What is the difference between Mock and Stub? A Mock is generally a dummy object where certain features are set into it initially. Its behavior mainly depends on these features, which are then tested. A Stub is an object that helps in running the test. It functions in a fixed manner under…

Name three commonly used tools for Microservices Wiremock, Docker, and Hystrix are important Microservices tools. Why do we need Containers for Microservices? To manage a microservice-based application, containers are the easiest alternative. It helps the user to individually deploy and develop. You can also use Docker to encapsulate the microservice in…

What is monolithic architecture? Monolith means something which is composed all in one piece. The Monolithic application describes a single-tiered software application in which different components are combined into a single program from a single platform. The monolithic software is designed to be self-contained. …

In this post, we will learn about common coding mistakes in Java, which lead to a vulnerable application. Also, we are going to learn to avoid SQLi. What is SQL injection? SQLi or SQL injection is an attack where a hacker manages to inject unauthorized SQL query language code into an…

What is ThreadLocal variable in Java? ThreadLocal is a special class for which each thread accessing the variable would have a separate instance of it. This was introduced on JDK 1.2 but it was later generified in JDK 1.4 to introduce type safety on ThreadLocal variable. The ThreadLocal variable becomes…

What happens when an exception occurs in a thread? If an exception is not caught thread will die, else if an uncaught exception handler is registered then it will get a callback. What is the use of Thread.UncaughtExceptionHandler interface? Thread.UncaughtExceptionHandler is an interface, defined as a nested interface for handlers invoked…

What is a race condition in Java? Race conditions occur when two threads operate on the same object without proper synchronization and their operation interleaves on each other. It is a situation in which two or more threads or processes are reading or writing some shared data, and the final…

What are the different states of a thread’s lifecycle? Runnable: waiting for its turn to be picked for execution by the thread scheduler based on thread priorities. Running: The processor is actively executing the thread code. It runs until it becomes blocked, or voluntarily gives up its turn with this…

What is a volatile variable in Java? volatile variable in Java is a special variable that is used to signal threads, a compiler that the value of this particular variable is going to be updated by multiple threads inside the Java application. When we make a variable volatile, we ensure…