Java fundamental midterm

Section 2

1. In Alice, objects inherit the characteristics of their:
Class (*)

2. A textual storyboard helps the reader understand the actions that will take place during the animation. True or false?
True (*)

3. In Alice, if a procedure is declared for a clownFish class, which classes can use the procedure?
ClownFish class (*)

4. Alice uses built-in math operators. They are:
All of the above (*)

5. In Alice, which of the following programming statements moves the alien backward the distance to the asteroid, minus 2 meters?
this.Alien move backward {this.Alien getDistanceTo this.Asteroid -2} (*)

6. You have a Class representing Cat. Each Cat can meow, purr, catch mice, and so on. When you create a new cat, what is it called?
An instance (*)

7. Which of the following statements about methods is false?
Classes must be defined directly within a method definition. (*)

8. From your Alice lessons, built-in functions provide precise property details for the following areas:
Proximity, size, spatial relation, and point of view. (*)

9. From your Alice lessons, what is the purpose of nesting?
To add visual structure to your program. (*)

10. Debugging is the process of finding bugs in a software program. True or false?
True (*)

11. A loop can be infinite (continue forever) or conditional (stops upon a condition). True or false?
True (*)

12. When you import a class from another file you have to import the entire class. True or false?
False (*)

13. To save a class to the myClasses directory you do so at the ________ level.
Class (*)

14. Which handle style would be used to rotate an object's sub-part about the x, y, and z axes?
Rotation (*)

15. Which is an example of the Boolean variable type?
True or False (*)

16. In Java code the { } brackets are used to represent what statements?
(Choose all correct answers)
Begin(*)
End(*)

17. In Alice, which of the following is not a control statement?
Move (*)

18. In Alice, a computer program requires functions to tell it how to perform the procedure. True or false?
False (*)

19. In Alice, the setVehicle procedure will associate one object to another. True or false?
True (*)

20. In Alice, where are arithmetic operators available?
(Choose all correct answers)
Amount argument (*)
Duration argument (*)
Get Distance functions (*)



22. What is the purpose of a function in Alice?

To compute and answer a question about an object. (*)

23. Which of the following elements of the Alice animation should be tested before the animation is considered complete?
All of the above. (*)

24. The Alice animation should be tested throughout development, not just at the end of the animation's development. True or false?
True (*)

Section 3

25. To execute a method in your Greenfoot game, where is it called from?
The act method (*)

26. Which one of the following can be used to detect when 2 actors collide?
isTouching() (*)

27. The list below displays components of the Greenfoot source code editor except one. Which one
should be removed?
Instance creator (*)

28. From your Greenfoot lessons, where do you review a class's inherited methods?
Documentation (*)

29. In Greenfoot, you must first create an instance before you create a class. True or false?
False (*)

30. Which of the following are examples of default superclasses that are present in a new Greenfoot scenario?
(Choose all correct answers)
World (*)
Actor (*)

31. Using the Greenfoot IDE, when is a constructor automatically executed?
When a new instance of the class is created. (*)

32. In Greenfoot, actor constructors can be used to create images or values and assign them to the variables. True or false?
True (*)

33. In Greenfoot, which method is used to add a new instance to a scenario when the world is initialized?
addObject (*)

34. When a Greenfoot code segment is executed in an if-statement, each line of code is executed in sequential order. True or false?
True (*)

35. From your Greenfoot lessons, which of the following comparison operators represents "greater than"?
>(*)

36. From your Greenfoot lessons, which axes define an object's position in a world?
(Choose all correct answers)
Y(*)
X(*)

37. Which of the following comparison operators represents "greater than or equal"?
>= (*)

38. Which of the following features of Greenfoot will locate syntax errors in your program?
Compilation (*)

39. When designing a game in Greenfoot, it helps to define the actions that will take place in a textual storyboard. True or false?
True (*)

40. In Greenfoot, a local variable is declared at the beginning of a class. True or false?
False (*)

41. Which of the following is an example of string concatenation?
Instead of entering ".png" after each image file name, add + ".png" after the imageName value in the programming statement. (*)

