True/False
Indicate whether the sentence or statement is true
or false.
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1.
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When
a Java program is executing, the computer's memory must hold all class templates in their compiled
form, variables that refer to objects, and objects as needed.
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2.
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The
identity of an object is simply the variable that references the object.
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3.
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A
class's implementation details can be changed radically without affecting any of its clients provided
its interface remains the same.
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4.
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In
Java it is illegal to have two variables referencing the same object.
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5.
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The
keyword public indicates that the class is accessible to all potential clients.
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6.
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Constructors do not have return types, but all other methods do.
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7.
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A
class can include only one constructor.
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8.
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A
method can only have one return statement.
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9.
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Variables declared within any compound statement enclosed in braces are said to have
local scope.
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10.
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Global variables can be reused within several different methods without causing a
conflict.
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11.
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A
good way to provide temporary storage is to use global variables.
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12.
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When
using turtle graphics, the color of a pen cannot be changed.
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13.
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The
OR operand evaluates to false if one operand is false.
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14.
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At a
minimum, test data should try to achieve complete code coverage, which means every line of code
should be executed at least once.
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15.
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Test
data at the limits of validity are called boundary conditions.
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16.
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Nested if statements offer an alternative to deal with a programs logical
complexity.
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17.
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It is
better to write code and then create a flow chart or truth table to verify the code.
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18.
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One
of the most common mistakes in nested if statements involves misplaced braces.
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19.
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Changing the indentation of if and else statements changes
the logic of the code.
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20.
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Since
overusing braces clutters the code, only use braces when needed.
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21.
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Arithmetic overflow results when the range of a given number is
exceeded.
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22.
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Java
uses complete evaluation, in which all parts of a Boolean expression are always
evaluated.
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23.
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Complete code coverage in testing will test all logical paths through a
program.
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24.
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The
following nested if statements are equivalent:
if ( it is 3:00 )
if ( it is 3:00
)
if ( it is Monday )
if ( it is Monday ){
go home
go
home
go to the
gym go to the
gym
}
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25.
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If
braces are removed from a nested if/else statement, Java pairs the else with the
closest preceding if.
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26.
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The
structures of a Graphical User Interface (GUI) programs and a terminal-based programs do not
differ.
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27.
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Developing GUI's in Java is usually not complicated.
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28.
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A
double field object displays text in a window.
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29.
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A
button object activates a method when clicked by a user.
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30.
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A
text area is a convenient device for popping up messages outside an application's main
window.
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31.
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A
character literal is enclosed within double quotes.
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32.
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The
readChar method in the KeyboradReader class will only read the first character entered on a
line.
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33.
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The
grid of a window object will automatically adjust itself to the needed number of rows and
columns.
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34.
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The
4th parameter in an add method specifies the width of the
object.
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35.
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A
programmer cannot set the height and width of a message box.
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Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.
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36.
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The
process of creating a new object is called: a. | encapsulation | c. | instantiation | b. | class | d. | new | | | | |
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37.
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Java
deletes objects from memory in a process called: a. | deletion | c. | memory allocation | b. | garbage
collection | d. | memory
dumping | | | | |
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38.
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Which
characteristic of an object says that at any moment its instance variables have particular
values. a. | state
| c. | identity | b. | behavior | d. | instantiation | | | | |
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39.
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What
is the list of the methods supported by the server referred to as? a. | encapsulation | c. | behavior | b. | state | d. | interface | | | | |
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40.
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Messages that change an object's state are called: a. | accessors | c. | mutators | b. | constructors | d. | methods | | | | |
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41.
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What
is the name of a method that indicates how to initialize a new object? a. | initializer | c. | mutator | b. | constructor | d. | accessor | | | | |
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42.
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If
class A extends class B, class B is the _________ of class A. a. | parent | c. | nephew | b. | child | d. | subclass | | | | |
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43.
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If a
class A omits the extends <some class> clause, which class is assumed to be the
superclass of class A. a. | Object | c. | System | b. | KeyboardReader | d. | Math | | | | |
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44.
