A package declaration in a compilation unit specifies the name (§6.2) of the package to which the compilation unit belongs.
PackageDeclaration:
package
PackageName;
The package name mentioned in a package declaration must be the fully qualified name (§6.7) of the package.
If a type named T is declared in a compilation unit of a package whose fully qualified name is P, then the fully qualified name of the type is P.
T; thus in the example:
package wnj.points; class Point { int x, y; }
the fully qualified name of class Point
is wnj.points.Point
.