42. In Greenfoot, when is a local variable most often used?
Within loop constructs (*)

43. An array is an object that holds multiple methods. True or false?
False (*)

44. In Greenfoot, you can only interact with the scenario using a keyboard.
False (*)

45. Greenfoot has tools to record sound. True or false?
True (*)

46. In Java what is casting?
When you take an Object of one particular type and turn it into another Object type. (*)

47. Using the Greenfoot IDE, only five instances can be added to a scenario. True or false?
False (*)

48. In Greenfoot, which of the following options are not possible when associating an image file with an instance?
Add a video (*)

49. In Greenfoot, methods can be called in the act method. When the Act button is clicked in the environment, the methods in the method body of the act method are executed. True or false?
True (*)

50. In the Greenfoot IDE, an instance's position is on the x and y coordinates. True or false?
True (*)

Section 2

1. In Alice, when using the getDistanceTo function what menu option would you use to subtract a set value from the distance?
Math (*)

2. From your Alice lessons, if you examined a science process that had many steps, which of the following is a way that you could apply functional decomposition to this process?

1. Identify the high level steps for the science concept.
2. Further refine and define the tasks needed for each high level step.
3. Present the problem as an animation. (*)

3. When presenting your Alice animation, it is not important to give the audience a reason to listen to the presentation. True or false?
False (*)

4. Identify an example of an Alice expression.
12 + 15 = 27 (*)

5. Alice uses built-in math operators; they are:
All of the above (*)

6. From your Alice lessons, what does the Count control statement do?
Executes statements a specific number of times. (*)

7. Which of the following is not a relational operator?
//(*)

8. In Java, which symbol is used to assign one value to another?
==(*)

9. When you import a class from another file you have to import the entire class. True or false?
False(*)

10. An event is any action initiated by the user that is designed to influence the programﾒs execution during play.
True(*)

11. What do lines 9 and 11 do in the following code
Accept user input and store them in the variables num1 and num2. (*)

12. Main is an example of what in the following code?

public static void main (String[] args) {
System.out.println{"Hello World!");
}
A method (*)

13. A flowchart is a useful way to illustrate how your Alice animation's characters will look. True or false?
False (*)

14. From your Alice lessons, a flowchart could be created in a software program, or documented in a journal. True or false?
True(*)

15. From your Alice lessons, what does inheritance mean?
Each subclass inherits the methods and properties of its superclass. (*)

16. What do moving objects provide to your scene?
The action (*)

17. A conditional loop is a loop that will continue forever. True or false?
False (*)

18. Which of the following actions would require a control statement to control animation timing?
(Choose all correct answers)
A bird flying. (*)
A fish swimming. (*)
 biped object walking. (*)

19. In Alice, which of the following is not a control statement?
Move (*)

20. In Alice, which control statement is used to invoke simultaneous movement?
Do Together (*)

Java Fundamental Section 7

1. Static classes can't return instances of the parent class when the parent class uses a private constructor. True or false?

False (*)

2. Static methods can't act like "setter" methods. True or false?

False (*)

3. Static methods can read static variables. True or false?

True (*)

4. What is Polymorphism?

The concept that a variable or reference can hold multiple types of objects. (*)

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

HousePet Scooby = new Dog();

Yes, because polymorphism allows this since Dog is a subclass of HousePet. (*)

6. Why would a programmer use polymorphism rather than sticking to a standard array?

Because arrays only work using the same object type and polymorphism provides a way around this. (*)

7. The constructor of a class has the same name as the class. True or false?

True (*)

8. Which of the following may be part of a class definition?

all of the above (*)

9. What operator do you use to call an object's constructor method and create a new object?

New (*)

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

True (*)

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

super.needOil(); (*)

12. What is the Java Applet?

(Choose all correct answers)

A web-based Java program that is embedded into a web browser. (*)

A graphic visual included in Java. (*)

13. Which of the following is a possible way to overload constructors?

 

14. Which of the following could be a reason to return an object?

The method makes changes to the object and you wish to continue to use the updated object outside of the method. (*)

15. Consider the following:

There is a method A that calls method B. Method B is a variable argument method. 

With this, which of the following are true?

