Java - Final Review
When one object is a specialized version of another object, there is this type of relationship between them. 1) "has a" 2) "is a" 3) direct 4) "contains a"
"is a"
In UML diagrams, this symbol indicates that a member is public. 1) / 2) @ 3) - 4) +
+
By default, Java initializes array elements with what value? A) 0 B) 100 C) 1 D) -1
0
Java automatically stores this value in all uninitialized static member variables: 1) 0 2) -1 3) null 4) false
0
If final int SIZE = 15 and int[] x = new int[SIZE], what would be the range of subscript values that could be used with x[]? - 1 through 15 - 1 through 14 - 0 through 14 - 0 through 15
0 through 14
Look at the following declaration:enum Tree { OAK, MAPLE, PINE }What is the ordinal value of the MAPLE enum constant? 1) 0 2) 1 3) 2 4) 3 5) Tree.MAPLE
1
Which of the following statements will create a reference, str, to the string, "Hello, world"? Option-1String str = new String("Hello, world"); Option-2String str = "Hello, world"; 1) 1 2) 2 3) 1 and 2 4) neither 1 or 2
1 and 2
Look at the following code. The method in line ________ will override the method in line ________. Line 1public class ClassA Line 2{ Line 3public ClassA() {} Line 4public int method1(int a){} Line 5public int method2(int b){} Line 6} Line 7public ClassB extends ClassA Line 8{ Line 9public ClassB(){} Line 10public int method1(int b){} Line 11public int method2(double c){} Line 12} 1) 4, 10 2) 5, 11 3) 10, 4 4) 11, 5 5) Both A and B
10, 4
What will be returned from the following method? public static double method() { double a = 8.5 + 9.5; return a; } - 18.0 - 18 (as an integer) - 8 - This is an error.
18.0
What will be the value of x[8] after the following code has been executed? final int SUB = 12; int[] x = new int[SUB]; int y = 100; for (int i = 0; i < SUB; i++) { x[i] = y; y += 10; } - 170 - 180 - 190 - 200
180
What will be the value of x[1] after the following code is executed? int[] x = {22, 33, 44}; arrayProcess(x[1]); .... public static void arrayProcess(int a) { a = a +5; } A) 27 B) 33 C) 38 D) 49
33
What will be the value of x[1] after the following code is executed? int[] x = {22, 33, 44}; arrayProcess(x); ...... for (int k = 0; k < 3: k++) { a[k] = a[k] + 5; } - 27 - 33 - 38 - 49
38
Look at the following code. Which line has an error? Line 1public interface Interface1 Line 2{ Line 3int FIELDA = 55; Line 4public int methodA(double){} Line 5} 1) 1 2) 2 3) 3 4) 4
4
Given the following code, what will be the value of finalAmount when it is displayed? A) 528.00 B) 580.00 C) 522.00 D) There is no value because the object order has not been created.
522.00
What will be the value of x[8] after the following code has been executed? final int SUB = 12; int[] x = new int[SUB]; int y = 20; for (int i = 0; i < SUB; i++) { x[i] = y; y += 5; } - 50 - 55 - 60 - 65
60
Look at the following code. Which line in ClassA has an error? Line 1public interface MyInterface Line 2{ Line 3int FIELDA = 55; Line 4public int methodA(double); Line 5} Line 6public class ClassA implements MyInterface Line 7{ Line 8FIELDA = 60; Line 9public int methodA(double) { } Line 10} 1) 6 2) 7 3) 8 4) 9
8
What is the value of scores[2][3] in the following array? int[][] scores = { {88,80,79,92}, {75, 84, 93, 80}, {98, 95, 92, 94}, {91, 84, 88, 96} }; - 94 - 84 - 93 - 95
94
This annotation tells the Java compiler that a method is meant to override a method in the superclass. 1) @Override 2) @Overload 3) @Protected 4) @Inherited
@Override
When writing the documentation comments for a method, you can provide a description of each parameter by using a: - @comment tag - @doc tag - @param tag - @return tag
@param tag
For the following code, what would be the value of str[2]? String[] str = {"abc", "def", "ghi", "jkl"}; - "ghi" - "def" - A reference to the String "ghi" - A reference to the String "def"
A reference to the String "ghi"
A protected member of a class may be directly accessed by: 1) methods of the same class 2) methods of a subclass 3) methods in the same package 4) All of the above
All of the above
In Java, it is possible to write a method that will return: 1) a whole number 2) a monetary value 3) a string of characters 4) a reference to an object 5) All of the above
All of the above
If a class contains an abstract method: 1) you cannot create an instance of the class 2) the method will have only a header, but not a body, and end with a semicolon 3) the method must be overridden in subclasses 4) All of the above
All of these
When an array is passed to a method: - a reference to the array is passed - it is passed just as an object - the method has direct access to the original array - All of these
All of these
Which of the following are classes from the Java API? - Scanner - Random - PrintWriter - All of these
All of these
Which of the following is not a way a user can interact with a computer? a) command line b) console interface c) GUI d) All of these are ways for a user to interact with a computer
All of these are ways for a user to interact with a computer
What do you normally use with a partially-filled array? - A class that does nothing but manage the array - An accompanying parallel array - An accompanying integer value that holds the number of items stored in the array - An accumulator
An accompanying integer value that holds the number of items stored in the array
What would be the result of the following code? final int ARRAY_SIZE = 5; float[] x = float[ARRAY_SIZE]; for (int I =1; I <= ARRAY_SIZE; i++) { x[i] = 10.0; } A) All the values in the array are initialized to 10.0. B) All the values, except the first, are set to 10.0. C) An error will occur when the program runs. D)There will be a compilation error.
An error will occur when the program runs.
Select all that apply. Which of the following file types are supported by the image class? a) BMP b) JPEG c) GIF d) PNG
BMP, JPEG, GIF, PNG
Select all that apply. Which of the following are constructors of the BorderPane class? a) BorderPane() b) BorderPane(top, bottom) c) BorderPane(center) d) BorderPane(left, right) e) BorderPane(center, top, right, bottom, left)
BorderPane(), BorderPane(center), BorderPane(center, top, right, bottom, left)
CRC stands for: 1) Code, Reuse, Constancy 2) Class, Responsibilities, Collaborations 3) Class, Redundancy, Collections 4) Class, Recyclability, Collaborations
Class, Responsibilities, Collaborations
Given the following code which of the following is TRUE? public class ClassB implements ClassA{} 1) ClassA must override each method in ClassB. 2) ClassB must override each method in ClassA. 3) ClassB inherits from ClassA. 4) ClassA inherits from ClassB.
