Core Java interview

Runnable and Callable interface both are used in the multithreading environment.Callable is available in java.util.concurrent.Callable package and Runnable in java.lang.Thread. Difference between Runnable and Callable interface in java Runnable was introduced in java 1.0 version While Callable is an extended version of Runnable and introduced in java 1.5 to address the limitation of Runnable. Runnable […]

In this post, we will see the difference between map and flatMap in java.I have already covered Stream’s map and flatMap methods  in previous articles. As you might know, Stream’s map and flatMap method both can be applied on Stream<T> and return Stream<R> as output. The actual difference is, map operation produces one output value […]

In this post, we will see about Parallel Stream in java. Java Parallel Stream introduction Java 8 introduces the concept of parallel stream to do parallel processing. As we have more number of cpu cores nowadays due to cheap hardware costs, parallel processing can be used to perform operation faster. Let’s understand with help of […]

In this post, we will see top Java technical interview asked in the Core Java interview.I have covered a lot of interview question on Java programming. Here is list of other java interview question you might find useful. Core java interview questions Java Collections interview questions Java String interview questions OOPs interview questions in java […]

In this post, we will some important interview questions specifically on Java 8. Java has changed a lot over years and Java 8 has introduced many new features which you need to know when you are preparing for Java interview.  Here is a list of most asked Java 8 interview questions. 1)  What are […]

In this post, I am going to share java interview questions which are generally asked on immutable class. Immutable class is important topic as it deals with creation of thread safe class. Here I am providing some important immutable class interview questions with answers. 1. What is immutable class? Answer : Immutable objects are those […]

In this tutorial, we are going to see Method overloading and overriding interview questions. 1. What is method overloading? Answer: If two or more methods have same name, but different argument then it is called method overloading. For example: Array’s sort method have many overloaded versions. You can sort array of double, int, String etc. 2. […]

Serialization is one of most important concept in java. If you are going to face core java interview, then you might be asked some questions from Serialization. Java Serialization Tutorial: Serialization in java Java Serialization interview questions and answers serialversionuid in java serialization externalizable in java Transient keyword in java Difference between Serializable and Externalizable […]

Exceptional handling is one of the most important topics in core java. Here is list of questions that may be asked on Exceptional handling. Question 1: What is Exception ? Answer: Java doc says “ An exception is an event, which occurs during the execution of a program, that disrupts the normal flow of the program’s […]