NielsenIQ Support Specialist Interview Questions and Answers

Multithreading in Java refers to the concurrent execution of two or more parts of a program for maximum utilization of CPU.

• Multithreading allows multiple threads to run concurrently within a single program.

• It improves the performance of the program by utilizing the CPU more efficiently.

• Java provides built-in support for multithreading through the java.lang.Thread class.

• Multithreading can be used for tasks such as backg...read more

CPU scheduling policies include FCFS, SJF, Round Robin, Priority, and Multilevel Queue. The operating system does the scheduling.

• FCFS (First Come First Serve)

• SJF (Shortest Job First)

• Round Robin

• Priority

• Multilevel Queue

• Operating system does scheduling

Jvm is Java Virtual Machine. It manages threads on its own.

• Jvm is a virtual machine that executes Java bytecode.

• It provides a runtime environment for Java programs.

• Jvm manages threads on its own using its own thread scheduler.

• Jvm is platform-independent and provides a layer of abstraction between the Java code and the underlying operating system.

• Examples of popular JVM implementations include Oracle's HotSpot and OpenJ

Tree traversal is a technique to visit all nodes of a tree in a specific order.

• There are three types of tree traversals: inorder, preorder, and postorder.

• Inorder traversal visits the left subtree, then the root, and then the right subtree.

• Preorder traversal visits the root, then the left subtree, and then the right subtree.

• Postorder traversal visits the left subtree, then the right subtree, and then the root.

• For exampl...read more

ArrayList and Vector are both dynamic arrays, but Vector is synchronized and slower. Traversing a Vector is similar to an ArrayList.

• ArrayList is not synchronized, while Vector is synchronized.

• ArrayList is faster than Vector, but Vector is thread-safe.

• To traverse a Vector, we can use a for loop or an iterator, similar to an ArrayList.

• Example: Vector v = new Vector<>(); for(String s : v) { //do something }