In this example we shall show you how to generate a random Integer within a given range, using random() method of Math. The class Math contains methods for performing basic numeric operations such as the elementary exponential, logarithm, square root, and trigonometric functions. To generate a random Integer within a given range one should perform the following steps:
- Use
random()method of Math to get a double value with a positive sign, greater than or equal to 0.0 and less than 1.0. - Multiply the result to a number. For example, multiply the result to 100. The maximum of this is 100 and the minimum 0.
- You can also add a number to the result. For example add 50 to the result. Now the range is between 50 and 150,
as described in the code snippet below.
package com.javacodegeeks.snippets.core;
public class RandomIntWithinGivenRange {
public static void main(String args[]) {
// This example will return a random integer
// in the range [-50,50]
int random1 = (int)(Math.random()*100)-50;
System.out.println("Value 1 = " + random1);
// This example will return a random integer
// in the range [50,150]
int random2 = (int)(Math.random()*100)+50;
System.out.println("Value 2 = " + random2);
}
}
Output:
Value 1 = -43
Value 2 = 111
This was an example of how to generate a random Integer within a given range in Java.
