Indian Learners Own Academy

INDIAN LEARNERS OWN ACADEMY INFORMATICS PRACTICES - XII ASSIGNMENT 3 GUI PROGRAMMING - A REVIEW Submission Date: 10-04-2017

1. Identify the following as valid variable names, state reason if invalid. a) _123 b)break c)var.1 d)S$ f)D123 g) A * 4 h) D 23 i) roll_no e) emp No g) withdrawamt

2. What will be the result of a = 5/3 if a is (i) float (ii) int? 3. What will be the value of j = --k + 2*k + l ++ if k is 20 initially? 4. What will be the value of P=P* ++ J where J is 22 and P = 3 initially? 5. What will be the resultant type of the following expression if bh represents a byte variable, i is an int variable, fl is a float variable and db is a double variable? (i) bh – I + db/fl – i*fl + db/i (ii) (int) (fl + db) 6. If a String MyString holds a value “12345”, then write the command to convert it into integer type. 7. What will be the output of the following statement? jTextField1.setText(“1”+3); 8. What will be the output of the following statement? int x; x=5; jTextArea1.append(String.valueOf(x++)); jTextArea1.append(String.valueOf(x)); jTextArea1.append(String.valueOf(++x)); 9. What will be the output of the following statement? int a; a= 25 + 4 – 4; jTextField1.setText(“a = “ + String.valueOf(a)); 10. What will be the output of the following statement? int a, b = 30; a = 30 / 2 * b; jTextField1.setText(String.valueOf(a)); 11. What will be the output of the following statement? int p = 10, k = 20; k = k / ++p; jTextField1.setText(“k = “ +String.valueOf(a)); 12. Determine the output int z, x = 5, y= -10, a = 4, b = 2; z = x++ - --y * b/a;

13. Write the results of the following Java statements: int a= 10, b = 4, c, d; c = ++a – b-- * 2; d = a/2 * 5 - --b; jTextField1.setText(String.valueOf(c)); jTextField1.setText(String.valueOf(d));

14. Write a program to calculate area of a circle using Input.

15. What kind of constant are the following : 14, 011, 0X2A, 17, 014, 0XBC1

16. Write the output of x in the following case: int x = (5>=8) ? 1 : 2;

17. Write code in java that takes two Strings from textfields t1 and textfields t2 and display them joined together in a third textfield t3.

18. What will be the content of jTextField1 after executing the following code: int Num = 6; Num = Num + 1; if ( Num > 5) jTextField1.setText(Integer.toString(Num)); else jTextField1.setText(Integer.toString(Num+5));

19. Predict the value of C and D if they are of Boolean types if a and b are integers with values a=38 and b= - 10 then C=(a>30)&&(b>-20); D=!((a<22)||(a>10));

20. Write the value of variable ‘c’ after execution of the following code : int d = 7,c; c = (5*++d)%3; 21. Write Java code to assign the value 500 to variable x. Increase the value of x by 50 and store it in variable y. 22. Write the values of sum and x after execution of the following code : int sum, x; sum = 7; x = 5; sum = sum + (x++);

23. What will be the value X1 after the execution of the following code : String X1="Spread", X2="PEACE"; X1=X2.concat(X1);

24. What will be the content of the jTextArea1 after executing the following code : int n = 89; jTextAreal.setText(Integer.toString(++n);

25. Which of the following are valid identifiers? (i) int $y; (ii) int 678 (iii) int _333

26. What is the output of the following, if the initial value of X is 40? (i) Y = ++ X; (ii) Y = X++;

27. Write java code that takes the cost of a pencil from jTextField1 and number of pencil from jTextField2 and calculate total amount as cost*number to be displayed in jTextField3 and 20% service tax out of total amount in jTextField4.

28. Write java code that takes value for a number (n) in jTextField1 and cube (n*n*n) of it to be displayed in jTextField2.

29. Item code consisting of 5 digits is stored in an integer type variable intItemCode. Mr. Srikant wants to store this Item code in a String type variable called strItemCode. Write appropriate java statement(s) to help her in performing the same.

30. What will be the value ofa and b after execution of the following code : int a=1,b=2; if (++a<5) { a* = ++b; }