(Choose all correct answers)

Method A can invoke method B twice, each time with a different number of arguments. (*)

When invoked, method B creates an array to store some or all of the arguments passed to it from method A. (*)

1. It is possible to inherit from an abstract class. True or false?

True (*)

2. If a class is immutable then it must be abstract. True or false?

False (*)

3. Which of the following would be most beneficial for this scenario?

Joe is a college student who has a tendency to lose his books. Replacing them is getting costly. In an attempt to get organized, Joe wants to create a program that will store his textbooks in one group of books, but he wants to make each book type the subject of the book (i.e. MathBook is a book). How could he store these different subject books into a single array?

Using polymorphism. (*)

4. Static classes can exist as stand alone classes. True or false?

False (*)

5. Public static variables can't have their value reset by other classes. True or false?

False (*)

6. A static variable is always publicly available. True or false?

False (*)

7. Which of the following correctly defines overloading?

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

8. A team is working on a coding project. They desire that all portions of their code should have access to the classes that they write. What access modifier should be used for each class?

Public (*)

9. It is possible to overload a method that is not a constructor. True or False?

True (*)

 

10. What value will be returned when the setValue method is called?

37(*)

11. A class can only have one constructor. True or false?

False (*)

12. The following statement compiles and executes. What do you know for certain? 

tree.grows(numFeet);

grows must be the name of a method. (*)

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

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. (*)

14. Which of the following correctly describes an "is-a" relationship?

A helpful term used to conceptualize the relationships among nodes or leaves in an inheritance hierarchy. (*)

15. It is possible for a subclass to be a superclass. True or false?

True (*)

Java fundamental section 6

1. The following array declaration is valid. True or false?

int[] y = new int[5];
True (*)

2. double array[] = new double[8];

After execution of this statement, which of the following are true?
array.length is 8 (*)

3. The following array declaration is valid:

int[] y = new int[5];
True (*)

4. The following creates a reference in memory named z that can refer to seven different doubles via an index. True or false?

double z[] = new double[7];
True (*)

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

double[][] a=new double[4][5];
True (*)

6. Which of the following statements print every element of the one dimensional array prices to the screen?
for(int i=0; i < prices.length; i++){System.out.println(prices[i]);} (*)

7. The following segment of code initializes a 2 dimensional array of references. True or false?

String[][] array={{"a", "b", "C"},{"a", "b", "c"}};
True (*)

8. Which of the following statements adds 5 to every element of the one dimensional array prices and then prints it to the screen?

for(int i=0;i<prices.length;i++)
System.out.println(prices[i]+5); (*)

9. What is the output of the following segment of code if the command line arguments are "a b c d e f"?

6 (*)

10. The following array declaration is valid. True or false?
int k[] = new int[10];
True (*)

11. If an exception is thrown by a method, where can the catch for the exception be?
The catch can be in the method that threw the exception or in any other method that called the method that threw the exception. (*)

12. Which of the following could be a reason to throw an exception?
To eliminate exceptions from disrupting your program. (*)

13. Choose the best response to this statement: An error can be handled by throwing it and catching it just like an exception.
False. An error is much more severe than an exception and cannot be dealt with adequately in a program. (*)

14. A computer company has one million dollars to give as a bonus to the employees, and they wish to distribute it evenly amongst them.

The company writes a program to calculate the amount each employee receives, given the number of employees.

Unfortunately, the employees all went on strike before they heard about the bonus. This means that the company has zero employees.

What will happen to the program if the company enters 0 into the employment number?
(Choose all correct answers)

An exception will occur because it is not possible to divide by zero. (*)

15.  What are exceptions used for in Java?
Correcting mistakes made in your code and handling extraordinary cases. (*)


1.  Which line of code shows the correct way to throw an exception?
throw new Exception("Array index is out of bounds"); (*)

2. It is possible to throw and catch a second exception inside a catch block of code. True or false?
True (*)

3. What exception message indicates that a variable may have been mispelled somewhere in the program?
variableName cannot be resolved to a variable (*)

4. Choose the best response to this statement: An error can be handled by throwing it and catching it just like an exception.
False. An error is much more severe than an exception and cannot be dealt with adequately in a program. (*)

5. A computer company has one million dollars to give as a bonus to the employees, and they wish to distribute it evenly amongst them.

