Java Reference
In-Depth Information
• Locale-specific formatting is an important part of internationalization—the process of custom-
izing your applications for users' various locales and spoken languages.
•
BigDecimal
gives you control over how values are rounded—by default all calculations are exact
and no rounding occurs. If you do not specify how to round
BigDecimal
values and a given value
cannot be represented exactly an
ArithmeticException
occurs.
• You can specify the rounding mode for
BigDecimal
by supplying a
MathContext
object (package
java.math
) to class
BigDecimal
's constructor when you create a
BigDecimal
. You may also pro-
vide a
MathContext
to various
BigDecimal
methods that perform calculations. By default, each
pre-configured
MathContext
uses so called “bankers rounding.”
•A
BigDecimal
's scale is the number of digits to the right of its decimal point. If you need a
Big-
Decimal
rounded to a specific digit, you can call
BigDecimal
method
setScale
.
Self-Review Exercise
8.1
Fill in the blanks in each of the following statements:
a) A(n) imports all
static
members of a class.
b)
String
class
static
method is similar to method
System.out.printf
, but re-
turns a formatted
String
rather than displaying a
String
in a command window.
c)
If a method contains a local variable with the same name as one of its class's fields, the
local variable
the field in that method's scope.
d)
The
public
methods of a class are also known as the class's
or
.
e)
A(n)
declaration specifies one class to import.
f)
If a class declares constructors, the compiler will not create a(n)
.
g)
An object's
method is called implicitly when an object appears in code where
a
String
is needed.
h)
Get
methods are commonly called
or
.
i)
A(n)
method tests whether a condition is true or false.
j)
For every
enum
, the compiler generates a
static
method called
that returns an
array of the
enum
's constants in the order in which they were declared.
k)
Composition is sometimes referred to as a(n)
relationship.
l)
A(n)
declaration contains a comma-separated list of
constants.
m) A(n)
variable represents classwide information that's shared by all the objects
of the class.
declaration imports one
static
member.
n)
A(n)
o)
The states that code should be granted only the amount of privilege and access
that it needs to accomplish its designated task.
p)
Keyword specifies that a variable is not modifiable after initialiation in a dec-
laration or constructor.
q)
A(n)
declaration imports only the classes that the program uses from a partic-
ular package.
r)
Set
methods are commonly called
because they typically change a value.
s)
Use class
to perform precise monetary calculations.
t)
Use the
statement to indicate that a problem has occurred.
Answers to Self-Review Exercise
8.1
a)
static
import on demand. b)
format
. c) shadows. d)
public
services,
public
interface.
e) single-type-import. f) default constructor. g)
toString
. h) accessor methods, query methods.
i) predicate. j)
values
. k)
has-a
. l)
enum
. m)
static
. n) single
static
import. o) principle of least
privilege. p)
final
. q) type-import-on-demand. r) mutator methods. s)
BigDecimal
. t)
throw
.
