Java Tutorial/Class Definition/Static Import

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Static import

In Java 5 you can import static fields using the import static keywords.

Before Java 5, to use a static final field in the Calendar class, you must first import the Calendar class.



   <source lang="java">

import java.util.Calendar;</source>





Static importing the Math Class Methods

   <source lang="java">

import static java.lang.Math.sqrt; public class MainClass {

 public static void main(String[] arg) {
   System.out.println(sqrt(2));
 }

}</source>



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Use static import to bring sqrt() and pow() into view.

   <source lang="java">

import static java.lang.Math.pow; import static java.lang.Math.sqrt; class Hypot {

 public static void main(String args[]) {
   double side1, side2;
   double hypot;
   side1 = 3.0;
   side2 = 4.0;
   hypot = sqrt(pow(side1, 2) + pow(side2, 2));
   System.out.println("Given sides of lengths " + side1 + " and " + side2 + " the hypotenuse is "
       + hypot);
 }

}</source>