How to import Java packages
Description
In a Java source file, import statements occur immediately following the package statement and before class definitions.
Syntax
This is the general form of the import statement:
import pkg1[.pkg2].(classname|*);
* means including all classes under that package. For example,
import java.lang.*;
Any place you use a class name, you can use its fully qualified name, which includes its full package hierarchy.
For example, this fragment uses an import statement:
import java.util.*;
class MyDate extends Date {
}
The same example without the import statement looks like this:
class MyDate extends java.util.Date {
}
static import
In order to access static members, it is necessary to qualify references. For example, one must say:
double r = Math.cos(Math.PI * theta);
The static import construct allows unqualified access to static members.
import static java.lang.Math.PI;
or:
import static java.lang.Math.*;
Once the static members have been imported, they may be used without qualification:
double r = cos(PI * theta);
The static import declaration imports static members from classes, allowing them to be used without class qualification.