java questions

1. Object Oriented Programming(EE 604C) www.oopusingjava.webs.com
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Basic concepts of OOP
1. What is Object oriented Programming? Difference from structured programming?
2. Write 3 important advantages of Object Oriented Programming? Benefits of OOP
3. What do you mean by Objects and Classes? What is bottom up programming approach & top-down
approach?
4. Short Notes on: Data Abstraction, Encapsulation, Inheritance, Polymorphism, Dynamic Binding.
5. 5 most important features of Java(Object Oriented, Robust and secure Platform independent portable ,
Multithreaded ,Compiled and Interpreted)
6. Difference between java and c, java and C++
7. Contents of Java Development Kit, process of building and running java application programs
8. Short notes: JVM, Java Runtime Environment
9. What do you mean by Bytecode? Why java is called compiled and interpreted?
10. Why public static void main() is used ?
Class Objects and Methods
1. What do you mean by a Class? What are Objects?
2. What are fields and methods of a class? How to access each member of a class or objects?
3. How many keywords are there in JAVA
4. Why Java is machine neutral?
5. What are the basic data types in Java? Give the size in bytes of each.
6. What are Boolean variables? For what purpose they are used
7. What do you mean by type casting? Why it is required in programming? What is up-casting, widening or
narrowing casting?
8. Short notes: Scope of a variable, constant, variable.
9. What are the different Arithmetic operators in Java? Describe briefly the action of modulo division operator
10. What is enhanced for loop or for-each loop in java? Labeled loops
11. What is a ternary operator or short hand if-else operator? Explain Instanceof operator and dot operator
12. What do you mean by constructors? Describe with example.
13. What is method overloading? Describe with an example
14. What is method overriding? Give example. Difference between Method overloading and overriding
15. What are static members? What are the restrictions of using static methods
16. What is finalization? Why finalize() is used?
17. What are the different visibility controllers or modifiers in Java? Briefly describe each of them
18. When do declare a method or class final?
19. How do we invoke a constructor?
20. How does a class accomplish data hiding?

2. Object Oriented Programming(EE 604C) www.oopusingjava.webs.com
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Arrays and Strings
1. What are arrays? What are the two forms of declaring an array?
2. How we can obtain the length of an array
3. What are variable size arrays? Give examples
4. What are Strings in Java?
5. Compare between Strings and character arrays?
6. What are the two String Classes in java(String and StringBuffer)
7. Briefly Describe(with examples) the following String methods: toLowerCase(), toUpperCase(), replace(),
length(), equals(), indexOf(), compareTo(), cancat(), subString(),equalsIgnorecase(), toCharArray(), tostring()
8. What do you immutable and mutable Strings? What is use of toString() method?
9. What are the basic difference between String and StringBuffer Class?
Command line arguments and basics of I/O operations
1. What do you mean by Command Line Arguments? Describe with an example.
2. How Command line Arguments are received by a Java Program.
3. What type of objects are the command Line Arguments in Java
Inheritance and Multiple Inheritance(Interfaces)
1. What do you mean by inheritance? What are the different forms of inheritance in Java? Describe briefly each
one
2. What is super class and sub class? Explain single inheritance with an example
3. What is the use of super() in a sub class constructor. Explain with an example
4. What are the conditions for using keyword super in a sub class constructor?
5. How we can access the super class members (both fields and methods) from the sub-class by using keyword
super
6. What is an interface? How do we tell Java that the class we are creating implements a particular interface?
7. What are the major differences between an interface and a class?
8. How would you inherit an interface?
9. How to implement the concept of multiple inheritance using interfaces
Packages
1. What is a package? How do we tell Java that we want to use a particular package in a file
2. Discuss how to design a package. Usefulness of using package in Java program
3. How do we add a class or an interface to a package
4. How would you protect a class from accidental access?
5. How to import a package in a program. What is static import?
Exception handling
1. What is an Exception? How do define a try block? How do we define a catch block?
2. What are the most common types of errors that occur in Java? Is it necessary to catch all types of exceptions
3. Can we use multiple catch blocks with one try block. Explain with example.
4. Create a try block that is likely to generate three types of exception and then incorporate necessary catch
blocks to catch and handle them appropriately.
5. What is a finally block? When and how is it used? Explain briefly by an example
6. What do mean by checked and unchecked exceptions
Multithreading
1. What is a thread?
2. What is the difference between multiprocessing and multithreading?
3. What are the different ways of creating threads?
4. What Java interface must be implemented by all threads?
5. How do we start a thread?
6. What are the two methods by which we may stop threads?
7. Describe the complete life cycle of a thread.
8. What is the difference between suspending and stopping a thread?
9. How do we set priorities for threads?
10. What is synchronization? When do we use it?

3. Object Oriented Programming(EE 604C) www.oopusingjava.webs.com
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11. What is difference between using run() and start() a thread?
12. Which one is good way of creating threads: implementing or by extending
13. What is difference between yield() and sleep() methods
14. What do you mean by deadlock in multithreading? How to prevent deadlock?
Applet Programming
1. What is an applet? What is a local applet? What is an remote applet?
2. How an applet does works in a client/server relationship?
3. How do applets differ from application programs?
4. How many arguments can be passed to an applet using <PARAM> tag
5. Describe the life cycle of an applet
6. Why do applet classes need to be declared as public?
7. Distinguish between init() and start() methods.
8. What is swing? How you can make an applet by using swing?