ClassB must override each method in ClassA
In the following statement, which is the interface? public class ClassA extends ClassB implements ClassC 1) ClassA 2) ClassB 3) ClassC 4) Cannot tell
ClassC
If method A calls method B, and method B calls method C, and method C calls method D, when method D finishes, what happens? A) Control is returned to method A. B) Control is returned to method B. C) Control is returned to method C. D) The program terminates.
Control is returned to method C.
What is wrong with the following method call? displayValue (double x); A) There is nothing wrong with the statement. B) displayValue will not accept a parameter. C) D)
Do not include the data type in the method call.
This refers to the combining of data and code into a single object. 1) Data hiding 2) Abstraction 3) Object 4) Encapsulation
Encapsulation
True or False - A GUI program automatically stops executing when the end of the main method is reached.
False
True or False - A method that gets a value from a class's field but does not change it is known as a mutator method.
False
True or False - All methods in an abstract class must also be declared abstract.
False
True or False - An array can hold multiple values of several different data types simultaneously.
False
True or False - If a method in a subclass has the same signature as a method in the superclass, the subclass method overloads the superclass method.
False
True or False - If a[] and b[] are two integer arrays, the expression a == b compares the array contents.
False
True or False - In an inheritance relationship, the subclass constructor always executes before the superclass constructor.
False
True or False - In the method header the static method modifier means the method is available to code outside the class.
False
True or False - In the method header, the method modifier public means that the method belongs to the class, not a specific object.
False
True or False - Inheritance involves a subclass, which is the general class, and a superclass, which is the specialized class.
False
True or False - Instance methods should be declared static.
False
True or False - Java limits the number of dimensions that an array may have to 15.
False
True or False - Only constants and variables may be passed as arguments to methods.
False
True or False - The BorderPane container always displays its content in five regions which are top, bottom, left, right, and center and each region must be used.
False
True or False - The command line interface is an event-driven interface.
False
True or False - The public access specifier for a field indicates that the attribute may not be accessed by statements outside the class.
False
True or False - The term "default constructor" is applied to the first constructor written by the author of a class.
False
True or False - To display an image in a JavaFX application, you can use either the Image or ImageView class.
False
True or False - To preserve an image's aspect ratio you can use the ImageView class's PreserveAspectRatio method.
False
True or False - When a local variable in an instance method has the same name as an instance field, the instance field hides the local variable.
False
True or False - When a splash screen is displayed, the application does not load and execute until the user clicks the splash screen image with the mouse.
False
True or False - When an interface variable references an object, you can use the interface variable to call any and all of the methods in the class implementing the interface.
False
True or False - You can declare an enumerated data type inside of a method.
False
True or False - the names of the enum constants in an enumerated data type must be enclosed in quotation marks.
False
The __________ layout container arranges the contents into cells, similiar to a spreadsheet. a) GRID b) GridPane c) GridPaneObj d) CellPane
GridPane
The HBox object's setPadding method takes a(n) ___________ as it's argument. - Insets method - Insets object - boolean - integer
Insets object
Which of the following is an example of a lambda expression? 1) int x = x * factor; 2) IntCalculator = new divider(x, 2); 3) IntCalculator multiplier = x -> x * factor; 4) All of the above
IntCalculator multiplier = x -> x * factor;
Which of the following is NOT true about static methods? 1) It is necessary for an instance of the class to be created to execute the method. 2) They are created by placing the key word static after the access specifier in the method header. 3) They are called directly from the class. 4) They are often used to create utility classes that perform operations on data, but have no need to collect and store data.
It is necessary for an instance of the class to be created to execute the method.
What does the following statement do? Image puppy = new Image("file:c:\\images\terrier.jpg"); a) it creates an instance of the ImageView class with the terrier.jpg file passed to the constructor. b) It loads an image named "images\terrier.jpg" and stores the imagein the Image variable. c) It loads an image file named terrier.jpg which is found in the images folder on the user's C-drive. d) Nothing; it is not possible to include a path to a file when using the Image class.
It loads an image file named terrier.jpg which is found in the images folder on the user's C-drive.
In the following code, what will the call to super do? public class ClassB extends ClassA { public ClassB() { super(40); System.out.println("This is the last statement "+"in the constructor.");}} 1) This cannot be determined from the code. 2) It will call the method super and pass the value 40 to it as an argument. 3) It will call the constructor of ClassA that receives an integer as an argument. 4) The method super will have to be defined before we can say what will happen.
It will call the constructor of ClassA that receives an integer as an argument.
Look at the following code and determine what the call to super will do. public class ClassB extends ClassA { public ClassB() { super(10); } } 1) This cannot be determined form the code shown. 2) It will call the constructor of ClassA that receives an integer as an argument. 3) It will call the method named super and pass the value 10 to it as an argument. 4) The method super will have to be defined before we can say what will happen.
It will call the constructor of ClassA that receives an integer as an argument.
If a subclass constructor does not explicitly call a superclass constructor: 1) it must include the code necessary to initialize the superclass fields 2) the superclass fields will be set to the default values for their data types 3) Java will automatically call the superclass's default or no-arg constructor immediately after the code in the subclass's constructor executes 4) Java will automatically call the superclass's default or no-arg constructor just before the code in the subclass's constructor executes
Java will automatically call the superclass's default or no-arg constructor just before the code in the subclass's constructor executes
Look at the following code. Line 1public class ClassA Line 2{ Line 3public ClassA() {} Line 4public void method1(){} Line 5} Line 6public class ClassB extends ClassA Line 7{ Line 8public ClassB(){} Line 9public void method1(){} Line 10} Line 11public class ClassC extends ClassB Line 12{ Line 13public ClassC(){} Line 14public void method1(){} Line 15} Which method1 will be executed as a result of the following statements?ClassA item1 = new ClassC();item1.method1(); 1) Line 4 2) Line 9 3) Line 14 4) This is an error and will cause the program to crash.
Line 14
Assuming the following declaration exists:enum Tree { OAK, MAPLE, PINE }What will the following code display?System.out.println(Tree.OAK); 1) Tree.OAK 2) 0 3) 1 4) OAK 5) Nothing. This statement will cause an error.
