3252 Final Exam Flash Cards

Front 1

Which of the following is not one of the three general types of computer languages?

Back 1

Spoken languages.

Front 2

Which of the following is not a Java primitive type?

Back 2

real

Front 3

________ models software in terms similar to those that people use to describe real-world objects.

Back 3

Object-oriented design

Front 4

All import declarations must be placed

Back 4

before the class declaration.

Front 5

Which class provides prebuilt dialog boxes that enable programs to display windows containing messages (such windows are called message dialogs)?

Back 5

JOptionPane

Front 6

What is the result value of c at the end of the following code segment?

int c = 8;

c++;

++c;

c %= 5;

Back 6

0

Front 7

How many times is the body of the loop below executed?

int counter = 1;

while ( counter > 20 ) {

// body of loop

counter = counter - 1;

} // end while

Back 7

0

Front 8

End-of-line comments that should be ignored by the compiler are denoted using

Back 8

Two forward slashes ( // )

Front 9

Which of the following is a Scanner method?

Back 9

nextLine.

Front 10

Which of the following is not one of the six logical units of a computer?

Back 10

Printer.

Front 11

(True / False) Compilers translate high-level language programs into machine language programs.

Back 11

True

Front 12

(True / False) The following segment is a proper way to call the method readData four times?

int i = 0;

while ( i < 4 ) {

readData();

i = i + 1; } // end while

Back 12

True

Front 13

(True / False) The following does not contain a syntax error?

System.out.println( "Hello world!" );

Back 13

True

Front 14

What is the difference between a float and a double?

Back 14

Double variables store numbers with larger magnitude and finer detail.

Front 15

What does the expression x %= 10 do?

Back 15

Divides x by 10 and stores the remainder in x.

Front 16

Which command compiles the Java source code file Welcome.java?

Back 16

javac Welcome.java

Front 17

What is output by the following Java code segment?

int temp = 180;

if ( temp > 90 ) {

System.out.println( "This porridge is too hot.");

// cool down

temp = temp – ( temp > 150 ? 100 : 20 );

} // end if

else {

if ( temp < 70 ) {

System.out.println("This porridge is too cold.");

// warm up

temp = temp + (temp < 50 ? 30 : 20);

} // end if

} // end else

if ( temp == 80 )

System.out.println( "This porridge is just right!");

Back 17

None of the above

Front 18

What is output by the following Java code segment?

int temp = 180;

while ( temp != 80 ) {

if ( temp > 90 ) {

System.out.print( "This porridge is too hot! " ); // cool down

temp = temp – ( temp > 150 ? 100 : 20 );

} // end if

else {

if ( temp < 70 ) {

System.out.print("This porridge is too cold! "); // warm up

temp = temp + (temp < 50 ? 30 : 20);

} // end if

} // end else

} // end while

if ( temp == 80 )

System.out.println( "This porridge is just right!" );

Back 18

This porridge is too hot! This porridge is just right!

Front 19

(True / False) Information in the memory unit is persistent—it is retained when the computer's power is turned off.

Back 19

False

Front 20

(True / False) Declaration structure is NOT a control structure

Back 20

True

Front 21

(True / False) The following will count down from 10 to 1 correctly?

for ( int j = 10; j >= 1; j-- )

Back 21

True

Front 22

(True / False) A continue statement proceeds with the next iteration of the immediately enclosing while, for, do…while statement

Back 22

True

Front 23

What is another way to write the code segment below:

if ( gender == 1 ) {

if ( age >= 65 )

++seniorFemales;

} // end if

Back 23

if ( gender == 1 && age >= 65 )

++seniorFemales;

Front 24

The control variable of a counter-controlled loop should be declared as ________to prevent errors.

Back 24

int

Front 25

For the code segment below:

switch( q ) {

case 1:

System.out.println( "apple" );

break;

case 2:

System.out.println( "orange" );

break;

case 3:

System.out.println( "banana" );

break;

case 4:

System.out.println( "pear" );

case 5:

System.out.println( "grapes" );

default:

System.out.println( "kiwi" );

} // end switch

Which of the following values for q will result in kiwi being included in the output?

