A source file may start with a package declaration:
package foo.bar fun baz() {} class Goo {} // ...
All the contents (such as classes and functions) of the source file are contained by the package declared. So, in the example above, the full name of baz()
is foo.bar.baz
, and the full name of Goo
is foo.bar.Goo
.
If the package is not specified, the contents of such a file belong to "default" package that has no name.
A number of packages are imported into every Kotlin file by default:
Additional packages are imported depending on the target platform:
Apart from the default imports, each file may contain its own import directives. Syntax for imports is described in the grammar.
We can import either a single name, e.g.
import foo.Bar // Bar is now accessible without qualification
or all the accessible contents of a scope (package, class, object etc):
import foo.* // everything in 'foo' becomes accessible
If there is a name clash, we can disambiguate by using as keyword to locally rename the clashing entity:
import foo.Bar // Bar is accessible import bar.Bar as bBar // bBar stands for 'bar.Bar'
The import
keyword is not restricted to importing classes; you can also use it to import other declarations:
Unlike Java, Kotlin does not have a separate "import static" syntax; all of these declarations are imported using the regular import
keyword.
If a top-level declaration is marked private, it is private to the file it's declared in (see Visibility Modifiers).
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Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/docs/reference/packages.html