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What
are activated when the keyword new is used and at no other time. a. | accessors | c. | constructors | b. | mutators | d. | methods | | | | |
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45.
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A
method whose implementing code is omitted is called a: a. | accessor | c. | helper | b. | mutator | d. | stub | | | | |
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46.
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Values passed to a method when it is invoked are called: a. | actual
parameters | c. | constructors | b. | formal parameters | d. | initial values | | | | |
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47.
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To
provide temporary working storage for data in a method a programmer can declare: a. | global
variables | c. | instance
variables | b. | local variables | d. | classes | | | | |
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48.
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The
________ of a variable is that region of the program within which it can validly appear in lines of
code. a. | lifetime | c. | value | b. | type | d. | scope | | | | |
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49.
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Variables defined as instance variables of a class are referred to
as: a. | local | c. | temporary | b. | global | d. | public | | | | |
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50.
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The
_________ of a variable is the period during which it can be used. a. | time
period | c. | lifetime | b. | scope | d. | type | | | | |
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51.
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Which
of the following is NOT one of the 3 logical operators introduced in this chapter.
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52.
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If
the operator AND is used, which of the following will make the whole condition true? a. | first operand
true, second operand false | c. | both operands
true | b. | first operand
false, second operand true | d. | both operands
false | | | | |
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53.
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What
is the precedence of the logical operator OR ( || )?
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54.
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Which
of the following is the Java symbol for logical AND?
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55.
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The
sets of test data that exercise a program in the same manner are said to belong to the
same: a. | code
coverage | c. | equivalence
class | b. | set | d. | boundary condition | | | | |
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56.
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It is
common for programs to fail around which points? a. | boundary condition points | c. | equivalence class points | b. | extreme
condition points | d. | no
points | | | | |
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57.
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Reformatting the first if/else statement into the second is
called:
( 1
)
( 2 )
if(
)
if( )
statement
statement
else
else if ()
if(
)
statement
statement a. | extended if
statement | c. | two-way if
statement | b. | one-way if statement | d. | many-way if statement | | | | |
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58.
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A
program that tolerates errors in user inputs and recovers gracefully is: a. | combinatorial | c. | clear | b. | robust | d. | solid | | | | |
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59.
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When
a program attempts to add one to the most positive integer in the range what value is
yielded. a. | 0 | c. | null | b. | the most negative integer | d. | a random integer | | | | |
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60.
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In
general, how many combinations of true and false are there for n operands in a truth
table.
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61.
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What
is the symbol for the NOT operator in Java?
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62.
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Which
of the following Boolean expressions is equivalent to: !( p && q
) a. | !p &&
!q | c. | p &&
!q | b. | !p &&
q | d. | !p ||
!q | | | | |
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63.
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The
approach in which evaluation of a Boolean expression stop as soon as possible is
called: a. | truth
evaluation | c. | complete
evaluation | b. | short-circuit evaluation | d. | ASAP-evaluation | | | | |
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64.
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What
is used in Java to determine if two string objects contain equal strings. a. | == | c. | equals(
) | b. | compare(
) | d. | isEqual(
) | | | | |
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65.
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An
Artificial Intelligence program that learns a set of rules is called a: a. | softbot | c. | smart
program | b. | robot | d. | neural net | | | | |
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66.
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A GUI
program is ________, meaning that it is inactive until the user clicks a button or selects a menu
option. a. | prompt
driven | c. | user
friendly | b. | robust | d. | event driven | | | | |
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67.
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What
type of input technique asks the user if there are more inputs are each set of
inputs? a. | count-controlled | c. | sentinel-controlled | b. | query-controlled | d. | user-controlled | | | | |
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68.
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What
is Java's standard GUI-building toolkit?
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69.
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A GUI
program must be a subclass of which class? a. | Frame | c. | JButton | b. | JLabel | d. | GBFrame | | | | |
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70.
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A
________ object can accept user input and/or display program output. a. | button | c. | button | b. | double field | d. | GBFrame | | | | |
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71.
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What
does the addLabel() method NOT do? a. | activate methods | c. | position a label object | b. | initialize a
label object | d. | instantiate a
label object | | | | |
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72.