OAK
If you have defined a class SavingsAccount with a public static method getNumberOfAccounts(), and created a SavingsAccount object referenced by the variable account20, which of the following will call the getNumberOfAccounts()method? 1) getNumberOfAccounts(); 2) SavingsAccount.getNumberOfAccounts(); 3) getNumberOfAccounts(account20); 4) None of the above, you cannot call a static method.
SavingsAccount.getNumberOfAccounts();
Java allows you to create objects of this class in the same way you would create primitive variables. - Random - String - PrintWriter - Scanner
String
Which of the following statements will create a reference, str, to the String, "Hello, World"? 1) String str = "Hello, World"; 2) string str = "Hello, World"; 3) String str = new "Hello, World"; 4) str = "Hello, World";
String str = "Hello, World";
To create a TextField control, you use the __________ class which is in the __________ package. a) TextField, javafx.text.control b) TextField, javafx.scene.control c) TextBox, javafx.scene.control d) TextField, javafx.textfield
TextField, javafx.scene.control
Assume the class BankAccount has been created, and the following statement correctly creates an instance of the class: BankAccount account = new BankAccount(5000.0); What is TRUE about the following statement?System.out.println(account); 1) The method will display unreadable binary data on the screen. 2) A compiler error will occur. 3) The account object's toString method will be implicitly called. 4) A runtime error will occur.
The account object's toString method will be implicitly called.
What will be returned from a method, if the following is the method header?public Rectangle getRectangle() 1) An object of the class Rectangle 2) The address of an object of the class Rectangle 3) The values stored in the data members of the Rectangle object the method changed 4) A graph of a rectangle
The address of an object of the class Rectangle
Given the following two-dimensional array declaration, which statement is TRUE? int [][] numbers = new int [6] [9]; A) The array numbers has 6 columns and 9 rows. B) The array numbers has 6 rows and 9 columns. C) The array numbers has 15 rows. D) The array numbers has 54 rows.
The array numbers has 6 rows and 9 columns.
What is wrong with the following code? public class ClassB extends ClassA { public ClassB() { int init = 10; super(40); } } 1) Nothing is wrong with the code. 2) The method super is not defined. 3) The call to the method super must be the first statement in the constructor. 4) No values may be passed to super.
The call to the method super must be the first statement in the constructor.
What will be the result of the following code? int num; string str = "555"; num = Integer.parseInt(string str) + 5; A) num will be set to 560. B) str will have a value of "560". C) The last line of code will cause an error. D) Neither num or str will be changed.
The last line of code will cause an error.
What is required for an interface method that has a body? 1) The method header must begin with the key word default. 2) A class that implements the interface must override the method. 3) The @Default annotation must precede the method header. 4) All of the above
The method header must begin with the key word default.
What is wrong with the following code? IntCalculator square = new IntCalculator() {public int calculate(int number){return number * number;} 1) The outer braces are not needed. 2) The inner braces are not needed. 3) The new key word is not needed. 4) The statement does not end with a semicolon.
The statement does not end with a semicolon.
In an inheritance relationship: 1) The superclass constructor always executes before the subclass constructor 2) The subclass constructor always executes before the superclass constructor 3) The constructor with the lowest overhead always executes first regardless of inheritance 4) The unified constructor always executes first regardless of inheritance
The superclass constructor always executes before the subclass constructor
Select all that apply. Given the statement shown below, which of the following statements are true? Scene scene = new Scene(hbox, 100, 500); a) The width of the scene will be 100 pixels. b) The height of the scene will be 100 pixels. c) A scene object named scene will be created. d) The root node is hbox.
The width of the scene will be 100 pixels, A scene object names scene will be created, the root node box is hbox.
Assuming three ImageView objects named puppy, kitten, and bunny have been created, what does the following statement do? HBox hbox = new HBox(5, puppy, kitten, bunny); a) The number 5 refers to the number of ImageView objects so there will be two empty spots for two more ImageView objects. b) There will be five pixels of space between the controls horizontally in the container. c) The controls will be displayed vertically with five pixels between them. d) the statement does nothing it contains an error.
There will be five pixels of space between the controls horizontally in the container.
If the following is from the method section of a UML diagram, which of the following statements is TRUE? + add(object2:Stock): Stock 1) This is a private method named add that accepts and returns objects of the Stock class. 2) This is a private method named Stock that adds two objects. 3) This is a public method named add that accepts and returns references to objects in the Stock class. 4) This is a public method named Stock that adds two objects.
This is a public method named add that accepts and returns references to objects in the Stock class.
What will be returned from the following method? public static int method() { double a = 8.5 + 9.5; return a; } A) 18.0 B) 18 (as an integer) C) D)
This is an error.
What will be returned from the following method? public static int methodA() { double a = 8.5 + 9.5; return a; } A) 18.0 B) 18 (as an integer) C) 8.0 D) This is an error.
This is an error.
Look at the following declaration:enum Tree { OAK, MAPLE, PINE }What is the fully-qualified name of the PINE enum constant? 1) PINE 2) enum.PINE 3) Tree.PINE 4) Tree(PINE) 5) PINE.Tree
Tree.PINE
True or False - A class in not an object, but a description of an object.
True
True or False - A class is not an object, but a description of an object.
True
True or False - A class's static methods do not operate on the fields that belong to any instance of the class.
True
True or False - A constructor is a method that is automatically called when an object is created.
True
True or False - A method that stores a value in a class's field or in some other way changes the value of a field is known as a mutator method.
True
True or False - A parameter variable's scope is the method in which the parameter is declared.
True
True or False - A sorting algorithm is a technique for scanning through an array and rearranging its contents in some specific order.
True
True or False - An ArrayList object automatically expands in size to accommodate the items stored in it.
True
True or False - An abstract class is not instantiated, but serves as a superclass for other classes.
True
True or False - An access specifier indicates how the class may be accessed.
True
True or False - An enumerated data type is actually a special type of class.
True
True or False - An event object is created when an event takes place.
True
True or False - An instance of a class does not have to exist in order for values to be stored in a class's static fields.
True
True or False - Any items typed on the command-line, separated by space, after the name of the class are considered to be one or more arguments that are to be passed into the main method.
True
True or False - Any method that calls a method with a throws clause in its header must either handle the potential exception or have the same throws clause.
