Java Math random() Method

The java.lang.Math.random() method returns a pseudorandom double type number greater than or equal to 0.0 and less than 1.0. When this method is first called, it creates a single new pseudorandom-number generator, exactly as if by the expression new java.util.Random. 

Declaration of Java Math random()

Below is the declaration of java.lang.Math.random() method is mentioned below:

public static double random()

Return Type

This method returns a pseudorandom double greater than or equal to 0.0 and less than 1.0.

Java Math random() Method with Examples

Example 1:To show the working of java.lang.Math.random() method. 

java

// Java program to demonstrate working
// of java.lang.Math.random() method
import java.lang.Math;

// Driver Class
class Gfg1 {
    // driver code
    public static void main(String args[])
    {
        // Generate random number
        double rand = Math.random();

        // Output is different everytime this code is executed
        System.out.println("Random Number:" + rand);
    }
}

Output:

0.5568515217910215

Example 2:To show the working of java.lang.Math.random() method. 

Now to get random integer numbers from a given fixed range, we take a min and max variable to define the range for our random numbers, both min and max are inclusive in the range.

java

// Java program to demonstrate working
// of java.lang.Math.random() method
import java.lang.Math;

class Gfg2 {
    // driver code
    public static void main(String args[])
    {
        // define the range
        int max = 10;
        int min = 1;
        int range = max - min + 1;

        // generate random numbers within 1 to 10
        for (int i = 0; i < 10; i++) {
            int rand = (int)(Math.random() * range) + min;

            // Output is different everytime this code is executed
            System.out.println(rand);
        }
    }
}

Output:

6
8
10
10
5
3
6
10
4
2