Core java

In this post, we will see about Inheritance in java. It is one of the OOPs principles apart from Abstraction, encapsulation and polymorphism. Introduction The word Inheritance is quite familiar with everyone. In common terms, the word means the bequeathing of property and characteristics from generation to generation. For example, the property or characteristics of […]

Java is one of the most used programming languages in the world for developing the desktop application and web application.It has completed 22 years in the programming world. In this post, we will see how to learn java programming in depth and in most efficient way. Java has a huge learning curve, it is a […]

Java 5 has introduced new framework called Executor Framework for managing threads.We have already seen before how to create a thread. If you have noted, we need to create an object of thread class using new Thread(runnableObject), so we need to create thread object for each task.Imagine a situation where you have thousands of task […]

In this tutorial, we will see Java interview programs for logic building. These java programs will help students to crack Java interview. Here is the list of Top 10 Java interview programs for logic building. Question 1: Check if number is odd or even? Answer: It is a very basic question. You need to check […]

In this post, we will see about Java ExecutorCompletionService example. ExecutorCompletionService class implements CompletionService. This class returns Future object in completion order. Why you may need to use ExecutorCompletionService: Let’s understand with the help of scenario: Let’s say you have 5 tasks, you submit it to the executors and you want to perform some operation as soon […]

In this tutorial, we will see how to find length/size of Arraylist in java. You can use ArrayList’size() method to calculate size of ArrayList. Let’s understand it with the help of Simple example. [crayon-67480bd82f0fe436799550/] When you run above program, you will get below output: Size of Country List is: 4 [India, China, Bhutan, Nepal] Size […]

In this tutorial, we will learn about Executor’s newSingleThreadExecutor factory method. In the last tutorial, I have shared an introduction to ThreadPoolExecutor. If you are not aware of concepts of ThreadPoolExecutor, you should go through that first. Executor’s newSingleThreadExecutor factory method : This method returns thread pool executor which executes one task at a time.If […]

There are multiple ways to schedule a task in java. We have already Java timer to schedule a task but the problem with timers task is that you can execute one task at a time.So if the current task takes longer subsequent job will be delayed. In this scenario, you can use Java ScheduledThreadPoolExecutor.This class […]

In this tutorial, we will see about Java FutureTask example. FutureTask class has been introduced in JDK 5 with Executor Framework. FutureTask class is the concrete implementation of the Future object and provides methods for start and cancel the task.It also provides method to see if the computation is done or not. We can query […]