Using java.util.Random class we can create random data such as boolean, integer, floats, double. First you’ll need to create an instance of the Random class. This class has some next***() methods that can randomly create the data.
package org.kodejava.util;
import java.util.Arrays;
import java.util.Random;
public class RandomDemo {
public static void main(String[] args) {
Random r = new Random();
// generate some random boolean values
boolean[] booleans = new boolean[10];
for (int i = 0; i < booleans.length; i++) {
booleans[i] = r.nextBoolean();
}
System.out.println(Arrays.toString(booleans));
// generate a uniformly distributed int random numbers
int[] integers = new int[10];
for (int i = 0; i < integers.length; i++) {
integers[i] = r.nextInt();
}
System.out.println(Arrays.toString(integers));
// generate a uniformly distributed float random numbers
float[] floats = new float[10];
for (int i = 0; i < floats.length; i++) {
floats[i] = r.nextFloat();
}
System.out.println(Arrays.toString(floats));
// generate a Gaussian normally distributed random numbers
double[] doubles = new double[10];
for (int i = 0; i < doubles.length; i++) {
doubles[i] = r.nextGaussian();
}
System.out.println(Arrays.toString(doubles));
}
}
The result of the code snippet above are:
[true, true, false, true, false, true, true, false, false, true]
[34195704, 1462972230, -475641915, -1531017612, 332184915, 1555901473, -276309016, 1433394157, -451221924, -1178823255]
[0.3040716, 0.28814012, 0.34028566, 0.021003246, 0.49158317, 0.37954164, 0.5403056, 0.54187375, 0.7157934, 0.5964742]
[1.051268591002577, -1.1283332046139989, 0.8351395528722437, -0.24598168031182968, 0.7123515366756693, -0.9661681996105319, -1.6107009669125059, 0.43994917963255387, 1.1309345726165914, 1.2321618489324313]
For an example to create random number using the Math.random() method see How do I create random number?.
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A programmer, recreational runner, live in the island of Bali, Indonesia. Programming in Java, Spring, Hibernate / JPA. You can support me working on this project, buy me a cup of coffee ☕ every little bit helps, thank you 🙏
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