Questions on Java

Friends , here is my first attempt , the SCJP book by Kathy has given me few questions ,  I would like to enrich it further , but time for a first cut

OOPS, Java

·         Is Java compiled or interpreted?

·         How can we declare two public classes in a Java source file?

·         Is there a restriction on naming the source file?

·         Give an example of code statement, where do while and while will give different output?

·         What is the default access, if we do not specify any access modifiers?

·         How method overloading and method overriding is different?

·         Give example of a non access modifier?

·         Why should some classes or methods be marked as final? 

·         How the abstract class is different from an interface as far as abstract methods are concerned?

·         How garbage collection works in C# and Java ?

·         What is boxing and Unboxing ?

·         How can we implement threads ?

·         What are the different states of a thread ?

·         What is a web service?  How this is related with SOAP, UDDI and WSDL?

·         What are the different ways to maintain state in a web application , relative advantage and disadvantages ? ( Hint : Session Variable, Cookies , Hidden Fields , Query String ) . For .Net view state is important.

·         What is MVC Architecture ?

·         Explain 3- tier Architecture ?

·         Explain Service oriented architecture

·         What is the difference between default and package access modifier

·         Let’s say Class A has a private method called fun() , class B extends Class A and defined fun() , what this phenomenon is called ?

·         What is the use of Final Keyword ?  Can we declare a variable as final ?

·         Is it possible to define a abstract class , with non abstract member s?

·         When should we use an arraylist in place of an array?

·         What is the method that can be used to traverse an arraylist?

·         What is checked and unchecked exception ?  Give example of both type of exceptions.

·         How to use your own exception , so let’s say you are taking age as an input and you want to throw an exception when it is less than zero, how will you achieve it ?

·         Give some example of statements that should be put in finally ?

·         Does Java allow multiple inheritance  ?  What is ‘Deadly Diamond of Death”

·         Class A

{

    public void fun()

 { 

}

}

Class B extend A

{

   Protected void fun()

}

Is there a problem in the above code ?

·         Give an example how polymorphism can be achieved using method overriding?

public int foo()

{

char c = ‘c’;

return c

}

Is this code legal ?

·         What is default constructor supplied by the compiler ? Is there any caution , that you need to follow when you create your own constructor,  will the default constructor be supplied in the following case

class Horse()

{

    void Horse ()

}

·         Which variables are in stack , which are stored in heap ?

·         What do we mean by saying strings are immutable objects ?   what is role of ‘String Constant Pool” . Which classed do we use to overcome the limitations of string ?