True
True or False - Both instance fields and instance methods are associated with a specific instance of a class, and they cannot be used until an instance of the class is created.
True
True or False - Constants, variables, and the values of expressions may be passed as arguments to a method.
True
True or False - Declaring an array reference variable does not create an array.
True
True or False - Enum constants have a toString method.
True
True or False - Every class has a toString method and an equals method inherited from the Object class.
True
True or False - If a class has a method named finalize, it is called automatically just before an instance of the class is destroyed by the garbage collector.
True
True or False - If you write a toString method for a class, Java will automatically call the method any time you concatenate an object of the class with a string.
True
True or False - If you write a toString method to display the contents of an object, object1, for a class, Class1, then the following two statements are equivalent: System.out.println(object1); System.out.println(object1.toString());
True
True or False - Instance methods do not have the key word static in their headers.
True
True or False - Java does not limit the number of dimensions that an array may have.
True
True or False - Layout containers provide methods for fine-tuning the way controls are arranged.
True
True or False - No statement outside the method in which a parameter variable is declared can access the parameter by its name.
True
True or False - Objects in an array are accessed with subscripts, just like any other data type in an array.
True
True or False - Once an array is created, its size cannot be changed.
True
True or False - Shadowing is the term used to describe where the field name is hidden by the name of a local or parameter variable.
True
True or False - The Pos type must be imported from the javafx.geometry package.
True
True or False - The String[] args parameter in the main method header allows the program to receive arguments from the operating system command-line.
True
True or False - The VBox layout container arranges controls from top to bottom.
True
True or False - The expression in a return statement can be any expression that has a value.
True
True or False - The java.lang package is automatically imported into all Java programs.
True
True or False - The key word this is the name of a reference variable that an object can use to refer to itself.
True
True or False - The term "no-arg constructor" is applied to any constructor that does not accept arguments.
True
True or False - To compare the contents of two arrays, you must compare the elements of the two arrays.
True
True or False - Two general categories of methods are void methods and value returning methods.
True
True or False - When a subclass extends a superclass, the public members of the superclass become public members of the subclass.
True
True or False - When an array of objects is declared, but not initialized, the array values are set to null.
True
True or False - When an object is passed as an argument, it is actually a reference to the object that is passed.
True
True or False - When an object reference is passed to a method, the method may change the value in the object.
True
True or False - You must have a return statement in a value-returning method.
True
True or False - an object can store data.
True
What would be the results of the following code? int[] array1 = new int[25]; .......... - Value contains the highest value in array1. - Value contains the lowest value in array1. - Value contains the sum of all the values in array1. - Value contains the average of the values in array1.
Value contains the lowest value in array1.
In UML diagrams, inheritance is shown: 1) With a line that has an open arrowhead at one end that points to the superclass 2) With a line that has an open arrowhead at one end that points to the subclass 3) With a line that has a closed arrowhead at one end that points to the superclass 4) With a line that has a closed arrowhead at one end that points to the subclass
With a line that has an open arrowhead at one end that points to the superclass
What would be the results of the following code? int [] x = { 55, 33, 88, 22, 99, 11, 44, 66, 77 }; int a = 10; if (x[2] > x[5]) a = 5; else a = 8; A) a = 5 B) a = 8 C) a = 10 D) This is a compilation error, you cannot compare array elements.
a = 5
When a method tests an argument and returns a true or false value, it should return: - a zero for true and a one for false - a boolean value - a zero for false and a non-zero for true - a method should not be used for this type test
a boolean value
If ClassC extends ClassB, which extends ClassA, this would be an example of: 1) multiple inheritance 2) a chain of inheritance 3) a family tree 4) packaging
a chain of inheritance
In a general sense, a method is: - a plan - a statement inside a loop - a comment - a collection of statements that performs a specific task
a collection of statements that performs a specific task
If you attempt to use a local variable before it has been given a value: - a compiler error will occur - the local variable will always contain the value 0 - the results will be unpredictable - the local variable will be ignored
a compiler error will occur
If the this variable is used to call a constructor: 1) a compiler error will result, if it is not the first statement of the constructor 2) a compiler error will result, if it is the first statement of the constructor 3) nothing will happen 4) the this variable cannot be used as a constructor call
a compiler error will result, if it is not the first statement of the constructor
The whole-part relationship created by object aggregation is more often called: 1) a has a relationship 2) an inner class relationship 3) an extra class relationship 4) an inside class relationship
a has a relationship
What is stored by a reference variable? - A binary encoded decimal - A memory address - An object - A string
a memory address
A ragged array is: - a two-dimensional array for which the number of rows is unknown - a one-dimensional array for which the number of elements is unknown - a two-dimensional array where the rows are of different lengths - There is no such thing as a ragged array
a two-dimensional array where the rows are of different lengths
In the following code, Integer.parseInt(str), is an example of: int num; string str = "555"; num = Integer.parseInt(str) + 5; A) a value-returning method B) a void method C) a local variable D) a complex method
a value-returning method
In the following code, System.out.println(num) is an example of: double num = 5.4; System.out.println(num); num = 0.0; A) a value-returning method B) a void method C) a complex method D) a local variable
a void method
Look at the following statement. import java.util.*; This is an example of: 1) a wildcard import 2) an explicit import 3) unconditional import 4) conditional import
a wildcard import
When an object, such as a String, is passed as an argument, it is: A) actually a reference to the object that is passed B) passed by value like any other parameter value C) encrypted D) necessary to know exactly how long the string is when writing the program
actually a reference to the object that is passed
You can use this ArrayList class method to insert an item at a specific location in an ArrayList. A) insert B) add C) store D) putItem
add
Breaking a program down into small manageable methods: A) makes problems more easily solved B) allows for code reuse C) simplifies programs D) all of these
all of these
Local variables: - are hidden from other methods - may have the same name as local variables in other methods - lose the values stored in them between calls to the method in which the variable is declared - All of these
all of these
What does the following statement do? double[] array1 = new double[10]; - Declares array1 to be a reference to an array of double values - Creates an instance of an array of 10 double values - Will allow valid subscripts in the range of 0 - 9 - All of these
all of these
Which of the following is NOT a benefit derived from using methods in programming? - Pproblems are more easily solved. - simplifies programs - code reuse - All of these are benefits.
