Names - The Java Language Specification - page 143

6.5.3. Meaning of Package Names
The meaning of a name classified as a PackageName is determined as follows.
6.5.3.1. Simple Package Names
If a package name consists of a single Identifier , then this identifier denotes a top level
package named by that identifier.
If no top level package of that name is in scope (§ 6.3 ), then a compile-time error occurs.
6.5.3.2. Qualified Package Names
If a package name is of the form Q.Id , then Q must also be a package name. The package
name Q.Id names a package that is the member named Id within the package named by Q .
If Q does not name an observable package (§ 7.4.3 ), or Id is not the simple name of an ob-
servable subpackage of that package, then a compile-time error occurs.
6.5.4. Meaning of PackageOrTypeNames
6.5.4.1. Simple PackageOrTypeNames
If the PackageOrTypeName , Q , occurs in the scope of a type named Q , then the Pack-
ageOrTypeName is reclassified as a TypeName .
Otherwise, the PackageOrTypeName is reclassified as a PackageName . The meaning of
the PackageOrTypeName is the meaning of the reclassified name.
6.5.4.2. Qualified PackageOrTypeNames
Given a qualified PackageOrTypeName of the form Q.Id , if the type or package denoted
by Q has a member type named Id , then the qualified PackageOrTypeName name is reclas-
sified as a TypeName .
Otherwise, it is reclassified as a PackageName . The meaning of the qualified Pack-
ageOrTypeName is the meaning of the reclassified name.
6.5.5. Meaning of Type Names
The meaning of a name classified as a TypeName is determined as follows.
6.5.5.1. Simple Type Names
If a type name consists of a single Identifier , then the identifier must occur in the scope
of exactly one visible declaration of a type with this name, or a compile-time error occurs.
The meaning of the type name is that type.