navigate directory structure and name each processed file uniquely

Question

I have a directory structure of the form start/one/two/three/*files*

My goal is to construct this program such that it can navigate my directory structure autonomously, grab each file then process it, which it seems to be doing correctly.

BUT I also need the output to be written to a new file with a unique name, i.e. the file named 00001.txt should be processed and the results should be written to 00001_output.txt

I thought I implemented that correctly but, apparently not.

Where have I gone astray?

    String dirStart = "/home/data/";

    Path root = Paths.get(dirStart);

    Files.walkFileTree(root.toAbsolutePath().normalize(), new SimpleFileVisitor<Path>() 
    {
        @Override
        public FileVisitResult visitFile(Path file, java.nio.file.attribute.BasicFileAttributes attrs) throws IOException 
        {


            try(InputStream inputStream = Files.newInputStream(file);
                    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream)))
            {

                // CHANGE OUTPUT TO NEW FILE
                String print_file = file.getFileName().toString();
                String fileNameWithOutExt = FilenameUtils.removeExtension(print_file);
                System.out.println(fileNameWithOutExt);

                PrintStream out = new PrintStream(new FileOutputStream( fileNameWithOutExt + "_output.txt" ) );
                System.setOut(out);


                // SOUP PART
                StringBuilder sb = new StringBuilder();
                String line = bufferedReader.readLine();

                while (line != null) 
                {

                    sb.append(line);
                    sb.append(System.lineSeparator());
                    line = bufferedReader.readLine();
                }
                String everything = sb.toString();


                Document doc = Jsoup.parse(everything);
                String link = doc.select("block.full_text").text();
                System.out.println(link);


            } 
            catch (IOException e) 
            {
                e.printStackTrace();
            }

            return FileVisitResult.CONTINUE;
        }
    }); 

This is also my question, it might give some additional insight on what I'm actually trying to do.

Answer 1

System.setOut seems like a bad idea.

Below is some untested code which might work.

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.nio.charset.StandardCharsets;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.SimpleFileVisitor;
import org.apache.commons.io.FilenameUtils;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;

public class App {

    public static void main(String[] args) throws IOException {
        String dirStart = "/home/data/";

        Path root = Paths.get(dirStart);

        Files.walkFileTree(root.toAbsolutePath().normalize(), new SimpleFileVisitor<Path>() {
            @Override
            public FileVisitResult visitFile(Path file, java.nio.file.attribute.BasicFileAttributes attrs) throws IOException {

                // CHANGE OUTPUT TO NEW FILE
                String print_file = file.getFileName().toString();
                String fileNameWithOutExt = FilenameUtils.removeExtension(print_file);
                System.out.println(fileNameWithOutExt);

                // SOUP PART
                String everything = new String(Files.readAllBytes(file), StandardCharsets.UTF_8);

                Document doc = Jsoup.parse(everything);
                String link = doc.select("block.full_text").text();

                try (PrintStream out = new PrintStream(new FileOutputStream(fileNameWithOutExt + "_output.txt"))) {
                    out.println(link);
                } catch (IOException e) {
                    e.printStackTrace();
                }

                return FileVisitResult.CONTINUE;
            }
        });
    }

}