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The
getNumber and _________ methods read and write numbers from and to numeric fields,
respectively. a. | sendNumber | c. | initializeNumber | b. | writeNumber | d. | setNumber | | | | |
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73.
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The
difference between a text field object and a text area object is: a. | a text field can
handle several lines of text | b. | a text field can only handle integers | c. | a text area can
handle several lines of text | d. | no difference | | |
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74.
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What
does the isValid method do in the integer field class? a. | determines
whether the number entered is positive | b. | determines whether the number entered is a valid
integer | c. | determines whether a value was
entered | d. | determines whether the object was instantiated
correctly | | |
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75.
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Which
method is not implemented by all window controls? a. | isValid | c. | setEnabled | b. | setVisible | d. | requestFocus | | | | |
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76.
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What
is the Swing toolkit's default look and feel? a. | Metal | c. | Windows | b. | Motif | d. | Mac | | | | |
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77.
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Which
of the following is NOT a justification in the BreezySwing method Format.justify( ...
)? a. | Left
| c. | Middle | b. | Right | d. | Center | | | | |
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78.
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How
many blank spaces appear in front of the number in the output of the following
code:
System.out.println( Format.justify( 'r',
3.25823, 10, 3 ) );
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79.
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A
___________ shows the relationship between a method and its helper methods. a. | flow
chart | c. | pseudocode | b. | truth table | d. | structure chart | | | | |
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80.
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What
is the minimum number of columns a window will have if the following Java instruction is
included:
doubleField field3 = addDoubleField( 0, 4, 2,
1, 3);
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81.
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What
does the first parameter of an add method specify? a. | the object's
initial value | c. | the object's row
number | b. | the object's height | d. | the object's column number | | | | |
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82.
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Labels are part of Swing, whereas __________ are derived from objects in
Swing. a. | command
buttons | c. | text
areas | b. | double fields | d. | text fields | | | | |
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83.
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What
does the setEnabled( true ) method do? a. | move focus to
the control | c. | makes control
visible | b. | hides the control | d. | sets the control to receive user
input | | | | |
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84.
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Which
of the following is NOT a method of a JButton object? a. | setText | c. | setEnabled | b. | setLabel | d. | setVisible | | | | |
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85.
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What
is the correct Java code for the following output.( note: underscores "_" are designated as
blanks for readability )
_ _ _ _ 3.963 a. | System.out.println( Format.justify( 'l', 3.96349, 9, 3 ) ); | b. | System.out.println( Format.justify( 'c', 3.963, 8, 4 ) ); | c. | System.out.println( Format.justify( 'r', 3.96349, 9, 3 ) ); | d. | System.out.println( Format.justify( 'r', 3.963, 9, 5 ) ); | | |
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Completion
Complete each sentence or
statement.
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86.
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An
object has _________ as defined by the methods of its class.
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87.
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If a
reference variable of an object is set to _______, and no other variable points to that object, the
computer reclaims the object's memory during garbage collection.
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88.
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Using
the visibility modifier __________ for instance variables is an important aspect of information
hiding.
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89.
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Constructors with empty parameter lists are called ___________
constructors.
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90.
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Parameters listed in a method's definition are called ________
parameters.
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91.
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Methods that are usually private that help break down tasks to reduce complexity are
called _________ methods.
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92.
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A
programmer uses the symbol ______ to refer to the current instance of a class within that class's
definition.
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93.
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The
default width of a pen in turtle graphics is two ________, or picture elements.
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94.
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The
operator _____ changes the truth value of a condition to the opposite value, i.e. if the operand is
true, then this operator makes the condition false.
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95.
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When
a loop is placed within another loop it is called a __________ loop.
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96.
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A
________ _________ can determine the value of any complex Boolean expression.
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Short Answer
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97.
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When
messages are sent, which two objects are involved?
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98.
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Assuming A is true, B is false and C is true, what is the value of the following
boolean expression?
( A && !B ) ||
!C
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99.
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What
two packages need to be imported to build a GUI program?
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