all of these are benefits
When an "is a" relationship exists between objects, it means that the specialized object has: 1) some of the characteristics of the general class, but not all, plus additional characteristics 2) some of the characteristics of the general object, but not all 3) none of the characteristics of the general object 4) all the characteristics of the general object, plus additional characteristics
all the characteristics of the general object, plus additional characteristics
What will be returned from the following method? public static float[] getValue(int x) - a float value - an array of float values - an integer - an array of integers
an array of float values
Select all that apply. It may be possible to simplify event handler code by using which of the following? a) nested classes b) anonymous inner classes c) lambda expressions d) listener expressions
anonymous inner classes, lambda expressions
Local variables can be initialized with: - constants - parameter values - the results of an arithmetic operation - Any of these
any of these
A value-returning method must specify this as its return type in the method header. - an int - a double - a boolean - any valid data type
any valid data type
All @param tags in a method's documentation comment must: - end with a */ - appear after the general description of the method - appear before the method header - span several lines
appear after the general description of the method
All fields declared in an interface: 1) are final and static 2) have protected access 3) must be initialized in the class implementing the interface 4) have private access
are final and static
Values stored in local variables: A) Are lost between calls to the method in which they are declared B) retain their values from the last call to the method in which they are declared C) may be referenced by the calling method D) may be referenced by any other method, if the method in which they are declared is a public method
are lost between calls to the method in which they are declared
Values that are sent into a method are called: A) variables B) arguments C) literals D) types
arguments
Java performs ________, which means that it does not allow a statement to use a subscript that is outside the range of valid subscripts for the array. - active array sequencing - array bounds checking - scope resolution binding - buffer overrun protection
array bounds checking
A class's responsibilities include: 1) the things a class is responsible for doing 2) the things a class is responsible for knowing 3) both A and B 4) neither A nor B
both A and B
When a subclass overloads a superclass method: 1) Both methods may be called with a subclass object 2) Only the subclass method may be called with a subclass object 3) Only the superclass method may be called with a subclass object 4) Neither method may be called with a subclass object
both methods may be called with a subclass object
After the header, the body of the method appears inside a set of: 1) brackets, [] 2) parentheses, () 3) braces, {} 4) double quotes, ""
braces, {}
Methods are commonly used to: - speed up the compilation of a program - break a problem down into small manageable pieces - emphasize certain parts of the logic - document the program
break a problem down into small manageable pieces
One or more objects may be created from a(n): A) field B) class C) method D) instance
class
In your textbook the general layout of a UML diagram is a box that is divided into three sections. The top section has the ________; the middle section holds ________; the bottom section holds ________. 1) class name; attributes or fields; methods 2) class name; object name; methods 3) object name; attributes or fields; methods 4) object name; methods; attributes or fields
class name; attributes or fields; methods
In the cookie cutter metaphor, think of the ________ as a cookie cutter and ________ as the cookies. 1) object; classes 2) class; objects 3) class; fields 4) attribute; methods
class; objects
In memory, an array of String objects: - consists of elements, each of which is a reference to a String object - is always implemented as a ragged array - consists of elements, each of which is a String object - must be initialized when the array is declared
consists of elements, each of which is a reference to a String object
When an argument value is passed to a method, the receiving parameter variable is: A) B) C) D)
declared in the method header inside the parentheses
To create a method you must write its: A) header B) return type C) body D) definition
definition
In a @return tag statement the description: A) cannot be longer than one line B) describes the return value C) must be longer than one line D) describes the parameter values
describes the return value
Given the following method header, which of the method calls would be an error? public void displayValues(int x, int y) - displayValue(a,b); // where a is a short and b is a byte - displayValue(a,b); // where a is an int and b is a byte - displayValue(a,b); // where a is a short and b is a long - They would all give an error.
displayValue(a,b); // where a is a short and b is a long
Given the following method header, which of the method calls would be an error? public void displayValues(int x, int y) A) displayValue(a,b); // where a is a short and b is a byte B) displayValue(a,b); // where a is an int and b is a byte C) displayValue(a,b); // where a is a short and b is a long D) They would all give an error.
displayValue(a,b); // where a is a short and b is a long
Given the following method header, which of the method calls would be an error?public void displayValues(double x, int y) - displayValue(a,b); // where a is a long and b is a byte - displayValue(a,b); // where a is an int and b is a byte - displayValue(a,b); // where a is a short and b is a long - They would all give an error.
displayValue(a,b); // where a is a short and b is a long
Given the following method header, which of the method calls would be an error?public void displayValues(double x, int y) A) displayValue(a,b); // where a is a long and b is a byte B) displayValue(a,b); // where a is an int and b is a byte C) displayValue(a,b); // where a is a short and b is a long D) They would all give an error.
displayValue(a,b); // where a is a short and b is a long
The process of breaking a problem down into smaller pieces is sometimes called: A) divide and conquer B) scientific method C) top-down programming D) whole-into-part
divide and conquer
This is a variable whose value is never changed, but it isn't declared with the final key word. 1) virtually constant variable 2) effectively final variable 3) default variable 4) anonymous inner variable
effectively final variable
An anonymous inner class must: 1) implement an interface 2) extend another class 3) either A or B 4) both A and B
either A or B
A(n) ___________ is an action that takes place in an application, such as the clicking of a button. a) instance b) effect c) case d) event
event
An action that takes place while a program is running is a(n) __________. a) event source b) event handler c) event d) event object
event
Programs that operate in a GUI environment must be: a) event driven b) in color c) dialog boxes d) layout managers
event driven
It is common practice in object-oriented programming to make all of a class's: 1) methods private 2) fields private 3) fields public 4) fields and methods public
fields private
A class specifies the ________ and ________ that a particular type of object has. 1) relationships; methods 2) fields; object names 3) fields; methods 4) relationships; object names
fields; methods
When an event takes place, the control responsible for the event creates an event ________. - source - object - handler - firing
firing
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());
If numbers is a two-dimensional int array that has been initialized and total is an int that has been set to 0, which of the following will sum all the elements in the array?
