Java Reference
In-Depth Information
Every type is represented by a number of different names. The actual
class or interface name is the
simple name
of the type. This is the
shortest name you could write in your program to represent a given
type. For example, the simple name of
java.lang.Object
is
Object
, the
simple name of the nested
EnTRy
interface in the
java.util.Map
interface
is
EnTRy
, the simple name of the type representing an array of
Object
in-
stances is
Object[]
, and the simple name of an array of
int
is
int[]
. All
types except for anonymous inner classes have simple names. You can
get the simple name of a type from the
Class
method
getSimpleName
.
The
canonical name
of a type is its full name, as you would write it
in your programs, including, if applicable, the package and enclosing
type in which the type was
declared.
For example, the canonical name
of
Object
is
java.lang.Object
; for the nested
EnTRy
interface it is
java.util.Map.Entry
; for an array of
Object
instances it is
java.lang.Object[]
; and for an array of
int
is
int[]
. In more specific
terms, the canonical name of a top-level class or interface is its package
name followed by dot, followed by its simple name. The canonical name
of a nested type is the canonical name of the type in which it is declared,
followed by dot, followed by its simple name. The canonical name of
an array type is the canonical name of its element type followed by
[]
.
Local inner classes and anonymous inner classes do not have canonical
names. You can get the canonical name of a type from the
Class
method
getCanonicalName
.
The canonical name is an example of a
fully qualified name
the simple
name qualified by the package and enclosing type, if applicable. While
simple names might be ambiguous in a given context, a fully qualified
name uniquely determines a type. Each type has only one canonical
name, but nested types (and so arrays of nested types) can have mul-
tiple fully qualified names. For example, the
java.util.SortedMap
inter-
face extends
java.util.Map
and inherits the nested
Entry
interface. Con-
sequently, you can identify the
Entry
type by the fully qualified name
java.util.SortedMap.Entry
.
The
binary name
of a class or interface (not array) is a name used
to communicate with the virtual machine, such as by passing it to
Class.forName
to ask the virtual machine for a specific
Class
object. The