Back 25

Anything greater than or equal to 4.

Front 26

(True / False) The break statement, when executed in a while, for or do…while, skips the remaining statements in the loop body and proceeds with the next iteration of the loop.

Back 26

False

Front 27

Suppose variable gender is MALE and age equals 60, how is the following expression evaluated?

( gender == FEMALE ) && ( age >= 65 )

Back 27

The condition ( gender == FEMALE ) is evaluated first and the evaluation stops immediately.

Front 28

(True / False) The body of a do…while loop is always executed at least once.

Back 28

True

Front 29

To exit out of a loop completely, and resume the flow of control at the next line in the method, use _______.

Back 29

A break statement.

Front 30

Attempting to access an array element out of the bounds of an array, causes a(n)

Back 30

ArrayIndexOutOfBoundsException.

Front 31

Arrays are:

Back 31

fixed-length entities

Front 32

The preferred way to traverse a two-dimensional array is to use

Back 32

two nested for statements.

Front 33

Consider the array:

s[ 0 ] = 7

s[ 1 ] = 0

s[ 2 ] = -12

s[ 3 ] = 9

s[ 4 ] = 10

s[ 5 ] = 3

s[ 6 ] = 6

The value of s[ s[ 6 ] - s[ 5 ] ] is:

Back 33

9

Front 34

Which statement correctly passes the array items to method takeArray? Array items contains 10 elements

Back 34

takeArray( items )

Front 35

A programmer must do the following before using an array:

Back 35

declare then create the array.

Front 36

Consider the program below:

public class Test {

public static void main( String[] args ) {

int[] a;

a = new int[ 10 ];

for ( int i = 0; i < a.length; i++ )

a[ i ] = i + 2;

int result = 0;

for ( int i = 0; i < a.length; i++ )

result += a[ i ];

System.out.printf( "Result is: %d\n", result );

} // end main

} // end class Test

The output of this program will be:

Back 36

Result is: 65.

Front 37

Which method call converts the value in variable stringVariable to an integer?

Back 37

Integer.parseInt( stringVariable )

Front 38

What do the following statements do?

double[] array;

array = new double[ 14 ];

Back 38

Create a double array containing 14 elements.

Front 39

In this question, assume a class, Book, has been defined. What is a set of statements that creates an array of Book objects?

Back 39

Book[] books;books = new Book[ numberElements ];

Front 40

Static class variables:

Back 40

are shared by all objects of a class.

Front 41

(True / False) Variables (or fields) should usually be private

Back 41

True

Front 42

Instance variables declared final do not or cannot:

Back 42

Be modified.

Front 43

Having a this reference allows

Back 43

all of the above

Front 44

When should a program explicitly use the this reference?

Back 44

Accessing a field that is shadowed by a local variable.

Front 45

(True / False)

Objects are marked for garbage collection by method finalize.

Back 45

False

Front 46

A package is:

Back 46

all of the above

Front 47

The import declaration import *; ________.

Back 47

causes a compilation error

Front 48

A class within a package must be declared public if

Back 48

It will be used by classes that are not in the same package

Front 49

When no access modifier is specified for a method or variable, the method or variable:

Back 49

Has package access

Front 50

Failure to prefix the superclass method name with the keyword super and a dot (.) separator when referencing the superclass’s method causes ________.

Back 50

infinite recursion

Front 51

Superclass methods with this level of access cannot be called from subclasses.

Back 51

private

Front 52

The default implementation of method clone of Object performs a ________.

Back 52

shallow copy

Front 53

Which of the following keywords allows a subclass to access a superclass method even when the subclass has overridden the superclass method?

Back 53

super

Front 54

Every class in Java, except ________, extends an existing class.

Back 54

Object

Front 55

Which superclass members are inherited by all subclasses of that superclass?

