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Random Number Generation

Java provides a random number generation class java.util.Random.  There are two Random constructors.  The first takes as input nothing and the second takes as input a seed value.  The easiest way to generate random numbers is with the nextInt method.  It takes as input an int and generates a number between 0 (inclusive) and the specified number (exclusive).  An example follows:

import java.util.Random;

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

        Random r = new Random();
        int randnum = r.nextInt(25);

The example generates a number between 0 and 25.  In this example, 0 may be generated by the random number generator, but 25 will not be generated.

Notice that the first line of code is import java.util.Random.  This tells the compiler that the program will be using the Random class.  If you omit this line, your program will not compile.