Deck 4: More Object Concepts

Question 1

A disadvantage of Java is the large memory requirements to store a separate copy of each variable and method for each instantiation of a class.

Answer 1

False

Question 2

When you multiply an int and a double , the result is the int .

Answer 2

False

Question 3

You can overload methods correctly by providing different parameter lists for methods with the same name.

Answer 3

True

Question 4

When you properly ____ a method, you can call it providing different argument lists, and the appropriate version of the method executes.

A) declare
B) overload
C) name
D) delete

Question 5

When you overload a Java method, you write multiple methods with a shared name.

Question 6

When they have the same name, variables within ____ of a class override the class's fields.

A) packages
B) statements
C) fields
D) methods

Question 7

A locally declared variable always ____ another variable with the same name elsewhere in the class.

A) creates
B) masks
C) deletes
D) uses

Question 8

An alternative to importing a class is to import an entire package of classes.

Question 9

A block can exist entirely within another block or entirely outside and separate from another block, and sometimes blocks can overlap.

Question 10

If you give the same name to a class's instance field and to a local method variable, the instance variable overrides the method's local variable.

Question 11

Within any class or method, the code between a pair of curly braces is called a(n) ____.

A) overload
B) argument
C) scope
D) block

Question 12

When you write your own constructors, you cannot write versions that receive parameters.

Question 13

A method can receive ____ arguments, even if it is defined as needing double arguments.

A) string
B) integer
C) constructor
D) send

Question 14

____ involves using one term to indicate diverse meanings, or writing multiple methods with the same name but with different parameter lists.

A) Referencing
B) Overloading
C) Nesting
D) Signing

Question 15

When an application contains just one version of a method, you can call the method using a(n) ____ of the correct data type.

A) parameter
B) scope
C) output
D) constructor

Question 16

Object-oriented programmers use the term ____ when a child class contains a field or method that has the same name as one in the parent class.

A) out of scope
B) ambiguous
C) override
D) parent friendly

Question 17

It is a convenience to be able to use one reasonable name for ____ that are functionally identical except for argument types.

A) arguments
B) classes
C) tasks
D) packages

Question 18

It is illegal to declare the same variable name more than once within a block.

Question 19

Fields declared to be static are not always final .

Question 20

A variable comes into existence, or ____, when you declare it.

A) goes out of scope
B) comes into scope
C) overrides scope
D) is referenced

Question 21

The ____ package contains is implicitly imported into Java programs and is the only automatically imported, named package.

A) javax.swing
B) java.lang
C) JOptionPane
D) System

Question 22

The reference to an object that is passed to any object's nonstatic class method is called the ____.

A) magic number
B) this reference
C) literal constant
D) reference

Question 23

If a class's only constructor requires an argument, you must provide an argument for every ____ of the class that you create.

A) parameter
B) type
C) object
D) method

Question 24

The ____ statement notifies the program that you will be using the data and method names that are part of the imported class or package.

A) use
B) package
C) class
D) import

Question 25

When you instantiate an object from a class, ____ is reserved for each instance field in the class.

A) a constructor
B) a signature
C) memory
D) a field name

Question 26

In a Java ____________________ statement, you use a wildcard symbol to represent all the classes in a package.

Question 27

When an object of one class is a data field within another class, they are related by ____.

A) extension
B) scope
C) composition
D) is-a

Question 28

The compiler determines which version of a method to call by the method's ____.

A) name
B) signature
C) output
D) constructor

Question 29

When you ____________________ methods, you risk creating an ambiguous situation-one in which the compiler cannot determine which method to use.

Question 30

You can use the asterisk (*) as a ____, which indicates that it can be replaced by any set of characters.

A) magic number
B) wildcard symbol
C) character symbol
D) placeholder

Question 31

A(n) ____________________ begins immediately after the method declaration and ends at the end of the method.

Question 32

You can use ____ arguments to initialize field values, but you can also use arguments for any other purpose.

