Chapter 3 Programming Fundamentals

Chapter 3 

PROGRAMMING FUNDAMENTALS 

Questions and Answers

Q1.     Name any two Object Oriented Programming languages? Ans.    C++ and Java

Q2.     Why is java called a platform independent language?

Ans     Java program can be easily moved from one computer system to another, anywhere anytime.
            Changes and upgrade in operating system, processors and   system resources will not force any
            change in the Java program. Hence it is called a platform independent language.
 Q3.     Elaborate the java Compilation process.

Ans.    The source program is first converted into a byte code using a java compiler. This byte code is
            machine independent i.e. same for all the machines. Later the byte code is executed on the
            machine using an interpreter.

Q4.      Why do we write a comment in a program? What are the two ways of wr

java Program?

Ans.    Comments are added to a program for the following purposes:-

1.          Make the more readable and understandable

2.         For future references we can add comments in a Java program in the following ways:

i)       Adding // before the line which is to be commented. This can be used only for single

line comments.

ii)      using a pair of /* and */ for multi-line comments.

Q5.      What is a syntax error in context of a program? Give an example.

Ans.    Error in the way of writing a statement in a program, results in a syntax error.

For e.g.

for ( i=0, i<=100. i++), will result in a syntax because the program has written

comma instead of a semi comma in the for loop.

Q6.      What is RAD programming? Why is program development in java using Netbeans IDE is

RAD?

Ans.    RAD stands for Rapid Application Development. A programming style which aims at building

programs fastly through the use of tools and wizards is called RAD.

Program development using Netbeans IDE is RAD as it

• provides GUI

• Provides online help and suggestions during typing of the program (using ctrl+ Spacebar key)

• Error alerts while typing of the program.

Q7.      What is IDE? Name two IDE for Programming in java.

Ans.    A programming environment, where all the tools required for programming are available under

one roof is called IDE. Two IDE for Java are Netbeans and BlueJ

Q8.      Name any two type of Tokens available in Java.

Ans.    Keyword, Identifier, Literal, Punctuators ad Operators.

Q9.      What are primitive data types? Name the various primitive data type available in Java.

Ans.    Data types that are directly available with java are called primitive data type.

Various primitive data types available in java are byte, short, int, long, float,

double, char and boolean.

Q10.    What are Reference data types?

Ans.    Data types created by the programmer using the primitive data type are called

reference data type e.g. Classes, interfaces etc.

Q11.    What is type casting?

Ans.    Converting a value form one type to another is called type casting.

For e.g. int a = 5 . here ‘a’ is a integer, which can be cased to float as follows float b = (float) a;

Q12.    Name and explain the usage of any two data types used in Java to store numbers with decimals.
Ans. Two data types available in java for storing numbers with decimals are

1. float: for single precision floating point values for e.g. float num = 10.0F

2. double: for double precision floating point value. This is the default data type

for decimal numbers. for e.g. double num = 10.0

Q13.    What are Keywords? Give two examples of keywords available in Java.

Ans.    Keywords are words that have a specific predefined meaning in Java. They cannot be used as

variable names. Eg. void, private, if, while etc.

Q14.    Name and explain the usage of any one relational and one logical operator in Java.

Ans.    One relational operator in java is ==. This operator results in true if both its operands are equal

otherwise false. One logical operator in java is &&. This operator is used to combine two logical values. The result of the && will be true if and only if both its operands are true otherwise false.

Q15.    What is the difference between = and == operator in java?

Ans.    Represent an assignment operator. It sets the value of the variable on its left   side with the

result of expression on its right side. == represent a conditional equal to operator. It checks for

the equality of both its operands. If both the operands are equal, cond otherwise to false.

Q16.    Name the two type of selection statement available in Java.

Ans.    Two selection statement available in java are ‘if’ and ‘Switch’

Q17.    Write the purpose of Switch Statement with the help of an example. Which Java Statement can

be used in place of switch statement? In the switch statement, what happens if every case fails and there is no default option?

Ans.    A Switch statement is used execute a statement from a group of statement based on the result

of a expression. The expression must result in either of byte, short, integer or character.

An ‘if statement’ can be used in place of switch statement. In a switch statement if none of the statement satisfies and even there is no default case then nothing would happen. This would not result in any sort of error.

Q18.    What is the purpose of ‘break’ statement in java?

Ans.    Break is used to terminate the current switch statement or the loop.

Q19.    What is the purpose of ‘continue’ statement in java?

Ans.    Continue statement skips the remaining part of the current loop and begins the next iteration of

the loop.

Q20     Find the output of the following code snippet written in java public static void main(String [

]args)

{

long a=78345,s1=0,s2=0,r;
while(a>0)

{

r=a%10;

if (r%4==0)
s1+= r;

else

s2+=r;

a/=10;

}

System.out.println("S1 ="+ s1);
System.out.println("S2 ="+ s2);
}

Ans.    Output:

s1= 12
s2= 15

Q21. Correct the errors in the following program segment written in JAVA. You are just required to
        write the corrected code, underlying the corrections made.

public Static Void Main (String [] args)

{

Integer Nos = 100;
while (Nos => 45)
{

If (Nos % 5 = 0);
Nos+=10;

otherwise
Nos + = 20;
}

}

Ans:    Corrected Code

public static void main (String [] args)
{

int Nos = 100;

while (Nos >= 45)

{

if (Nos % 5 == 0)_
Nos+=10;

else

Nos + = 20;
}

}