The company writes a program to calculate the amount each employee receives, given the number of employees.

Unfortunately, the employees all went on strike before they heard about the bonus. This means that the company has zero employees.

What will happen to the program if the company enters 0 into the employment number?
(Choose all correct answers)
An exception will occur because it is not possible to divide by zero. (*)

6. Which of the following declares and initializes a two dimensional array that can hold 6 Object reference types?
Object[][] array=new Object[2][3]; (*)

7. What is the Output of the following segment of code?

666666 (*)

8. The following creates a reference in memory named k that can refer to six different integers via an index. True or false?

int k[]= int[6];
False (*)

9. Which of the following declares a one dimensional array name scores of type int that can hold 14 values?

int[] scores=new int[14]; (*)

10. 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]);
963 (*)

11. The following creates a reference in memory named z that can refer to seven different doubles via an index. True or false?

double z[] = new double[7];
True (*)

12. The following array declaration is valid:

int[] y = new int[5];
True (*)

13. Which of the following declares and initializes a one dimensional array that can hold 5 Object reference types?
Object array=new Object[5]; (*)

Java Fundamental Section 5

1.  What will print if the following Java code is executed?

if ((5.1 > 4.3 && 6.2 < 8.4) && !(7.2 < 3.5 || 1.2 == 2.1 || 2.2 != 2.25))
System.out.print("TRUE");
else
System.out.print("FALSE");
False (*)

2.  What is the difference between the symbols = and == ?
The = is use to assign values to variables and the == compares values. (*)

3.  Consider that a Scanner has beeLabel
n initialized such that:

Scanner in = new Scanner(System.in);

Which of the following lines of code reads in the userﾒs input and sets it equal to a new String called input?
String input = in.next(); (*)

4.  In Java, each case seqment of a switch statement requires the keyword break to avoid "falling through".
True (*)

5.  Which of the following could be a reason to use a switch statement in a Java program?
Because it allows the program to run certain segments of code and neglect to run others based on the input given. (*)

6.  Which of the following correctly matches the switch statement keyword to its function?
(Choose all correct answers)
default: signals what code to execute if the input does not match any of the cases (*)

case: signals what code is executed if the user input matches the specified element (*)
switch: identifies what element will be compared to the element of the case statements to find a possible match (*)

7.  The three logic operators in Java are:

&&, ||, ! (*)

8.  The following code fragment properly implements the switch statement. True or false?

default(input)
switch '+':
answer+=num;
break;
case '-':
answer-=num;
break;
!default
System.out.println("Invalid input");
False (*)

9.  What is a loop?
A set of logic that is repeatedly executed until a certain condition is met. (*)

10.  One advantage to using a while loop over a for loop is that a while loop always has a counter. True or false?
False (*)

11.  The syntax below represents a valid initialization of a for loop counter. True or False?

public class ForLoop {
 public static void main (String args[])
 {
  for (int i=10; i <20; i++)
  {System.out.println("i: "+i); }
 }
}
True (*)

12.  What is one significant difference between a while loop and a do-while loop?
A DO-WHILE loop will always execute the code at least once, even if the conditional statement for the WHILE is never true. A WHILE loop is only executed if the conditional statement is true. (*)

13.  Identify which situation could be an example of a while loop.
All of the above. (*)

14.  Which of the following are types of loops in Java?

(Choose all correct answers)
while (*)
for (*)
do-while (*)

15.  In a for loop, the counter is automatically incremented after each loop iteration. True or False?
False (*)

1.  In an if-else construct, the condition to be evaluated must be contained within parentheses. True or False?
True (*)

2.  Which of the following are relational operators in Java?

(Choose all correct answers)
< (*)
<= (*)
!= (*)

3.  Which of the following correctly initializes an instance of Scanner, called "in", that reads input from the console screen?

