final test of maria.docx

Test: Java Fundamentals Final ExamReview your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer.

Section 4

(Answer all questions in this section)

1. Which of the following statements displays 12345?

I. System.out.println( 123 * 100 + 45);II. System.out.println("123" + 45);III. System.out.println( 12 + "345");

Mark for

Review (1) Points

All of the above. (*)

I only.

I and II only.

II and III only.

None of the above.

Incorrect. Refer to Section 4 Lesson 3.

2. What is the output of the following lines of code?

int j=6,k=8,m=2,result;result=j-k%3*m; System.out.println(result);

Mark for

Review (1) Points

6

0

-42

2 (*)


3. Four variables are required to support a conversion of one unit of measure to another unit of measure. True or False? Mark for

Review (1) Points

True

False (*)

Correct

4. You can return to the Eclipse Welcome Page by choosing Welcome from what menu? Mark for

Review (1) Points

File

Edit

Help (*)

Close

Correct

5. A perspective is described as: Mark for

Review (1) Points

A combination of views and editors (*)

A combination of views and windows

A combination of editor tabs

None of the above

Correct


Section 4


6. In Eclipse, when you run a Java Application, the results are displayed in a new window. True or False? Mark for

Review (1) Points

True

False (*)


7. You need to _______________ Java code to generate a .class file Mark for

Review (1) Points

Collect

Compile (*)

Package

Assemble

Correct

8. Which of the two diagrams below illustrate the general form of a Java program? Mark for

Review

(1) Points

Example A

Example B (*)

Correct

9. Which of the following defines an object class? Mark for

Review (1) Points

Contains a main method and other static methods.

Contains classes that define objects. (*)

Contains a main method, a package, static methods, and classes that define objects.None of the above.

Correct

10.

Which of the following creates a String named Char? Mark for

Review (1) Points

char string;

String Char; (*)

char Char;

char char;

String char;

Correct


Section 4


11.

What is printed by the following code segment? Mark for

Review (1) Points

alligator (*)

albatross alligator

albatross

a1

Correct

12.

The following program prints "Not Equal". True or false? Mark for

Review (1) Points

True

False (*)


13.

The following code is an example of creating a String reference:

String s;

True or false?

Mark for

Review (1) Points

True (*)

False


14.

The == operator can be used to compare two String objects. The result is always true if the two strings are have the exact same characters in each position of the String. True or false?

Mark for

Review (1) Points

True

False (*)

Correct

Section 5


15.

How would you use the ternary operator to rewrite this if statement?

if (gender == "female") System.out.print("Ms.");elseSystem.out.print("Mr.");

Mark for

Review (1) Points

System.out.print( (gender == "female") ? "Mr." : "Ms." );

System.out.print( (gender == "female") ? "Ms." : "Mr." ); (*)

(gender == "female") ? "Mr." : "Ms." ;

(gender == "female") ? "Ms." : "Mr." ;

Correct


Section 5


16. Which of the following are relational operators in Java? Mark for

Review (1) Points

(Choose all correct answers)

< (*)

<= (*)

=

!= (*)

All of the above.

Correct

17. How would you use the ternary operator to rewrite this if statement?

if (balance < 500)<fee = 10;elsefee = 0;

Mark for

Review (1) Points

fee = ( balance < 500) ? 0 : 10;

fee= ( balance < 500) ? 10 : 0; (*)

fee = ( balance >= 5) ? 0 : 10;

fee = ( balance >= 500) ? 10 : 0;

fee = ( balance > 5) ? 10 : 0;


18. One advantage to using a while loop over a for loop is that a while loop always has a counter. True or false? Mark for

Review (1) Points

True

False (*)

Correct

19. A counter used in a for loop cannot be initialized within the For loop header. True or false? Mark for

Review (1) Points

True

False (*)

Correct

20. When the for loop condition statement is met the construct is exited. True or false? Mark for

Review (1) Points

True

False (*)

Correct


Section 6


21. Big-O Notation is used in Computer Science to describe the performance of Sorts and Searches on arrays. True or false? Mark for

Review (1) Points

True (*)

False

Correct

22. Which of the following best describes lexicographical order? Mark for

Review (1) Points

A simple sorting algorithm that is inefficient on large arrays.

An order based on the ASCII value of characters. (*)

A complex sorting algorithm that is efficient on large arrays.

The order of indicies after an array has been sorted.

Correct

23. Which of the following sorting algorithms utilizes a "divide and conquer" technique to sort arrays with optimal speed? Mark for

Review (1) Points

Sequential Search

Merge Sort (*)

Selection Sort

Binary Search

All of the above

Correct

24. A sequntial search is an iteration through the array that stops at the index where the desired element is found. True or false? Mark for

Review (1) Points

True (*)

False

Correct

25. Suppose you misspell a method name when you call it in your program. Which of the following explains why this gives you an exception?

Mark for

Review (1) Points

Because the parameters of the method were not met.

Because the interpreter does not recognize this method since it was never initialized, the correct spelling of the method was initialized.Because the interpreter tries to read the method but when it finds the method you intended to use it crashes.This will not give you an exception, it will give you an error when the program is compiled. (*)

Correct


Section 6


26.

What is the output of the following segment of code? Mark for

Review (1) Points

456789

777777 (*)

555555

987654

This code doesn't compile.

Correct

27.

Which of the following declares and initializes a two dimensional array that can hold 6 Object reference types? Mark for

Review (1) Points

String[] array=new String[6];

Object array=new Object[6];

Object[][] array=new Object[2][3]; (*)

String[][] array=String[6];

Correct

28.

The following segment of code initializes a 2 dimensional array of primitive data types. True or false?

double[][] a=new double[4][5];

Mark for

Review (1) Points

True (*)

False


29.

