Fizz Buzz in Java

Gradle setup

For our build.gradle file:

apply plugin: "java"
apply plugin: "eclipse"
apply plugin: "idea"

repositories {
    mavenCentral()
}

dependencies {
    testCompile "junit:junit:4.12"
}
test {
    testLogging {
        exceptionFormat = 'full'
        events = ["passed", "failed", "skipped"]
    }
}
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Setting up the Tests

Create file src/test/java/FizzBuzzTest.java:

import org.junit.Ignore;
import org.junit.Test;

import static org.junit.Assert.assertEquals;

public class FizzBuzzTest {
    @Test
    public void testReturnsIntAsString() {
        assertEquals("2", new FizzBuzz().run(2));
    }

    // @Ignore("Remove to run test")
    @Test
    public void testReturnsFizz() {
        assertEquals("Fizz", new FizzBuzz().run(3));
    }

    @Test
    public void testReturnsBuzz() {
        assertEquals("Buzz", new FizzBuzz().run(5));
    }

    @Test
    public void testReturnsFizzBuzz() {
        assertEquals("FizzBuzz", new FizzBuzz().run(15));
    }
}
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src/main/java/FizzBuzz.java

For our main Java file running FizzBuzz:

class FizzBuzz {
    String run(Integer input) {
        if (input % 15 == 0) {
            return "FizzBuzz";
        } else if (input % 3 == 0) {
            return "Fizz";
        } else if (input % 5 == 0) {
            return "Buzz";
        } else {
            return Integer.toString(input);
        }
    }
}
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Running tests

Run gradle test to compile and test our FizzBuzz class.