Thursday, 21 September 2017

Producer Consumer Solution using BlockingQueue in Java

Producer Consumer problem is one of the classic multi-threading problems in computer science and the multi-threading world. It's tricky because it involves inter-thread communication, but it's important because most of the multi-threading problems fits into this category. There are many ways to solve producer consumer problem in Java e.g. you can solve this by using wait() and notify() method, as discussed here, or you can use the Semaphore to solve this problem. In this article, you will learn a third way to solve the producer-consumer problem by using the BlockingQueue in Java. It is arguably the simplest way to solve this problem in any programming language because blocking queue data structure not only provides storage but also provides flow control and thread-safety, which makes the code really simple. Brian Goetz has also explained this key class and pattern in his classic Java Concurrency in Practice book, a must read for serious Java developers.

Tuesday, 19 September 2017

Java 9, Jigsaw, JPMS, and Modules: A Personal Exploration

Java 9 delayed so many times because of Project Jigsaw, and you may be heard a lot of thing about modules, modularity, and other stuff, so, what it’s all about? What the heck is modularization and what do we mean by modularized platform? Java Platform Module System (JPMS)? Is it going to be a revolution in Java ecosystem?

This post is my exploration of the most important thing that happened to the JDK, the Module System. I will explain what modularization is, why you need it, and how you can create your modularized project.

Monday, 18 September 2017

Java Application Performance Monitoring: End-to-end performance of complex distributed applications

Monitor Java application performance — focused on business transactions — end-to-end in the most complex and distributed environments. Auto-discovered business transactions, dynamic baselining, code-level diagnostics, and Virtual War Room collaboration ensure rapid issue identification and resolution to maintain an ideal user experience for any Java application, running on-premises or in cloud. Get real-time visibility into how your applications perform inside many of the industry-leading Java application servers, including Weblogic, WebSphere, JBoss, Tomcat, Glassfish and more.

Tuesday, 12 September 2017

How to find highest repeating word from a text File in Java - Word Count Problem

How to find the word and their count from a text file is another frequently asked coding question from Java interviews. The logic to solve this problem is similar to what we have seen in how to find duplicate words in a String. In the first step you need to build a word Map by reading contents of a text File. This Map should contain word as a key and their count as value. Once you have this Map ready, you can simply sort the Map based upon values. If you don't know how to sort a Map on values, see this tutorial first. It will teach you by sorting HashMap on values. Now getting key and value in sorted should be easy, but remember HashMap doesn't maintain order, so you need to use a List to keep the entry in sorted order. Once you got this list, you can simply loop over the list and print each key and value from the entry. This way, you can also create a table of words and their count in decreasing order.  This problem is sometimes also asked as to print all word and their count in tabular format.

Monday, 11 September 2017

How to enable/disable an element using jQuery and JavaScript?

Sometimes we need to enable and disable input elements e.g. text box, radio buttons or checkbox, how can we do it dynamically without loading the page? Well, we can use JavaScript, particularly jQuery to do this. An element can be disabled in HTML by setting disable property to true and enabled again by setting disabled=false. By using jQuery, we can grab the element we want to enable or disable and change this property by using prop() or attr() function, depending upon which version of jQuery you are using. prop() function was added in jQuery 1.6 and its the standard way to deal with properties but attr() function does the same job for jQuery 1.5 and lower version so you can use attr() for the same purpose in jQuery version lower than 1.6.