Scanner in = new Scanner(System.in); (*)

4.  Which of the following correctly matches the switch statement keyword to its function?
(Choose all correct answers)
default: signals what code to execute if the input does not match any of the cases (*)
switch: identifies what element will be compared to the element of the case statements to find a possible match (*)
case: signals what code is executed if the user input matches the specified element (*)

5.  Which of the two diagrams below illustratethe correct syntax
for variables used in an if-else statement?

Example A(*)

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

if (gender == "male")
System.out.print("Mr.");
else
System.out.print("Ms.");
System.out.print( (gender == "male") ? "Mr." : "Ms." ); (*)

7.  In an if-else construct the condition to be evaluated must end with a semi-colon. True or false?
False (*)

8.  This keyword is used to instruct specific code when the input for a switch statement that does not match any of the cases.
Default(*)

9.  What is the output of the following code segment?

int num = 7;
while(num >= 0)
{
num -= 3;
}
System.out.println(num);
-2 (*)

10.  What should replace the comment "//your answer here" in the code below if the code is meant to take no action when i % 2 is 0 (in other words when i is even)?

for(int i = 0; i < 10; i++){
if(i%2 == 0)
//your answer here
else
k+=3;
}
Continue (*)

11.  What is one significant difference between a while loop and a do-while loop?
A DO-WHILE loop will always execute the code at least once, even if the conditional statement for the WHILE is never true. A WHILE loop is only executed if the conditional statement is true. (*)

12.  A counter used in a for loop cannot be initialized within the For loop statement. True or False?
False (*)

13.  In a for loop the counter is not automatically incremented after each loop iteration. Code must be written to increment the counter. True or false?
True (*)

14.  One advantage to using a while loop over a for loop is that a while loop always has a counter. True or false?
False (*)

15.  When the for loop condition statement is met the construct is exited. True or false?
False (*)

Java Fundamental Section 4

1.  Which of the following is not correct Java code?
double x=Math.pow; (*)

2.  Which of the following statements correctly assigns "3 times 10 to the 4th power" to the variable number?
double number=3e4; (*)

3.  Select the declaration and initialization statement that will hold the letter J.
char letter='J'; (*)

4.  What two values can a boolean variable have?
True and false (*)

5.  What will the method methodA print to the screen?

1.Public ClassA {
2.Int g=5; // global variable
3.Public void methodA() {
4.Int g=6 // local variable
5.System.out.println (g*3);
6.}
7.}
18 (*)


6.  A workspace can not have more than one stored projects. True or false?
False (*)

7.  A perspective is described as:
None of the above

8.  For every opening curly brace { there does not need to be a closing curly brace} for the program to compile without error. True or False?
False (*)

9.  The following defines a class keyword:
Precedes the name of the class. (*)

10.  Which of the two diagrams below illustrate the general form of a Java program?

Example B (*)

11.  The following defines an import keyword:
Provides the compiler information that identifies outside classes used within the current class. (*)

12.  When importing another package into a class you must import the entire package as well as the package classes that will be called. True or False?
False (*)

13.  Which of the following creates a String named Char?
String Char; (*)

14.  The String methods equals and compareTo perform similar functions and differ in their return type. True or false?
True (*)

15.  Declaring and instantiating a String is much like any other type of variable. However, once instantiated, they are final and cannot be changed. True or false?
True (*)


1.  Which of the following is not correct Java code?
double x=Math.pow; (*)

2.  Which of the following statements correctly assigns "3 times 10 to the 4th power" to the variable number?
double number=3e4; (*)

3.  Select the declaration and initialization statement that will hold the letter J.
char letter='J'; (*)

4.  What two values can a boolean variable have?
True and false (*)

5.  What will the method methodA print to the screen?

1.Public ClassA {
2.Int g=5; // global variable
3.Public void methodA() {
4.Int g=6 // local variable
5.System.out.println (g*3);
6.}
7.}
18 (*)


1.  A combination of views and editors are referred to as _______________.
A perspective (*)

2.  You can return to the Eclipse Welcome Page by choosing Welcome from what menu?
Help (*)

3.  When converting gallons to liters its best to put the calculation result into a variable with a _______________ data type.
Double(*)

4.  Which of the following is the name of a Java primitive data type?
Int(*)

5.  Which of the following declarations are correct?

(Choose all correct answers)
double duty; (*)
float loan; (*)

6.  Select the declaration and initialization statement that will hold the letter J.
char letter='J'; (*)

7.  Which of the following examples of Java code is not correct?
boolean b=1; (*)

8.  Which of the following statements correctly assigns "3 times 10 to the 4th power" to the variable number?
double number=3e4; (*)


