Core Java - Interview Questions and Answers for 'Different types of classes' - 1 question(s) found - Order By Newest Q1. What are different types of classes ? Core Java
Ans. There are different verticals in which Java Classes can be classified.
1. Access - Public , Private , default or Protected.
2. Packaging - System, library or User Defined
3. Structure - Outer or Inner
4. Object Derivation - Abstract Class or Concrete Class.
5. Object Creation - Normal, Singleton , Doubleton , Immutable or Enum.
6. Functionality - String , Util , Stream etc. Help us improve. Please let us know the company, where you were asked this question : Like Discuss Correct / Improve  classes   different types of classes Asked in 1 Companies Try 1 Question(s) TestRelated Questions Why do we need Inner classes ? Cant we just work with outer classes wherever we implement Inner classes ? Differences between abstract class and interface ? Will this code give error if i try to add two heterogeneous elements in the arraylist. ? and Why ? Which of the following can be marked static ?
a. Methods , Variables and Initialization Blocks.
b. Methods , Variables , Initialization Blocks and Outer Classes and nested Classes.
c. Methods , Variables , Initialization Blocks and Outer Classes.
d. Methods , Variables , Initialization Blocks and nested Classes What is the difference between the following two code lines ?
1. new OuterClass().new InnerClass();
2. new OuterClass.InnerClass(); What are the Wrapper classes available for primitive types ? What are wrapper classes ? Why Struts 1 Classes are not Thread Safe whereas Struts 2 classes are thread safe ? What is a stream and what are the types of Streams and classes of the Streams?