PACKAGES

Storing Packages in a File System

7.2.1

The hierarchical naming structure for packages is intended to be convenient

for organizing related packages in a conventional manner, but has no significance

in the Java language itself other than the prohibition against a package having a

subpackage with the same simple name as a type declared in that package. There

is no special access relationship in the Java language between a package named

oliver

 and another package named

oliver.twist

, or between packages named

evelyn.wood

 and

evelyn.Waugh

. For example, the code in a package named

oliver.twist

 has no better access to the types declared within package

oliver

than code in any other package.

7.2   Host Support for Packages

Each Java host determines how packages, compilation units, and subpackages are

created and stored; which top level package names are in scope in a particular

compilation; and which packages are accessible.

The packages may be stored in a local file system in simple implementations

of Java. Other implementations may use a distributed file system or some form of

database to store Java source and/or binary code.

7.2.1   Storing Packages in a File System

As an extremely simple example, all the Java packages and source and binary

code on a system might be stored in a single directory and its subdirectories. Each

immediate subdirectory of this directory would represent a top level package, that

is, one whose fully qualified name consists of a single simple name. The directory

might contain the following immediate subdirectories:

COM

gls

jag

java

wnj

where directory

java

 would contain the standard Java Application Programming

Interface packages that are part of every standard Java system; the directories

jag

,

gls

, and

wnj

 might contain packages that the three authors of this specification

created for their personal use and to share with each other within this small group;

and the directory

COM

 would contain packages procured from companies that used

the conventions described in  7.7 to generate unique names for their packages.

Continuing the example, the directory

java

 would probably contain at least

the following subdirectories:

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