Midterm Solution

QUESTION 1

1. A search for an item X in an array starts at the lower end of the array, and then looks for X by comparing array items to X in order of increasing subscript. Such a method is called



selection search


lower to upper search


sequential search


binary search


QUESTION 2

1. Constraining a type parameter in a generic class



can only be used when the generic class will be used as a superclass for other classes


causes programs to compile faster


restricts the types that can be used as type arguments


was added to Java in version 1.3 of the language


QUESTION 3

1. In a string that contains a series of words or other items of data separated by spaces or other characters, the programming term for the spaces or other characters is



Delimiter


Separator


Token


Buffer


QUESTION 4

1. In the following statement, which is the interface?

public class ClassA extends ClassB implements ClassC



ClassA


ClassB


ClassC


Cannot tell


QUESTION 5

1. Look at the following statement.

import java.util.*;

This is an example of



a wildcard import


conditional import


unconditional import


an explicit import


QUESTION 6

1. The scope of a private instance field is



Inside the class, but not inside any method


The instance methods of the same class


The method in which they are defined


Inside the parentheses of a method header


QUESTION 7

1. Under Windows, which of the following statements will open the file InputFile.txt that is in the root directory on the C: drive?



FileReader freader = new FileReader("C:\InputFile.txt");


FileReader freader = new FileReader("/c/InputFile.txt");


FileReader freader = new FileReader("C:\InputFile\txt");


FileReader freader = new FileReader("C:\\InputFile.txt");


QUESTION 8

1. What will be the value of x[1] after the following code is executed?

int[] x = { 22, 33, 44 };
arrayProcess(x);
...
public static void arrayProcess(int[] a)
{
for(int k = 0; k < 3; k++)
{
a[k] = a[k] + 5;
}
}





49


33


27


38


QUESTION 9

1. What would be the results of the following code?

final int SIZE = 25;
int[] array1 = new int[SIZE];
... // Code that will put values in array1
int value = 0;
for (int a = 0; a <= array1.length; a++)
{
value += array1[a];
}



value contains the sum of all the values in array1


value contains the lowest value in array1


value contains the highest value in array1


This would cause the program to crash


QUESTION 10

1. When an array is passed to a method



The method has direct access to the original array


A reference to the array is passed


It is passed just as an object


All of the above


QUESTION 11

1. Which of the following for loops is valid, given the following declaration?

String[] names = {"abc", "def", "ghi", "jkl"};



for (int i = 0; i < names.length; i++)
System.out.println(names[i].length());




for (int i = 0; i < names.length(); i++)
System.out.println(names[i].length);




for (int i = 0; i < names.length; i++)
System.out.println(names[i].length);




for (int i = 0; i < names.length(); i++)
System.out.println(names[i].length());




QUESTION 12

1. Which of the following is the correct boolean expression to test for: int x being a value between, but not including, 500 and 650, or int y not equal to 1000?



((x = 500 && x <= 650) && (y != 1000))


((x 500 && x < 650) || (y != 1000))


((x < 500 && x 650) || !(y == 1000))


((x 500 AND x < 650) OR !(y.equal(1000)))


QUESTION 13

1. A protected member of a class may be directly accessed by



Methods of the same class


Methods of a subclass


Methods in the same package


All of these


QUESTION 14

1. A subclass class can directly access



All members of the superclass class


Only public and private members of the superclass class


Only protected and private members of the superclass class


Only public and protected members of the superclass class


QUESTION 15

1. Every class has a toString method and an equal's method inherited from the Object class.

True

False



QUESTION 16

1. If a subclass constructor does not explicitly call a superclass constructor,



It must include the code necessary to initialize the superclass fields


The superclass fields will be set to the default values for their data types


Java will automatically call the superclass's default constructor immediately after the code in the subclass's constructor executes


Java will automatically call the superclass's default constructor just before the code in the subclass's constructor executes


QUESTION 17

1. If a superclass does not have a default constructor,



Then a class that inherits from it, must initialize the superclass values


Then a class that inherits from it, must call one of the constructors that the superclass does have


Then a class that inherits from it, does not inherit the data member fields from the superclass


Then a class that inherits from it, must contain the default constructor for the superclass


QUESTION 18

1. If two methods in the same class have the same name but different signatures, the second overrides the first.

True

False



QUESTION 19

1. An exception's default error message can be retrieved using this method.



getMessage()


getErrorMessage()


getDefaultMessage()


getDefaultErrorMessage()


QUESTION 20

1. If a method does not handle a possible checked exception, what must the method have?



A catch clause in its header


A try/catch clause in its header


A try clause in its header


A throws clause in its header


QUESTION 21

1. In a catch statement, what does the following code do?

System.out.println(e.getMessage());



It prints the stack trace


It prints the error message for an exception


It prints the code that caused the exception


It overrides the toString method


QUESTION 22

1. In a try/catch construct, after the catch statement is executed



The program returns to the statement following the statement in which the exception occurred


The program terminates


The program resumes at the statement that immediately follows the try/catch construct


The program resumes at the first statement of the try statement


QUESTION 23

1. In the following code, assume that inputFile references a Scanner object that has been successfully used to open a file:


What will be the value of totalIncome after the following values are read from the file?
2.5
8.5
3.0
5.5
abc
1.0



19.5


0.0


35.5


75.0


QUESTION 24

1. Look at the following code:




DataInputStream inputFile =
new DataInputStream(new FileInputStream("MyInfo.dat"));



QUESTION 25

1. The catch clause



follows the try clause


starts with the word catch followed by a parameter list in parentheses containing an ExceptionType parameter variable


contains code to gracefully handle the exception type listed in the parameter list


All of these