Java – generate a large stream for testing

We have a web service. We upload files and want to write an integration test to upload a slightly larger file The test process needs to generate files (I don't want to add larger files to source code control)

I want to generate a stream of about 50 MB to upload The data itself is not important I tried this with an object in memory, which was easy, but I ran out of memory

Integration tests are written in groovy, so we can generate data using groovy or Java APIs How do we generate a random stream to upload instead of always saving it in memory?

Solution

This is a simple program that generates a 50 MB text file with random content

import java.io.PrintWriter;
import java.util.Random;


public class Test004 {

    public static void main(String[] args) throws Exception {
        PrintWriter pw = new PrintWriter("c:/test123.txt");
        Random rnd = new Random();
        for (int i=0; i<50*1024*1024; i++){
            pw.write('a' + rnd.nextInt(10));
        }
        pw.flush();
        pw.close();
    }

}