for (int row = 0; row < numbers.length; row++) { for (int col = 0; col < numbers[row].length; col++) total += numbers[row][col] }
To receive text that a user has typed into a TextField control, you call this ___________ method. a) inputText b) getInput c) getText d) getInputText
getText
Which of the following statements correctly adds a label to the first row and second column of a GridPane object? a) gridpane.add(myLabel, 1, 2); b) gridpane.add(myLabel, 2, 1); c) gridpane.add(myLabel, 0, 1); d) gridpane.add(myLabel, 1, 0);
gridpane.add(myLabel, 0, 1);
Any method that calls a method with a throws clause in its header must:
handle the potential exception; have the same throws clause
A constructor:
has the same name as the class
A constructor: 1) always accepts two arguments 2) has return type of void 3) has the same name as the class 4) always has an access specifier of private
has the same name as the class
Overloading means multiple methods in the same class: 1) have the same name, but different return types 2) have different names, but the same parameter list 3) have the same name, but different parameter lists 4) perform the same function
have the same name, but different parameter lists
Quite often you have to use this statement to make a group of classes available to a program. 1) import 2) use 3) link 4) assume
import
Which of the following import statements is required in order to write an event handler class? a) import javafx.event.EventHandler; b) import javafx.event.ActionEvent; c) import javafx.EventHandler; d) import javafx.EventHandler.event;
import javafx.event.EventHandler;
Which of the following import statements is required in order to create a BorderPane layout container? a) import javafx.scene.layout.Box; b) import javafx.scene.layout; c) import javafx.layout.scene.BorderPane; d) import javafx.scene.layout.BorderPane;
import javafx.scene.layout.BorderPane;
One important differences between the command line interface and a GUI interface is that __________. a) in command line the background color of the monitor will always be black but in a GUI it can be any color b) in a GUI environment the user determines the order in which things happen while the user has no control over the order or events in a command line interface c) users must type information in a command line interface but, when using a GUI typing is never required d) All of these are important differences
in a GUI environment the user determines the order in which things happen while the user has no control over the order or events in a command line interface
You should not define a class field that is dependent upon the values of other class fields: 1) in order to avoid having stale data 2) because it is redundant 3) because it should be defined in another class 4) in order to keep it current
in order to avoid having stale data
To display an image in a JavaFX application you must ______________. a) include either the Image or the ImageView class b) include both the setImage and the ViewImage classes c) include both the Image and the ImageView classes d) include either the setImage or the ViewImage class
include both the Image and the ImageView classes
In Java, you do not use the new operator when you use a(n): - array size declarator - initialization list - two-dimensional array - All of these
initialization list
When an object is created, the attributes associated with the object are called: - instance fields - instance methods - fixed attributes - class instances
instance fields
Methods that operate on an object's fields are called: 1) instance variables 2) instance methods 3) public methods 4) private methods
instance methods
Assume that the following method header is for a method in class A. public void displayValue(int value) Assume that the following code segments appear in another method, also in class A. Which contains a legal call to the displayValue method? - int x = 7;void displayValue(x); - int x = 7;displayValue(x); - int x = 7;displayValue(int x); - int x = 7;displayValue(x)
int x = 7;displayValue(x);
Which of the following is a valid declaration for a ragged array? - int[] ragged = new int[5]; - int[][] ragged = new int[5][6]; - int[][] ragged = new int[5][]; - int[][] ragged = new int[][5];
int[][] ragged = new int[5][];
A search algorithm: - is a way to locate a specific item in a larger collection of data - is rarely used with arrays - arranges elements in ascending order - arranges elements in descending order
is a way to locate a specific item in a larger collection of data
A deep copy of an object: 1) is an assignment of that object to another object 2) is an operation that copies an aggregate object, and all the objects it references 3) is a bogus term, it has no meaning 4) is always a private method
is an operation that copies an aggregate object, and all the objects it references
When the this variable is used to call a constructor: 1) it must be the first statement in the constructor making the call 2) it must be the last statement in the constructor making the call 3) it can be anywhere in the constructor making the call 4) you cannot use the this variable in a constructor call
it must be the first statement in the constructor making the call
When an argument is passed to a method: A) its value is copied into the method's parameter variable B) its value may be changed within the called method C) values may not be passed to methods D) the method must not assign another value to the parameter that receives the argument
its value is copied into the method's parameter variable
The following package is automatically imported into all Java programs. 1) java.java 2) java.default 3) java.util 4) java.lang
java.lang
The ArrayList class is in this package. - java.arraylist - java.lang - java.array - java.util
java.util
This is a special type of expression used to create an object that implements a functional interface. 1) lambda 2) beta 3) alpha 4) sigma
lambda
Each array in Java has a public field names _________ that contains the number of elements in the array. - size - capacity - length - limit
length
To return an array of long values from a method, use this as the return type for the method. A) long B) long[] C) long[ARRAY_SIZE] D) []long
long[]
This part of a method is a collection of statements that are performed when the method is executed. A) method header B) return type C) method body D) method modifier
method body
Replacing inadequate superclass methods with more suitable subclass methods is known as what? 1) Method upgrading 2) Tactical inheritance 3) Method overriding 4) Method overloading
method overriding
Class objects normally have ________ that perform useful operations on their data, but primitive variables do not. - fields - instances - methods - relationships
methods
Class objects normally have ________ that perform useful operations on their data, but primitive variables do not. 1) fields 2) instances 3) methods 4) relationships
methods
The super statement that calls the superclass constructor: 1) must be the first statement in the superclass's constructor 2) can appear in any method of the subclass 3) must be the first statement in the subclass's constructor 4) is deprecated and is no longer supported in newer versions of Java
must be the first statement in the subclass's constructor
For this question, assume myView references an ImageView object. In order to preserve the image's aspect ratio (so it does not appear stretched or distorted), you should use which of the following? A) myView.setPreserveRatio(false); B) C) D)
myView.setPreserveRatio(true);
In order to leave 15 pixels of space in an HBox container, use which of the following statements? a) myhbox = setPadding(15); b) myhbox.setPadding(15); c) myhbox.setPadding.Insets(15); d) myhbox.setPadding(new Insets(15));
myhbox.setPadding(new Insets(15));
Which of the following values can be passed to a method that has an int parameter variable? - float - double - long - All of these - None of these
none of these
What is wrong with the following code? public class ClassB extends ClassA { public ClassB() { super(40); System.out.println("This is the last statement " +"in the constructor."); } } - Nothing is wrong with this code - the method super is not defined - the call to the method super must be the first statement in the constructor - no values may be passed to super.
