Java is a class-based object-oriented general-purpose computer programming language that was designed to have as less dependent implementations as possible. Users writing their programs in Java only have to write the code once. They can run it anywhere and won’t need to re-compile the code again and again.
If you have ever heard of C++, then you exactly know what I am talking about. It is very similar to the C language, except it has fewer low-level computer language facilities.
This was a short introduction to Java. Now, let’s see the most common Java programming questions in the world:
Why Is Java Only Called the Platform Independent Computer Language?
This is the most common Java programming question. There’s a definition of a platform-independent language. It means that the compilation and execution of your program won’t depend on any particular operating system. the good thing about Java is that it is both, a compiler and an interpreter.
The program written in Java can easily be converted into machine language using the JVM compiler. The JVM compiler is not dependent on any operating system. hence, it is called a platform-independent language.
What Is the “Final” Keyword in Java?
The final keyword is that particular word that restricts the use of any class, method or variable. As the value of the final variable is constant, you cannot change it. You cannot inherit from a final class and similarly, the final method cannot be overridden.
When Do You Use the “Super” Keyword?
- It is used to refer to an immediate parent class method.
- It is used to refer to an immediate parent class variable.
- It is used to refer to an immediate parent class constructor.
What Is the Slight Difference Between A String and String Buffer?
These 2 are types of classes. You cannot mutate the string class. Once the content is defined, you cannot change it. Whereas, the class string buffer is mutable. You can change the content of the class. This is the reason why performance is way better while using the string buffer class.
Why Cannot You Use Multiple Inheritance in Java?
Java supports multiple inheritances through its interference and not through the classes. Java is a simple object-oriented programming language and multiple inheritances through classes can make complex issues.
In multiple inheritances, the multiple inheritances with two or more classes having methods has some conflicts. That is why the creators did not allow multiple inheritances in Java.
Can A Class Be Protected in Java?
The top-level class in this programming language cannot be protected. However, the inner classes in Java can be protected. The reason to not protect the top class is pretty obvious. Nobody can ever use a private class so protecting or even declaring the top-level class does not make any sense.
What Is the Main Difference Between ‘Throw And ‘Throws’ in Java Exception Handling?
‘Throws’ determines the type of exception which can be thrown by the particular method. Whereas, the ‘throw’ can determine the exception for any method.
By research gained from different interview questions, I have found that these 6 questions were frequently asked. If you are learning Java or appearing for a Java-based interview, it’s better to be prepared to keep these Java programming questions in mind.