Back 55

protected instance variables and methods

Front 56

Using the protected keyword gives a member:

Back 56

package access

Front 57

When a subclass constructor calls its superclass constructor, what happens if the superclass’s constructor does not assign a value to an instance variable?

Back 57

The program compiles and runs because the instance variables are initialized to their default values

Front 58

Overriding a method differs from overloading a method because:

Back 58

Overridden methods have the same signature.

Front 59

An advantage of inheritance is that:

Back 59

Objects of a subclass can be treated like objects of their superclass.

Front 60

Declaring a method final means

Back 60

it cannot be overridden

Front 61

Which statement best describes the relationship between superclass and subclass types?

Back 61

A subclass reference can be assigned to a superclass variable, but a superclass reference cannot be assigned to a subclass variable

Front 62

Polymorphism allows for specifics to be dealt with during:

Back 62

execution

Front 63

Non-abstract classes are called:

Back 63

concrete classes

Front 64

(True / False) Methods in an abstract class are implicitly final

Back 64

False

Front 65

Polymorphism enables you to:

Back 65

program in the general

Front 66

(True / False - about abstract superclasses)

Abstract superclasses may contain data

Back 66

True

Front 67

Consider the abstract superclass below:

public abstract class Foo {

private int a;

public int b;

public Foo( int aVal, int bVal ) {

a = aVal; b = bVal;

} // end Foo constructor

public abstract int calculate(); }

// end class Foo

Any concrete subclass that extends class Foo:

Back 67

Both (a) and (b)

Front 68

A(n) __________ class cannot be instantiated.

Back 68

abstract

Front 69

Which keyword is used to specify that a class will define the methods of an interface?

Back 69

implements

Front 70

(True / False)

The try block should contain statements that may throw an exception

Back 70

True

Front 71

When a __________ method or block is running on an object, the object is locked so no other such method can run on that object at the same time

Back 71

synchronized

Front 72

The preferred means of creating multithreaded Java applications is by implementing the ________ interface. An object of a class that implements this interface represents a task to perform.

Back 72

Runnable

Front 73

A new thread begins its life cycle by transitioning to the __________ state

Back 73

new

Front 74

(True / False) ExecutorService is an object that can be run in a separate thread

Back 74

False

Front 75

All exception classes inherit, either directly or indirectly, from

Back 75

class Throwable

Front 76

The main method executes in the ________ thread of execution.

Back 76

main

Front 77

To catch an exception, the code that might throw the exception must be enclosed in a

Back 77

try block

Front 78

In the catch block below, what is arithmeticException?

catch (ArithmeticException arithmeticException)

{ System.err.printf( arithmeticException ); }

// end catch

Back 78

The name of catch block’s exception parameter

Front 79

An uncaught exception

Back 79

is an exception that occurs for which there are no matching catch clauses.

Front 80

One generic Stack class could be the basis for creating many Stack classes, e.g., Stack, Stack and Stack. These classes are known as __________

Back 80

parameterized classes

Front 81

The classes and interfaces which comprise the collections framework are members of package ________

Back 81

java.util

Front 82

(True / False)

A non-generic class cannot be derived from a generic class

Back 82

False

Front 83

When a generic class is instantiated without specifying a type argument, it is said to have a __________

Back 83

raw type

Front 84

__________ enable programmers to specify, with a single method declaration, a set of related methods

Back 84

Generic methods

Front 85

The collections framework algorithms are __________, i.e., each of these algorithms can operate on objects that offer given interfaces without concern to the underlying implementations

Back 85

polymorphic

Front 86

When the compiler translates a generic method into Java bytecodes, it uses __________ to replace the type parameters with actual types

Back 86

erasure

Front 87

Collections method sort that accepts a List as an argument sorts the elements of a List, which must implement the __________ interface.

Back 87

Comparable

Front 88

A(n) __________ allows a program to walk through the collection and remove elements from the collection.

