cmpu102 midterm practice/sample questions
see wiki schedule for complete set of topics being covered (through week 6).
*OOP concepts
*JVM basics
*data fields/variables
*data types: POD and class types
*operators (including short hand operators)
* if/else
*switch/case
*loops: for, while, do...while
*special statements return, break, continue.
*keywords
*new keyword
*static keyword
*final keyword
*this keyword
*constructors


//(20 pts.) The following questions refer to exception handling. 
//Assume there are no syntax errors in any of the
//code fragments (A through D).
//(A) (5 pts.) What is the output of the following code fragment?

try {
   int num1 = Integer.parseInt("14");
   System.out.println("Okay 1");
   int num2 = Integer.parseInt("one");
   System.out.println("Okay 2");
} catch (NumberFormatException nfe) {
   System.out.println("Error");
}

(B) (5 pts.) What is the output of the following code fragment?
try {
  int number = Integer.parseInt("-30"); 
  if (number < 0) {
     throw new Exception("No negative numbers please.");
  }
} catch (Exception e) {
   System.out.println("Error: "+ e.getMessage());
} catch (NumberFormatException nfe) {
   System.out.println("Cannot convert to int.");
}

(C) (5 pts.) Consider the following code fragment:
try {
   int number = Integer.parseInt(JOptionPane.showInputDialog(null, "Input:"));
   if ( number != 0 ) {
      throw new Exception("Number not zero.");
   }
} catch (NumberFormatException nfe) {
   System.out.println("Cannot convert to int");
} catch (Exception e) {
   System.out.println("Error: " + e.getMessage());
}

(D) (5 pts.) Determine the output when the input is:
a)   -1  ______________________

b)    0  ______________________

c) 12XY  ______________________



//
//(20 points, 1 point each) Answer the following questions by circling T (true) or F (false) 

a) T or F: Java provides 8 numerical primitive types. 
short, int, long, float, double, boolean, char, byte... see chart in links section.

b) T or F: When passing arguments to a method, the type of the argument must be assignment compatible
with the type of the parameter declared in the method.

c) T or F: When the keyword "void" is used in a method declaration, it means that there will be no value
returned by the method.

d) T or F: Each Java class type has a set of literal constant values that can be stored as the value of a
variable for that type. 

e) T or F: Naming a variable A3xYz would cause a syntax error.

f) T or F: Java belongs to the category of computer languages known as "machine" languages.

g) T or F: The number of vertical spaces (blank lines) between statements in a Java program is irrelevant.

h) T or F: The Java Virtual Machine (JVM) allows for Java programs to be built once and run on any operating
system (OS).

i) T or F: A return statement can be present in any method.

j) T or F: Java programs do not need to import the java.lang package in order to use the shorthand notation
for classes defined in that package.

k) T or F: Naming an int variable 8Ball would cause a syntax error.

l) T or F: Once all syntax errors are corrected, a Java program will execute as intended. 
l) T or F: Once all syntax errors are corrected, a Java program will execute as coded. 

m) T or F: Given the following statements: char letter = '3'; int number = 8; the subsequent state-
ment int result = letter + number; will return a syntax error. 

n) T or F: The value returned, if the value of the int variable count is 0 and the value of the int variable
limit is 10, as the result of evaluating the expression (count == 0) && (limit < 20) is true.

o) T or F: An if decision statement must be followed by at least one else statement with which it is paired



//(10 points) Write a method called multEven that takes an int n as input and returns an int that is the product
//of all even whole numbers between 2 and n. Use a while loop in your solution.


// (5 points) Circle 5 syntax errors in the following program and explain why each is an error:
//
1. /*
2.    Program Problems
3. */
4. class Problem 1{
5. public static myMethod(String st)
6. {
7.    i = 5;
8.    double backUp = 1.0/5;
9.    return backUp
10. }
11. }


//(5 points) Give the output of the following code if the call to this method is:
==> PetStore.buyCompanion(0);
(assume there are no syntax errors)
public class PetStore {
   public static void buyCompanion(int k) {
      switch (k + 3) {
         case 1:
            System.out.println("Puppy");
         case 2:
            System.out.println("Macaw");
            break;
         case 3:
            System.out.println("Kitten");
         case 4:
            System.out.println("Goldfish");
            break;
         default:
            System.out.println("Cricket");
            break;
      }
   }
}

(15 points) Rewrite the class in the last problem using an if, else if, else multibranch statement instead of a
switch to get the same results as the switch statement.--_mixed 007462DE8525851A_--