nothing is wrong with this code
You use this method to determine the number of items stored in an ArrayList object. A) numberItems B) capacity C) size D) items
numberItems
If numbers is a two-dimensional array, which of the following would give the length of row r? - numbers.length - numbers.length[r] - numbers[r].length[r] - numbers[r].length
numbers[r].length
A UML diagram does not contain: A) the class name B) the method names C) the field names D) object names
object names
Most programming languages that are in use today are: 1) procedural 2) logic 3) object-oriented 4) functional
object-oriented
You cannot use the == operator to compare the contents of: 1) objects 2) strings 3) integers 4) Boolean values
objects
if you set a scene's size to a width and height that is smaller than the width and height of the image to be displayed __________. a) only part of the image will be displayed b) the image will only occupy part of the window c) the scene will automatically be resized to fit the image d) the image will automatically be resized to fit the window
only part of the image will be displayed
A subclass can directly access: 1) all members of the superclass 2) only public and private members of the superclass 3) only protected and private members of the superclass 4) only public and protected members of the superclass
only public and protected members of the superclass
The lifetime of a method's local variable is: - the duration of the program - the duration of the class to which the method belongs - the duration of the method that called the local variable's method - only while the method is executing
only when the method is executing
Enumerated types have this method, which returns the position of an enum constant in the declaration list. 1) toString 2) position 3) ordinal 4) location
ordinal
If you do not provide an access specifier for a class member, the class member is given ________ by default. 1) private 2) public 3) protected 4) package
package
This is a group of related classes. 1) archive 2) package 3) collection 4) attachment
package
A special variable that holds a value being passed into a method is called what? - Modifier - Parameter - Alias - Argument
parameter
In the header, the method name is always followed by this: A) parentheses B) return type C) data type D) braces
parentheses
Which of the following is included in a method call? A) return type B) method modifiers C) parentheses D) return variable
parentheses
A constructor is a method that: - returns an object of the class - never receives any arguments - with the name ClassName.constructor. - performs initialization or setup operations.
performs initialization or setup operations
A subclass may call an overridden superclass method by: 1) prefixing its name with the super key word and a dot (.) 2) prefixing its name with the name of the superclass in parentheses 3) using the extends keyword before the method is called 4) calling the superclass method first and then calling the subclass method
prefixing its name with the super key word and a dot (.)
When you are working with a ________, you are using a storage location that holds a piece of data. 1) primitive variable 2) reference variable 3) numeric literal 4) binary number
primitive value
When you are working with a ________, you are using a storage location that holds a piece of data. A) primitive variable B) reference variable C) numeric literal D) binary number
primitive variable
In an interface all methods have: 1) private access 2) protected access 3) public access 4) packaged access
public access
Which of the following statements declares Salaried as a subclass of PayType? 1) public class Salaried extends PayType 2) public class Salaried implements PayType 3) public class Salaried derivedFrom(Paytype) 4) public class PayType derives Salaried
public class Salaried extends PayType
If ClassA extends ClassB, then: 1) public and private members of ClassB are public and private, respectively, in ClassA 2) public members in ClassB are public in ClassA, but private members in ClassB cannot be directly accessed in ClassA 3) neither public or private members in ClassB can be directly accessed in ClassA 4) private members in ClassB are changed to protected members in ClassA
public members in ClassB are public in ClassA, but private members in ClassB cannot be directly accessed in ClassA
Which of the following is a correct method header for receiving a two-dimensional array as an argument? - public static void passArray(int[1,2]) - public static void passArray(int [][]) - public static void passArray(int[1],[2]) - public static void passArray(int[], int[])
public static void passArray(int [][])
The process of connecting an event handler object to a control is called ___________ the event handler. a) passing b) registering c) applying d) rendering
registering
This ArrayList class method deletes an item from an ArrayList. - remove - delete - erase - purge
remove
Which of the following is not part of a method call? - method name - return type - parentheses - all of these
return type
Which of the following is NOT a part of the method header? - return type - method name - parentheses - semicolon
semicolon
You can use this ArrayList class method to replace an item at a specific location in an ArrayList. - replace - add - store - set
set
What method do you call to register an event handler with a Button control? a) setAction b) onClickAction c) setOnClick d) setOnAction
setOnAction
To add padding to an HBox you can call the ___________ method. a) HBoxPadding b) SetHBoxPadding c) setPadding d) setHBoxPad
setPadding
The Application class's __________ method is the main entry point for a JavaFX application. a) start b) init c) addWindow d) mainFX
start
An object's _______ is simply the data that is stored in the object's fields at any given moment. - value - assessment - record - state
state
Instance methods do not have this key word in their headers: - public - static - private - protected
static
Static methods can only operate on ________ fields. 1) instance 2) static 3) global 4) local
static
Given that String[] str has been initialized, to get a copy of str[0] with all characters converted to upper case, use the following statement: A) str.uppercase(); B) str[0].upperCase(); C) str.toUpperCase(); D) str[0].toUpperCase();
str[0].toUpperCase();
What do you call the number that is used as an index to pinpoint a specific element within an array? - subscript - global unique identifier - element - argument
subscript
What key word can you use to call a superclass constructor explicitly? 1) goto 2) this 3) super 4) extends
super
In order to do a binary search on an array: A) the values of the array must be numeric B) the array must first be sorted in ascending order C) you must first do a sequential search of the array to assure the element you are looking for is there D) there are no requirements
the array must first be sorted in ascending order
This indicates the number of elements, or values, the array can hold. - the new operator - the array's size declarator - the array's data type - the version of Java
the array's size declarator
The header of a value-returning method must specify this. - The method's local variable names - The name of the variable in the calling program that will receive the returned value - The data type of the return value - All of these
the data type of the return value
The scope of a public instance field is: 1) only the class in which it is defined 2) inside the class, but not inside any method 3) inside the parentheses of a method header 4) the instance methods and methods outside the class
the instance methods and methods outside the class
The scope of a private instance field is: - the instance methods of the same class - inside the class, but not inside any method - inside the parentheses of a method header - the method in which they are defined
the instance methods of the same class
The scope of a private instance field is: 1) the instance methods of the same class 2) inside the class, but not inside any method 3) inside the parentheses of a method header 4) the method in which they are defined
the instance methods of the same class
A static field is created by placing: 1) the key word static after the field name 2) the key word static after the access specifier and before the field's data type 3) the key word static after the access specifier and field's data type 4) it in a static field block