Back 88

Iterator

Front 89

(True / False)

A List cannot contain duplicate elements

Back 89

False

Front 90

A JEditorPane generates HyperlinkEvents only if it is __________

Back 90

uneditable

Front 91

A(n) _________ is thrown when a String that is not in proper URL format is passed to a URL constructor

Back 91

MalformedURLException

Front 92

If an ObjectInputStream is used to read information from the server, an __________ is generated when the client attempts to read a value from a stream on which end-of-stream is detected

Back 92

EOFException

Front 93

__________ sockets and the __________ protocol are more desirable for the vast majority of Java programmers.

Back 93

Stream, TCP

Front 94

(True / False)

Normally, an applet can read files on any server that can be reached over the network

Back 94

False

Front 95

A(n) __________ is thrown when a server address indicated by a client cannot be resolved

Back 95

UnknownHostException

Front 96

Using a URL as an argument to the __________ method of interface AppletContext causes the browser in which an applet is executing to display the URL

Back 96

showDocument

Front 97

(True / False)

UDP is a connection-oriented protocol

Back 97

False

Front 98

(True / False)

With datagram sockets a process establishes a connection to another process

Back 98

False

Front 99

Once the ServerSocket is created, the server can listen indefinitely (or block) for an attempt by a client to connect. This is accomplished with a call to the ServerSocketmethod __________

Back 99

accept

Front 100

Which of the following can be an argument to a method?

a. Constants.

b. Variables.

c. Expressions.

d. All of the above.

Back 100

All of the above

Front 101

(True / False)

\ is an escape character

Back 101

True

Front 102

Overloaded methods always have the same _________.

a. method name.

b. return type.

c. number of parameters.

d. order of the parameters.

Back 102

method name.

Front 103

An overloaded method is one that

a. has a different name than another method, but the same parameters.

b. has the same name as another method, but different parameters (by number, types or order of the types).

c. has the same name and parameters as a method defined in another class.

d. has the same name and parameters, but a different return type as another method.

Back 103

b. has the same name as another method, but different parameters (by number, types or order of the types).

Front 104

Which command below runs TestProgram, and passes in the values files.txt and 3?

a. java TestProgram files.txt 3.

b. java TestProgram files.txt, 3.

c. java TestProgram "files.txt", "3".

d. java TestProgram (the arguments files.txt and 3 were passed in when the application was compiled).

Back 104

a. java TestProgram files.txt 3.

Front 105

A default constructor has how many parameters?

Back 105

0

Front 106

Which of the following is a valid fully qualified name?

a. Scanner.

b. java.Scanner.

c. util.Scanner.

d. java.util.Scanner.

Back 106

d. java.util.Scanner.

Front 107

Consider the classes below, declared in the same file:

class A {

int a;

public A() {

a = 7;

}

}

class B extends A {

int b;

public B() {

b = 8;

}

}

Which of the statements below is false?

a. Both variables a and b are instance variables.

b. After the constructor for class B executes, the variable a will have the value 7.

c. After the constructor for class B executes, the variable b will have the value 8.

d. A reference of type A can be treated as a reference of type B.

Back 107

d. A reference of type A can be treated as a reference of type B.

Front 108

Declaring main as ________ allows the JVM to invoke main without creating an instance of the class.

a. public.

b. void.

c. static.

d. final.

Back 108

c. static

Front 109

Which command executes the Java class file Welcome.class?

Back 109

java Welcome

Front 110

The throws clause of a method:

Back 110

specifies the exceptions a method throws.

Front 111

A constructor cannot

Back 111

specify a return type

Front 112

Which of the following is a double selection control statement?

Back 112

if..then..else

Front 113

A well-designed method

a. performs multiple unrelated tasks.

b. repeats code found in other methods.

c. contains thousands of lines of code.

d. performs a single, well-defined task.

Back 113

d. performs a single, well-defined task.

Front 114

A(n) ________ enables a program to read data from the user.