What is the output of the following segment of code?

int num[]={9,8,7,6,5,4,3,2,1}; for(int i=0;i<9;i=i+3) System.out.print(num[i]);

Mark for

Review (1) Points

9630

963 (*)

987654321

97531

This code doesn't compile.

Correct

Section 7


30.

Which of the following creates an object from the Animal class listed below: Mark for

Review (1) Points

Animal cat=new Animal();

Animal cat=Animal(50,30);

Animal cat=new Animal(50,30); (*)

Animal cat=new Animal(50);

Correct


Section 7


31.

What value will return for j when the setValue method is called? Mark for

Review (1) Points

31

32

10

11 (*)

Correct

32.

The basic unit of encapsulation in Java is the primitive data type. True or false? Mark for

Review (1) Points

True

False (*)

Correct

33.

What is wrong with the following class declaration?

class Account{ ; private int number; private String name;; public Account; }

Mark for

Review (1) Points

Classes cannot include strings.

Classes cannot include mixed data types.

The constructor method has no definition. (*)

There is nothing wrong.

Correct

34.

Which of the following calls the method calculate correctly? Mark for

Review (1) Points

ThisClass t=new ThisClass(); int x=t.calculate(3,4); (*)

int x=calculate(3,4);

ThisClass t=new ThisClass(); int x=t.calculate(3);

ThisClass t=new ThisClass(); int x=t.calculate();


35.

A constructor is used to create objects. True or false? Mark for

Review (1) Points

True (*)

False

Correct


Section 7


36. Which segment of code correctly defines a method that contains two objects of class Tree as parameters? Mark for

Review (1) Points

void bloom(Tree pine, Tree oak) {//code here }; (*)

Tree bloom (pine, oak) {//code here };

void bloom, Tree pine, Tree oak {//code here };

None of the above, objects cannot be passed as parameters.


37. Which of the following could be a reason to return an object? Mark for

Review (1) Points

Because you wish to be able to use that object inside of the method.

It has faster performance than returning a primitive type.

The method makes changes to the object and you wish to continue to use the updated object outside of the method. (*)None of the above. It is not possible to return an object.

Correct

38. Which of the following is the definition of a constructor? Mark for

Review (1) Points

A keyword that specifies accessibility of code.

A special method that is used to assign initial values to instance variables in a class. (*)

A way to call a method with a variable number of arguments using an elipse.

A variable in a method declaration that gets passed into the method.

Correct

39. Which of the following is the definition for a variable argument method? Mark for

Review (1) Points

A way to create a new class.

Specifies accessibility to code.

Having more than one constructor with the same name but different arguments.

A type of argument that enables calling the same method with a different number of arguments. (*)

Correct

40. Which of the following is the correct way to code a method with a return type an object Automobile? Mark for

Review (1) Points

Automobile upgrade(String carA){ carA="Turbo"; return carA;}Automobile upgrade(Automobile carA){ carA.setTurbo("yes");

return carA;} (*)String upgrade(String carA){ carA="Turbo"; return carA;}upgrade(Automobile carA) Automobile{ carA.setTurbo("yes"); return carA;}None of the above. It is not possible to return an object.

Correct


Section 7


41. Why is it not possible to extend more than one class at a time in an inheritance hierarchy chain? Mark for

Review (1) Points

It is not necessary considering all public content is passed from super class to subclass and further to their subclass and that subclass' subclass and so on. (*)Because the computer cannot handle code that complex.

To prevent confusion for the programmer.

It is possible to extend more than one class at a time.

Correct

42. Why are hierarchies useful for inheritance? Mark for

Review (1) Points

They keep track of where you are in your program.

They restrict a superclass to only have one subclass.

They organize constructors and methods in a simplified fashion.

They are used to organize the relationship between a superclass and its subclasses. (*)


43. An access modifier is a keyword that allows subclasses to access methods, data, and constructors from their parent class. True or false?

Mark for

Review (1) Points

True (*)

False

Correct

44. Which of the following is the correct way to call an overriden method needOil() of a super class Robot in a subclass SqueakyRobot?

Mark for

Review (1) Points

Robot.needOil(SqueakyRobot);

SqueakyRobot.needOil();

super.needOil(); (*)

needOil(Robot);


45. Consider the following method of the class Test:

public static List returnList(List list){return list;}

Which of the following program segments in Test's client class will compile with no errors?

I. List nums = new ArrayList();nums = Test.returnList(nums);

Mark for

Review (1) Points

II. ArrayList nums = new ArrayList(); nums = Test.returnList(nums);III. ArrayList nums1 = new ArrayList();List nums2 = Test.returnList(nums1);

I only

I and III (*)

II only

II and III

I, II, and III

Correct


Section 7


46. What does it mean to override a method? Mark for

Review (1) Points

It is a way to create multiple methods with the same name but different parameters.It allows an array to contain different object types.

It restricts the privacy of the method to only be accessible from inside the same class.It is a way of redefining methods of a parent class inside the child class, with the same name, parameters, and return type. (*)


47. Would this code be correct if a Dog is a HousePet? Why or Why not?

HousePet Scooby = new Dog();

Mark for

Review (1) Points

Yes, because it is an abstract class.

Yes, because polymorphism allows this since Dog is a subclass of HousePet. (*)No, because ref must be declared either a HousePet or a Dog, but not both.

Maybe. There is no way to tell without seeing the methods for Dog and the methods for HousePet.

Correct

48. The base case condition can work with a constant or variable. True or false? Mark for

Review (1) Points

True (*)

False

Correct

49. Static methods can't change any class variable values at run-time. True or false? Mark for

Review (1) Points

True

False (*)

Correct

50. Non-final static class variables should be private to prevent changes from other classes. True or false? Mark for

Review (1) Points

True (*)

False

Correct

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final test of maria.docx