NAMES

Package Names

6.8.1

We recommend these conventions for use in all Java programs. However,

these conventions should not be followed slavishly if long held conventional

usage dictates otherwise. So, for example, the

sin

 and

cos

 methods of the class

java.lang.Math

 have mathematically conventional names, even though these

method names flout Java convention because they are short and are not verbs.

6.8.1   Package Names

Names of packages that are to be made widely available should be formed as

described in  7.7. Such names are always qualified names whose first identifier

consists of two or three uppercase letters that name an Internet domain, such as

COM

,

EDU

,

GOV

,

MIL

,

NET

,

ORG

, or a two letter ISO country code such as

UK

 or

JP

.

Here are examples of hypothetical unique names that might be formed under this

convention:

COM.JavaSoft.jag.Oak

ORG.NPR.pledge.driver

UK.ac.city.rugby.game

Names of packages intended only for local use should have a first identifier

that begins with a lowercase letter, but that first identifier specifically should not

be the identifier

java

; package names that start with the identifier

java

 are

reserved to JavaSoft for naming standard Java packages.

When package names occur in expressions:

If a package name is hidden by a field declaration, then

import

 declarations

( 7.5) can usually be used to make available the type names declared in that

package.

If a package name is hidden by a declaration of a parameter or local variable,

then the name of the parameter or local variable can be changed without

affecting other Java code.

The first component of a package name is normally not easily mistaken for a

type name, as a type name normally begins with a single uppercase letter.

(The Java language does not actually rely on case distinctions to determine

whether a name is a package name or a type name. It is not possible for a type

name to hide a package name.)

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