Saddleback CS 4A Java Final Chapter 9 – Flashcards

A constructor can access ________. 1. a local variable defined in any method 2. a private instance variable 3. a public instance variable 4. a static variable

A method that is associated with an individual object is called ________. 1. a static method 2. a class method 3. an instance method 4. an object method

T/F A static data field can be accessed from any method in the same class.

T/F A static method in a class can access the class variables in the same class.

T/F A static method in a class can access the instance variables in the same class

T/F All data fields in an object have default values.

An immutable class cannot have ________. 1. public data fields 2. private data fields 3. public constructors 4. no-arg constructors 5. static data fields

An object is an instance of a ________. 1. program 2. class 3. method 4. data

Analyze the following code and choose the best answer: public class Foo { private int x; public static void main(String[] args) { Foo foo = new Foo(); System.out.println(foo x); } } 1. Since x is private, it cannot be accessed from an object foo. 2. Since x is defined in the class Foo, it can be accessed by any method inside the class without using an object. You can write the code to access x without creating an object such as foo in this code. 3. Since x is an instance variable, it cannot be directly used inside a main method. However, it can be accessed through an object such as foo in this code. 4. You cannot create a self-referenced object; that is, foo is created inside the class Foo.

Analyze the following code: class Test{ privat double i; public Test(double i) { this.t(); this.i = i; } public Test() { System.out.println("Default constructor"); this(1); } public void t() { System.out.println("Invoking t"); } } 1. this.t() may be replaced by t(). 2. this.i may be replaced by i. 3. this(1) must be called before System.out.println("Default constructor"). 4. this(1) must be replaced by this(1.0).

________ is invoked to create an object. 1. A constructor 2. The main method 3. A method with a return type 4. A method with the void return type

________ can be accessed from any instance method in the class. 1. A local variable 2. An instance variable 3. A static variable

________ can be accessed from any static method in the class. 1. A local variable 2. An instance variable 3. A static variable

You use the ________ operator to access members of an object. . () * %

You should add the static keyword in the place of ? in Line ________ in the following code: public class Test{ private int age; public ? int square(int n) { return n*n; } public ? int getAge() { } } 1. in line 4 2. in line 8 3. in both line 4 and line 8 4. none

T/F You cannot use the private modifier on classes.

You can declare two variables with the same name in ________. 1. a method one as a formal parameter and the other as a local variable 2. a block 3. two nested blocks in a method (two nested blocks means one being inside the other) 4. different methods in a class

Which of the following statements are true? 1. A default constructor is provided automatically if no constructors are explicitly declared in the class. 2.At least one constructor must always be defined explicitly. 3. Every class has a default constructor. 4. The default constructor is a no-arg constructor.

Which is the advantage of encapsulation? 1. Only public methods are needed. 2. Making the class final causes no consequential changes to other code. 3. It changes the implementation without changing a class's contract and causes no consequential changes to other code. 4. It changes a class's contract without changing the implementation and causes no consequential changes to other code.

Suppose you declare Date d. d is now called ________. 1. an object 2. a reference variable for an object 3. an object value 4. a variable that holds an integer value

T/F Each class in the file is compiled into a separate bytecode file.

The pillars of object-oriented programming are: