C Programs Tutorials | IT Developer
IT Developer

Java Programs

Share with a Friend
Previous
HOME
Next

Short Questions/Answers - Java Programs

Question 1
Choose the correct answer to the questions from the given options.

(i)

Name the above structure:

(a) One dimensional array
(b) Two-dimensional array with 4 rows and 5 columns
(c) Three-dimensional array
(d) Two-dimensional array with 5 rows and 4 columns

(ii) “Java compiled code (bytecode) can run on all operating systems.”
– Name the feature.

(a) Robust and Secure
(b) Object-Oriented
(c) Platform-independent
(d) Multithreaded

(iii) The size of ‘\n’ is:

(a) 2 bytes
(b) 4 bytes
(c) 8 bytes
(d) 16 bytes

(iv) Identify the operator that gets the highest precedence while evaluating the given expression: a + b % c * d – e


(a) +
(b) %
(c) –
(d) *

(v) Which of the following is a valid Java keyword?

(a) If
(b) BOOLEAN
(c) static
(d) Switch

(vi) The output of the following code is:
System.out.println(Math.ceil(6.4) + Math.floor(-1-2));

(a) 3.0
(b) 4
(c) 3
(d) 4.0

(vii) Which of the following returns a String?

(a) length()
(b) charAt(int)
(c) replace(char, char)
(d) indexOf(String)

(viii) Which of the following is not true with regards to a switch statement?

(a) checks for an equality between the input and the case labels
(b) supports floating point constants
(c) break is used to exit from the switch block
(d) case labels are unique

(ix) Consider the array given below:
char ch[] = {‘A’, ‘E’, ‘I’, ‘O’, ‘U’};
Write the output of the following statement:
System.out.println(ch[0] * 2);

(a) 65
(b) 130
(c) ‘A’
(d) 0

(x) To execute a loop 10 times, which of the following is correct?

(a) for(int i = 11; i <= 30; i += 2)
(b) for(int i = 11; i <= 30; i += 3)
(c) for(int i = 11; i < 20; i++)
(d) for(int i = 11; i <= 21; i++)

(xi) A single dimensional array has 50 elements, which of the following is the correct statement to initialize the last element to 100?

(a) x[51] = 100;
(b) x[48] = 100;
(c) x[49] = 100;
(d) x[50] = 100;

(xii) Method prototype for the method compute which accepts two integer arguments and returns true/false.

(a) void compute(int a, int b)
(b) boolean compute(int a, int b)
(c) Boolean compute(int a, b)
(d) int compute(int a, int b)

(xiii) The statement that brings the control back to the calling method is:

(a) break
(b) System.exit(0)
(c) continue
(d) return

(xiv) The default value of a boolean variable is:

(a) False
(b) 0
(c) false
(d) True

(xv) The method to convert a lowercase character to uppercase is:

(a) String.toUpperCase()
(b) Character.isUppercase(char)
(c) Character.toUpperCase(char)
(d) toUpperCase()

(xvi) Assertion (A): Integer class can be used in the program without calling a package.
Reason (R): It belongs to the default package java.lang.

(a) Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A)
(b) Both Assertion (A) and Reason (R) are true and Reason (R) is not a correct explanation of Assertion (A)
(c) Assertion (A) is true and Reason (R) is false
(d) Assertion (A) is false and Reason (R) is true

 

(xvii) A student executes the following code to increase the value of a variable ‘x’ by 2.
He has written the following statement, which is incorrect.
x =+ 2;
What will be the correct statement?
A. x += 2;
B. x = 2;
C. x = x + 2;

(a) Only A
(b) Only C
(c) All the three
(d) Both A and C

(xviii) The statement used to find the total number of strings present in the String array String s[] is:

(a) s.length
(b) s.length()
(c) length(s)
(d) len(s)

(xix) Consider the following program segment in which the statements are jumbled. Choose the correct order of statements to swap two variables using the third variable.

void swap(int a, int b){

    a = b; --> (1)

    b = t; --> (2)

    int t = 0; --> (3)

    t = a; --> (4)

}

(a) (1) (2) (3) (4)
(b) (3) (4) (1) (2)
(c) (1) (3) (4) (2)
(d) (2) (1) (4) (3)

(xx) Assertion (A): An argument is a value that is passed to a method when it is called.
Reason (R): Variables which are declared in a method prototype to receive values are called actual parameters.

(a) Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A)
(b) Both Assertion (A) and Reason (R) are true and Reason (R) is not a correct explanation of Assertion (A)
(c) Assertion (A) is true and Reason (R) is false
(d) Assertion (A) is false and Reason (R) is true

Question 2

(i) Rewrite the following code using single if statement.

if(code == 'g')

    System.out.println("GREEN");

else if(code == 'G')

    System.out.println("GREEN")

 

OUTPUT:

 

if(code == 'g' || code == 'G')

    System.out.println("GREEN");

 

(ii) Evaluate the given expression when the value of a = 2 and b = 3.

b *= a++ – ++b + ++a;
System.out.println(“a = ” + a);
System.out.println(“b = ” + b);

OUTPUT:

 

b = b * (a++ – ++b + ++a)
b = 3 * (2 – 4 + 4)
b = 3 * 2
b = 6

 

(iii) A student executes the following program segment and gets an error. Identify the statement which has an error. Correct the same to get the output as WIN.

boolean x = true;
switch(x){
case 1: System.out.println("WIN"); break;
case 2: System.out.println("LOOSE");
}

 

OUTPUT:


boolean x = true;
switch(x){
case true: System.out.println("WIN"); break;
case false: System.out.println("LOOSE");
}

 

(iv) Write the Java expression for:

OUTPUT:

 

Math.cbrt(x) + Math.sqrt(y)

(v) How many times will the following loop execute? Write the output of the code:

int x = 10;
while(true){
   System.out.println(x++ * 2);
   if(x % 3 == 0)
      break;
}

 

OUTPUT:
20
22
The loop executes 2 times.

(vi) Write the output of the following String methods:
String x = “Galaxy”, y = “Games”;

(a) System.out.println(x.charAt(0) == y.charAt(0));
(b) System.out.println(x.compareTo(y));

OUTPUT:

 

(a) true
(b) -1

(vii) Predict the output of the following code snippet:

char ch = 'B';
char chr = Character.toLowerCase(ch);
int n = (int)chr - 10;
System.out.println((char)n + "\t" + chr);

 

OUTPUT:

 OUTPUT:X       b

(viii) A student is trying to convert the string present in x to a numerical value, so that he can find the square root of the converted value. However, the code has an error. Name the error (syntax/logical/runtime). Correct the code so that it compiles and runs correctly.

String x = "25";
int y = Double.parseDouble(x);
double r = Math.sqrt(y);
System.out.println(r);

 

OUTPUT:


It is a syntax error.
String x = "25";
int y = Integer.parseInt(x);
double r = Math.sqrt(y);
System.out.println(r);

(ix) Consider the following program segment and answer the questions below:

class calculate{
      int a; double b;
      calculate(){
          a = 0;
          b = 0.0;
      }


  calculate(int x, double y){
       a = x;
       b = y;
   }


  void sum(){
      System.out.println(a * b);
   }
}

Name the type of constructors used in the above program segment.

OUTPUT:

 

Non-parameterized and parameterized constructors.

(x) Consider the following program segment and answer the questions given below:
int x[][] = {{2, 4, 5, 6}, {5, 7, 8, 1}, {34, 1, 10, 9}};

(a) What is the position of 34?
(b) What is the result of x[2][3] + x[1][2]?

OUTPUT:

(a) x[2][0]
(b) 9 + 8 = 17

Previous
Next