Import Math Class in Java

How to import math class in Java? The Math class in Java is available in java.lang package. Since java.lang package is the default package to every Java program, therefore there is no need to import Math class explicitly in the program.

But all variables and methods of Math class are static. There are two ways to access static variables or methods of Math class,

An example of directly using the class name to import math class in Java,

public class Test {
   public static void main(String[] args) {

      System.out.println(Math.PI); // 3.141592653589793
      System.out.println(Math.E); // 2.718281828459045

      System.out.println(Math.pow(2, 3)); // 8.0
      System.out.println(Math.exp(1)); // 2.718281828459045
      System.out.println(Math.log10(10)); // 1.0

      System.out.println(Math.sqrt(64)); // 8.0
      System.out.println(Math.cbrt(64)); // 4.0

      System.out.println(Math.abs(-20)); // 20
      System.out.println(Math.max(10, -20)); // 10
      System.out.println(Math.min(10, -20)); // -20
   }
}

Output:-

3.141592653589793
2.718281828459045
8.0
2.718281828459045
1.0
8.0
4.0
20
10
-20

Let us see a Java program to demonstrate how to import math class in Java and use them in our program?

Java Program to Find the Area of a Circle.

public class CircleArea{
   public static void main(String[] args) {
      int radius = 10;

      // circle area = π * r * r
      double area = Math.PI * Math.pow(radius, 2);

      // display area
      System.out.println(area);
   }
}

Output:-

314.1592653589793

See all variables and methods of Math class in Java with many examples:- Math class in Java

Also see:- Top 100+ Java Programming Examples With Output, Top 40+ Array Programs in Java

Static Import Math class in Java

We can import Math class statically and then invoke static members without calling through its class name. Learn more about how static import works, and the difference between normal import vs static import in Java:- Static import in Java.

Statement to import Math class all static members:- import static java.lang.Math.*;

The “import static java.lang.Math.*;” statement will import all static variables and methods of the Math class.

Example of static import math class in Java

import static java.lang.Math.*;
public class Test {
   public static void main(String[] args) {

      System.out.println(PI); // 3.141592653589793
      System.out.println(E); // 2.718281828459045

      System.out.println(pow(2, 3)); // 8.0
      System.out.println(exp(1)); // 2.718281828459045
      System.out.println(log10(10)); // 1.0

      System.out.println(sqrt(64)); // 8.0
      System.out.println(cbrt(64)); // 4.0

      System.out.println(abs(-20)); // 20
      System.out.println(max(10, -20)); // 10
      System.out.println(min(10, -20)); // -20
   }
}

If we want to import only a particular static member using the static import concept then we have to use the following syntax:- import static package.className.staticMember;

It will import only a particular static member. Example:- import static Math.PI; to import only PI variable, import static Math.sqrt; to import only sqrt() method.

Program:- Java Program to find the area of a circle through a static import math class in Java,

import static java.lang.Math.PI;
import static java.lang.Math.pow;
public class Test{
   public static void main(String[] args) {
      int radius = 10;

      // circle area = π * r * r
      double area = PI * pow(radius, 2);

      // display area
      System.out.println(area);
   }
}

Output:-

314.1592653589793

Note that the Math class contains several methods having multiple overloaded forms. For example abs(), max() and min() methods contains 4 overloaded forms per method.

The overloaded forms of Math.max() are,

  • public static int max(int a, int b)
  • public static long max(long a, long b)
  • public static float max(float a, float b)
  • public static double max(double a, double b)

If the method contains several overloaded forms and we are using static import to import only that particular method then all of its overloaded forms are also imported.

import static java.lang.Math.max;
public class Test{
   public static void main(String[] args) {

      // int max(int a, int b)
      System.out.println(max(10, 20)); // 20

      // long max(long a, long b)
      System.out.println(max(40L, 30L)); // 40

      // float max(float a, float b)
      System.out.println(max(10.5F, 19.9F)); // 19.9

      // double max(double a, double b)
      System.out.println(max(25.0, 15.5)); // 25.0
   }
}

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