9. The following program prints "Not Equal":

True or false?
 True (*)


10.  Consider the following code snippet

String forest = new String("Black");
System.out.println(forest.length());

What is printed?
5 (*)

11.  Suppose that s1 and s2 are two strings. Which of the statements or expressions are valid?
(Choose all correct answers)

int m = s1.length(); (*)
String s3 = s1 + s2; (*)
s1.compareTo(s2); (*)

12.  The following defines a class keyword:
Precedes the name of the class. (*)

13.  When importing another package into a class you must import the entire package as well as the package classes that will be called. True or False?
False (*)

14. Which of the two diagrams below illustrate the general from a
Java program?

Example B (*)

15.  Which of the following defines a driver class?
Contains a main method and other static methods. (*)

Java Fundamental Section 3 L6-L10

1.  In Greenfoot you can interact with the scenario using a mouse.
True (*)
2.  In Greenfoot, which method checks if a key on the keyboard has been pressed?
isKeyDown method (*)
3.  Greenfoot has tools to record sound. True or false?
True (*)
4.  A collision in Greenfoot is when two actors make contact?
True (*)
5.  From your Greenfoot lessons, how do you call a defined method?
Call the method from the act method. (*)
6.  In Greenfoot, defined methods must be used immediately. True or false?
False (*)
7.  Which of the following is an example of string concatenation?
Instead of entering ".png" after each image file name, add + ".png" after the imageName value in the programming statement. (*)
8.  In Greenfoot, what type of symbol is used to connect boolean expressions?
Logic operators (*)
9.  Which of the following is not a component of a while loop?

if statement (*)
10.  Which of the following answers have the correct syntax for declaring a class variable in Greenfoot?
(Choose all correct answers)
public variable-type variable-name; (*)
private variable-type variable-name; (*)
11.  Where can we review the available classes and methods in Greenfoot, including the stop method?
Greenfoot Application Programmers' Interface (API) (*)
12.  From your Greenfoot lessons, what is the parameter of the following constructor that creates a new image, and designates it to the Actor class?

setImage (new GreenfootImage("Bee01.png"));
Bee01.png (*)
13.  Abstraction occurs in many different ways in programming. True or false?
True (*)
14.  From your Greenfoot lessons, which one of the following is an example of when an abstraction technique is used?
Passing a paramater in a constructor to set an initial speed. (*)
15.  In Greenfoot, you can cast an Actor class to a World class?
False (*)

Java Fundamental Section 2 L8-L14

1.  The condition in a WHILE loop is a boolean expression. True or false?
True (*)
2.  What do lines 7, 10 and 13 do in the following code?

Print "A","B", and the value of num3 on the screen (*)

3.  Which of the following IF control structures command the blue tang fish to roll and simultaneously move down if it collides with a shark, or move forward if it does not collide with a shark?

4.  In Alice, you must place the control structure in the code editor before adding any code that will go within it. True or false?
False (*)
5.  Variable values can be changed as often as you like. True or false?
True (*)
6.  When viewing the Java Code on the side in Alice, you can change the Java code directly instead of the Alice code. True or false?
False (*)
7.  In Alice, which of the following programming statements moves the cat backward, half the distance to the bird?
this.Cat move backward {this.Cat getDistanceTo this.Bird / 2} (*)
8.  An example of an expression is:
3*3=9 (*)
9.  If the value already exists in the variable it is overwritten by the assignment operator (=). True or false?
True (*)
10.  Which of the following does not describe variables?
Arranged in rows and columns. (*)
11.  Alice provides pre-populated worlds through which new menu tab?
Starters (*)
12.  Which one of the following event listener types is not available at the top-level of the addEvent drop down list in Alice?
Collision (*)
13.  In Alice, what are the forms of a scenario?
A task to perform. (*)

A problem to solve. (*)
14.  When presenting your Alice animation, ensure that your presentation is thoroughly tested and complete. True or false?
True (*)
15.  In Alice, as part of the recording process you can demonstrate the events that are programmed within your animation. True or false?
True (*)