A) object
B) constructor
C) data
D) field

Question 33

Due to automatic type promotion, when a method with a double parameter is passed an integer, the integer will be promoted to a(n) ____.

A) integer
B) short
C) boolean
D) double

Question 34

Another name for a nonstatic member class is a(n) ____.

A) static member class
B) inner class
C) local class
D) anonymous class

Question 35

When calling this() from a constructor, it must be the ____ statement within the constructor.

A) first
B) ending
C) second
D) indented

Question 36

____ variables are variables that are shared by every instantiation of a class.

A) Integer
B) Instance
C) Class
D) Time

Question 37

When you pass a(n) ____________________, you pass a memory address.

Question 38

It is not necessary to create an instance of the Math class because the constants and methods of the class are ____.

A) void
B) final
C) static
D) public

Question 39

A(n) ____________________ is simply a folder that provides a convenient grouping for classes.

Question 40

If you want all objects to share a single nonchanging value, then the field is static and ______.

A) end
B) final
C) permanent
D) class

Question 42

List the three things you can do that allow you to use prewritten classes.

Question 43

 Using Java statements, show how you can use the LocalDate class by using the full path and by using an import statement.

Question 44

int aMethod(int x)
void aMethod(int x)
In the above statements, explain why these two methods are illegal in the class.

Question 45

Explain why it is a problem that the highlighted statements are local variables. How could you fix this problem?

Question 46

In the above code, what happens to the value of aNumber when the main() method is executed? What happens to the value of aNumber when the firstMethod and secondMethod methods are executed?

Question 47

Explain the java.lang package and why it is important. 

Question 48

Write Java statements that use the now() and of() methods in the LocalDate class.

Question 49

What is overloading a method? What conditions must be satisfied in the parameter lists of an overloaded method?

Question 50

What is the difference between class variables and instance variables?

Question 51

List and describe the four types of nested classes.

Question 52

The Student class above will allow Student information to be constructed in various ways, but is repetitive. How could you use the this reference to reduce the amount of repetitious code and make it less error-prone?

Question 53

Describe the impact that blocks and methods have on variables with the same name.

Question 54

What does a programmer need to know in order to use two variables with the same name in a class?

Question 55

Explain why the highlighted statements will result in an illegal action.

Question 56

Describe how a Java variable comes into and out of scope.

Question 57

What does it mean when a variable overrides another variable? 

Question 58

What is automatic type promotion in method calls? Give an example of how this works.

Question 59

Describe a block and define an outer block and an inner block.

Question 60

What is a reference and what is the meaning of the keyword this ?

Question 61

In the above code, if the simpleMethod() method received a double or integer value, the resulting output is "Method receives double parameter". Explain how Java can promote one data type to another when a parameter is passed to a method.

Question 62

What is the phenomenon called shadowing?

Question 63

Explain and describe the this reference. How is the this reference used in each of the above methods?

Question 64

public class StudentScores
{
   private int ScoreOne;
   private int ScoreTwo;
   private int ScoreThree;
____
____
____
____
____
}
Using the code above, fill in the blank lines provided to create a constructor that will require parameters for the three score data fields. Be sure to include the necessary brackets and semicolons.

Question 65

public class StudentScores
{
   private int ScoreOne;
   private int ScoreTwo;
   private int ScoreThree;
____
____
____
____
____
}
Suppose you want to assign all students a score of 95 on the third test. Using the code above, fill in the blank lines provided to create a two-parameter constructor that will require parameters for the first and second test score data fields, and will assign a value of 95 to the third test score data field. Be sure to include the necessary brackets and semicolons.

Question 66

In the above code, what would happen if calculateInterest was passed the values of 100 for the bal and .10 for the interest rate? What would happen if calculateInterest was passed the values of 100 for the bal and 10 for the interest rate? Why is it a problem when these values are passed to the calculateInterest method, and what would be a possible solution to fix the problem?