Back 114

Scanner

Front 115

What type of methods allow a client of a class to assign values to a private instance variable?

a. Get methods.

b. Replace methods.

c. Assign methods.

d. Set methods.

Back 115

d. Set methods

Front 116

Composition is sometimes referred to as a(n) ________.

a. is-a relationship.

b. has-a relationship.

c. many-in-one relationship.

d. one-to-many relationship.

Back 116

b. has-a relationship.

Front 117

Information is passed to a method in:

a. the method name.

b. that method's return.

c. the method body.

d. the arguments to the method.

Back 117

d. the arguments to the method.

Front 118

Suppose method1 is declared as

void method1 ( int a, float b )

Which of the following methods correctly overloads method1?

Back 118

void method1 ( float a, int b ).

Front 119

Which is a correct static method call of Math class method sqrt?

a. sqrt( 900 );.

b. math.sqrt( 900 );.

c. Math.sqrt( 900 );.

d. Math math = new Math(); math.sqrt( 900 );.

Back 119

c. Math.sqrt( 900 );.

Front 120

What is the name of the values the method call passes to the method for the parameters?

a. Arguments.

b. References.

c. Objects.

d. Values.

Back 120

a. Arguments

Front 121

Which of the following is NOT a control structure:

a. Declaration structure.

b. Repetition structure.

c. Sequence structure.

d. Selection structure.

Back 121

a. Declaration structure

Front 122

The _________ of a class are also called the public services or the public interface that the class provides to its clients.

a. public constructors.

b. public instance variables.

c. public methods.

d. All of the above.

Back 122

c. public methods

Front 123

Every Java application is composed of at least one:

a. local variable

b. instance variable

c. public class declaration

d. imported class

Back 123

c. public class declaration

Front 124

Calling a method of another object requires which item?

a. The dot separator.

b. Open and close braces.

c. The new keyword.

d. None of the above.

Back 124

a. The dot separator

Front 125

Which of the following initializer lists would correctly set the elements of array n?

a. int[] n = { 1, 2, 3, 4, 5 };

b. array n[ int ] = { 1, 2, 3, 4, 5 };

c. int n[ 5 ] = { 1; 2; 3; 4; 5 };

d. int n = new int( 1, 2, 3, 4, 5 );

Back 125

a. int[] n = { 1, 2, 3, 4, 5 };

Front 126

Counter-controlled repetition requires

a. A control variable and initial value.

b. A control variable increment (or decrement).

c. A condition that tests for the final value of the control variable.

d. All of the above.

Back 126

d. All of the above

Front 127

Which expression adds 1 to the element of array arrayName at index i?

a. ++arrayName[ i ]

b. arrayName++[ i ]

c. arrayName[ i++ ]

d. None of the above

Back 127

a. ++arrayName[ i ]

Front 128

When an exception occurs it is said to have been

Back 128

thrown

Front 129

Which primitive type can hold the largest value?

a.int

b.long

c.float

d.double

Back 129

d. double

Front 130

What is the size in bits of an int?

a.8

b.16

c.32

d.64

Back 130

c. 32

Front 131

Stacks are known as ________ data structures.

a. FIFO.

b. FILO.

c. LIFO.

d. LILO

Back 131

c. LIFO

Front 132

Which statement is false?

a.A generic class can be derived from a non-generic class

b.A generic class can be derived from another generic class

c.A non-generic class cannot be derived from a generic class

d.A generic method in a subclass can override a generic method in a superclass if both methods have the same signatures

Back 132

c. A non-generic class cannot be derived from a generic class

Front 133

Which of the following statements is true?

a.Interpreted programs run faster than compiled programs.

b.Compilers translate high-level language programs into machine language programs.

c.Interpreter programs typically use machine language as input.

d.None of the above.

Back 133

b.Compilers translate high-level language programs into machine language programs.

Front 134

What is the default value of a reference?

a.0

b.""

c.null

d.default

Back 134

c. null