of the variable”. In other words, we want to have separate instances(private copy) of a class so that there will not be any conflict among multiple threads. Each instance will be [...]
To generate successive elements from a series, we can use java iterator. It is an improvement over Enumeration interface. Iterator takes the place of Enumeration since jdk 1.2 It is a nice utility for collections. Every collection is unique on its own and imagine if we have have to write logic on our own for [...]
Semaphore is an interesting topic in operating systems and it can be used in a variety of ways to solve challenging problems. In this article I will explain, what is a semaphore how to implement a semaphore in java an example problem and solution implementation using semaphore. Following is a challenging programming problem we have [...]
Editors are an integral part of a programmer’s life. If you have good proficiency in using an editor thats a great advantage. It comes very handy to debug. Traditional notepad and SOPs (System.out.println) are the way we start learning a language but that is not sufficient, so beginners start using an IDE and most importantly [...]
Java ClassLoader loads a java class file into java virtual machine. It is as simple as that. It is not a huge complicated concept to learn and every java developer must know about the java class loaders and how it works. Like NullPointerException, one exception that is very popular is ClassNotFoundException. At least in your [...]
