Import

• To access classes of one package in another package i.e use external classes without package qualification import feature is used.

• The classes and interfaces of one package are accessible in another package using import feature.

Example of import:

import java.util.Vector;
 
public class ImportDemo
{
   public ImportDemo()
   {
//Imported using keyword, hence able to access directly in the code without package qualification.
     Vector v = new Vector();
 
      // Package not imported, hence referring to it using the complete package.
      java.util.ArrayList list = new java.util.ArrayList();
   }
 
   public static void main(String arg[])
   {
      new ImportDemo();
   }
}

Static Import

• The static members of classes defined in one package can be used in another package without class qualification then static import feature is to be used.
• Static members of class are accessed.
• Advantage of Static import is it reduces code size but readability of program becomes difficult.
• Disadvantage of static import is,static members are used without class qualification it appears as it it is declared within called class therefore programmer cannot declare and define another variable of same name. 

Example of static import:

import static java.lang.System.*;  //Using Static Import
 
class StaticImportDemo
{
   public static void main(String args[])
   {
      //System.out is not used as it is imported using the keyword static
 
      out.println(Hello World);
   }
}