the key word static after the access specifier and before the field's data type
When an individual element of an array is passed to a method: - a reference to the array is passed - it is passed like any other variable - the method does not have direct access to the original array - All of these
the method does not have direct access to the original array
A parameter variable's scope is: - the method in which the parameter is declared - the class to which the method belongs - the main method - All of these
the method in which the parameter is declared
A parameter variable's scope is: A) the method in which the parameter is declared B) the class to which the method belongs C) the main method D) all of these
the method in which the parameter is declared
When an object is passed as an argument to a method, what is passed into the method's parameter variable? 1) the class name 2) the object's memory address 3) the values for each field 4) the method names
the object's memory address
When you pass an argument to a method, be sure that the argument's data type is compatible with: - the parameter variable's data type - the method's return type - the version of Java currently being used - IEEE standards
the parameter's variable's data type
The phrase divide and conquer is sometimes used to describe: A) the backbone of the scientific method B) the process of dividing functions C) the process of breaking a problem down into smaller pieces D) the process of using division to solve a mathematical problem
the process of breaking a problem down into smaller pieces
If you attempt to perform an operation with a null reference variable: 1) the resulting operation will always be zero 2) the results will be unpredictable 3) the program will terminate 4) Java will create an object to reference the variable
the program will terminate
If a BorderPane region does not contain anything __________. a) the region will appear gray by default b) the region will not appear in the GUI c) an error will occur d) content from an adjacent region will be duplicated to appear in the empty region
the region will not appear in the GUI
In a UML diagram to indicate the data type of a variable enter: 1) the variable name followed by the data type 2) the variable name followed by a colon and the data type 3) the class name followed by the variable name followed by the data type 4) the data type followed by the variable name
the variable name followed by a colon and the data type
The only limitation that static methods have is: 1) they can refer to only non-static members of the class 2) they can only be called from static members of the class 3) they must be declared as public methods 4) they cannot refer to non-static members of the class
they cannot refer to non-static members of the class
Two or more methods in a class may have the same name as long as: - they have different return types - they have different parameter lists - they have different return types, but the same parameter list - you cannot have two methods with the same name
they have different parameter lists
What does the following UML diagram entry mean? + setHeight(h : double) : void - this is a public attribute named Height and is a double data type - this is a private method with no parameters and returns a double data type - this is a private attribute named Height and is a double data type - this is a public method with a parameter of data type double and does not return a value
this is a public method with a parameter of data type double and does not return a value
Select all that apply. Which of the following are regions where content can be displayed in the BorderPane layout container? a) top and bottom b) center c) above and below center d) left and right
top and bottom, center, left and right
The sequential search algorithm: - requires the array to be ordered - must always be implemented as a method - uses a loop to sequentially step through an array, starting with the first element - will not execute, if the element is not in the array
uses a loop to sequentially step through an array, starting with the first element
Data hiding, which means that critical data stored inside the object is protected from code outside the object, is accomplished in Java by: 1) using the public access specifier on the class methods 2) using the private access specifier on the class methods 3) using the private access specifier on the class definition 4) using the private access specifier on the class fields
using the private access specifier on the class fields
Data hiding, which means that critical data stored inside the object is protected from code outside the object, is accomplished in Java by: A) using the public access specifier on the class methods B) using the private access specifier on the class methods C) using the private access specifier on the class definition D) using the private access specifier on the class fields
using the private access specifier on the class fields
What would be the results of the following code? final int SIZE = 25; .......... for (int a = 0; a < array1.length; a++) { value += array1{a}; } - Value contains the highest value in array1. - Value contains the lowest value in array1. - Value contains the sum of all the values in array1. - This would cause the program to crash.
value contains the sum of all the values in array1.
This type of method performs a task and sends a value back to the code that called it. A) value-returning B) void C) complex D) local
value-returning
This type of method performs a task and then terminates. - value-returning - void - local - simple
void
The binary search algorithm: - is less efficient than the sequential search algorithm - will cut the portion of the array being searched in half each time the loop fails to locate the search value - will have a maximum number of comparisons equal to the number of elements in the array - will have an average of N/2 comparisons, where N is the number of elements in the array
will cut the portion of the array being searched in half each time the loop fails to locate the search value
To compare two objects in a class: 1) use the == operator, e.g. object1 == object2 2) write a method to do a byte-by-byte compare of the two objects 3) write an equals method that will make a field by field compare of the two objects 4) Since objects consist of several fields, you cannot compare them
write an equals method that will make a field by field compare of the two objects
Which of the following is NOT involved in finding the classes when developing an object-oriented application? 1) Describe the problem domain. 2) Identify all the nouns. 3) Write the code. 4) Refine the list of nouns to include only those that are relevant to the problem.
write the code
What would be the results after the following code was executed? int[] x = {23, 55, 83, 19}; int[] y = {36, 78, 12, 24}; for (int a = 0; a < x.length; a++) { x[a] =y[a]; y[a] = x[a]; } - x[] = {36, 78, 12, 24} and y[] = {23, 55, 83, 19} - x[] = {36, 78, 12, 24} and y[] = {36, 78, 12, 24} - x[] = {23, 55, 83, 19} and y[] = {23, 55, 83, 19} - This is a compilation error.
x[] = {36, 78, 12, 24} and y[] = {36, 78, 12, 24}
What would be the results after the following code was executed? int[] x = {23, 55, 83, 19}; int[] y = {36, 78, 12, 24}; x = y; y = x; A) x[] = {36, 78, 12, 24} and y[] = {23, 55, 83, 19} B) x[] = {36, 78, 12, 24} and y[] = {36, 78, 12, 24} C) x[] = {23, 55, 83, 19} and y[] = {23, 55, 83, 19} D) This is a compilation error.
x[] = {36, 78, 12, 24} and y[] = {36, 78, 12, 24}
For the following code, which statement is NOT true? public class Circle { private double radius; public double x; private double y; } 1) x is available to code that is written outside the Circle class. 2) radius is not available to code written outside the Circle class. 3) radius, x, and y are called members of the Circle class. 4) y is available to code that is written outside the Circle class.
y is available to code that is written outside the Circle class.
For the following code, which statement is not true? public class Sphere { private double radius; public double x; private double y; private double z; } - x is available to code that is written outside the Circle class. - radius is not available to code written outside the Circle class. - radius, x, y, and z are called members of the Circle class. - z is available to code that is written outside the Circle class.
z is available to code that is written outside the Circle class.
