java interview questions for experienced and answers,java interview questions for 4 years experience and answers,java interview questions for 5 years experience and answers,java interview questions for 3 years experience and answer,java experienced interview questions and answers,java experience interview questions and answers,java experience interview questions and answers pdf,java interview questions and answers for experienced j2ee,java interview questions and answers for experienced pdf,java interview questions and answers for experienced pdf core,java interview questions and answers for experienced free download
java interview questions for experienced and answers:
Java Language Interview Question and Answers
1. | What is an abstract class? |
| Abstract class is a class which contain one or more abstract methods, which has to be implemented by sub classes. An abstract class can contain no abstract methods also i.e. abstract class may contain concrete methods. |
2. | what are class variables? |
| Class variables are global to a class and belong to the entire set of objects that class creates. Only one memory location is created for each variable. |
3. | What is the Collection interface? |
| The Collection interface provides support for the implementation of a mathematical bag - an unordered collection of objects that may contain duplicates. |
4. | What must a class do to implement an interface? |
| The class must provide all of the methods in the interface and identify the interface in its implements clause. |
5. | What is the Collections API? |
| The Collections API is a set of classes and interfaces that support operations on collections of objects. |