FizzBuzzSourceGenerator.java

import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.util.stream.Collectors;
import java.util.stream.IntStream;

public class FizzBuzzSourceGenerator {
    public static void main(String[] args) throws FileNotFoundException {
        String sourceText = "public class FizzBuzz {\n\tpublic static void main(String[] args) {"
                + generateOutputPart()
                + "\n\t}\n}";
        outputFile("FizzBuzz.java", sourceText);
    }

    private static String generateOutputPart() {
        return IntStream.rangeClosed(1, 100)
                .mapToObj(FizzBuzzSourceGenerator::generateFizzBuzzTextOf)
                .map(s -> String.format("\n\t\tSystem.out.print(\"%s \");", s))
                .collect(Collectors.joining());
    }

    private static String generateFizzBuzzTextOf(int number) {
        String result = "";
        if (number % 3 == 0) result += "Fizz";
        if (number % 5 == 0) result += "Buzz";
        return result.length() == 0 ? String.valueOf(number) : result;
    }

    private static void outputFile(String filePath, String text) throws FileNotFoundException {
        try (PrintWriter writer = new PrintWriter(filePath)) {
            writer.println(text);
        }
    }
}