initialise object variable from file paths

Question

servername
|-- reports
|    |-- ABC
|    |    |-- COB02May2017
|    |    |    |-- pnlreport.pdf
|    |    |    |-- balancereport.pdf
|    |    |-- COB03May2017
|    |-- CustomerB
|    |    |-- COB02May2017
|    |    |-- COB03May2017
|    |    |    |-- balancereport.pdf 
|    |-- 01CFG
|    |    |-- COB03Sep2017

I have the above directory tree that holds my customer reports.

I have the following ReportDeliverable model:

public class ReportDeliverable {

    private String reportId;
    private String reportName;
    private String customer;
    private String format;
    private Date cobDate;
}

ReportSchedule:

public class ReportSchedule {

    private final String schedule;
    private final String reportId;
    private final String filePattern;
    private final String format;
    private final String filePath;

}

I have the following class which is responsible for providing the list of report deliverable objects:

@Service
public class FileServiceImpl implements FileService {


    @Value("${reports.source-path}")
    private String sourcePath;


    @Override
    public List<ReportDeliverable> getReportDeliverables(ReportSchedule reportSchedule) {
        List<ReportDeliverable> reportDeliverables = new ArrayList<>();
        List<Path> filesToProcess = getFilesToProcess(reportSchedule);

        filesToProcess.forEach(path -> {
            //for each path returned, extract and initialise ReportDeliverable object
            ReportDeliverable reportDeliverable = new ReportDeliverable();
            //reportDeliverable.setReportName(); > pnlreport.xls
            //reportDeliverable.setFormat(); >  > PDF
            //reportDeliverable.setCobDate(); > 26-SEP-2017
            //reportDeliverable.setClient(); > CustomerA
            //reportDeliverable.setFilePath(); > \servername\reports\CustomerA\COB26Sep2017\pnlreport.pdf

            reportDeliverables.add(reportDeliverable); 
        });

        return reportDeliverables;
    }

    public List<Path> getFilesToProcess(ReportSchedule reportSchedule) {

        String pattern = reportSchedule.getFilePattern(); //e.g. pnlreport
        String format = reportSchedule.getFormat(); // PDF

        //return full paths from here based on report criteria for COB that is T-1 (day before today). ignore the rest
        // e.g. if today is 27/09/2017
        //return -> \servername\reports\CustomerA\COB26Sep2017\pnlreport.pdf, \servername\reports\CustomerB\COB26Sep2017\pnlreport.PDF

        return path;
    }
}

Daily a directory is created with name being COB-{prior-day-date} as above directory structure. With Java 8,

1. I need some help returning all the file paths that concern the criteria held in ReportSchedules. I have tried to explain in the comments in getFilesToProcess(ReportSchedule reportSchedule)
2. From the paths, I need to initialize the ReportDeliverable fields, again explained in the comments getReportDeliverables(ReportSchedule reportSchedule)

Answer 1

My understanding of your question is how to recusively go though the directory structure to find files fitting a particular pattern in directories of that are named in a way that includes a formatted date following a particular formatting rule. Here is what I came up with. There are optimizations possible but it should be a starting point.

If I understood your question wrong, you might rephrase it a bit, so I can correct my answer.

import java.io.File;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import java.util.Locale;

public class RetrievePathsOfYesterday {

    public final static void main(String[] args) {
        String pattern = "pnlreport";
        String format = "PDF";
        String baseDir = "F:/Test";
        switch(args.length) {
        case 3:
            format = args[2];
        case 2:
            pattern = args[1];
        case 1:
            baseDir = args[0];
        }
        File root = new File(baseDir);
        File[] customerDirs = root.listFiles(file -> file.getName().toLowerCase(Locale.ENGLISH).startsWith("customer"));
        ArrayList<Path> result = new ArrayList<>();
        for (int i = 0; i < customerDirs.length; i++) {
            result.addAll(getFilesToProcess(customerDirs[i], pattern, format));
        }
        System.out.println(result);
    }

    public static List<Path> getFilesToProcess(File baseDir, String pattern, String format) {
        pattern = pattern.toLowerCase(Locale.ENGLISH);
        format = "." + format.toLowerCase(Locale.ENGLISH);
        Calendar now = Calendar.getInstance();
        now.add(Calendar.DAY_OF_YEAR, -1);
        SimpleDateFormat sdf = new SimpleDateFormat("ddMMMyyyy", Locale.ENGLISH);
        File startDir = new File(baseDir, "COB" + sdf.format(now.getTime()));
        ArrayList<Path> result = new ArrayList<>();
        getFilesToProcess(result, startDir, pattern, format);
        return result;
    }

    private static void getFilesToProcess(List<Path> resList, File baseDir, String pattern, String format) {
        System.out.println("processing " + baseDir.getAbsolutePath());
        if (!baseDir.exists()) {
            return;
        }
        File[] files = baseDir.listFiles(pathName -> {
            System.out.println("filter " + pathName.getName());
            if (pathName.isDirectory()) {
                return true;
            }
            if (!pathName.isFile()) {
                return false;
            }
            String name = pathName.getName().toLowerCase(Locale.ENGLISH);
            if (!name.startsWith(pattern)) {
                return false;
            }
            if (!name.endsWith(format)) {
                return false;
            }
            return true;
        });

        for (int i = 0; i < files.length; i++) {
            File current = files[i];
            System.out.println("Checking " + current.getAbsolutePath());
            if (current.isDirectory()) {
                getFilesToProcess(resList, current, pattern, format);
                continue;
            }
            resList.add(Paths.get(current.toURI()));
        }
    }
}

I tested this code with the following directory structure:

kimmerin@harry /cygdrive/f
$ ls -R Test
Test:
CustomerA  CustomerB

Test/CustomerA:
COB26Sep2017

Test/CustomerA/COB26Sep2017:
pnlreport.pdf

Test/CustomerB:
COB26Sep2017

Test/CustomerB/COB26Sep2017:
otherreport.PDF

If you replace Test with servername/report this should be exactly like the structure you described in your question. This is the output when starting the class with the default values:

filter pnlreport.pdf

Checking F:\Test\CustomerA\COB26Sep2017\pnlreport.pdf

processing F:\Test\CustomerB\COB26Sep2017

filter otherreport.PDF

[F:\Test\CustomerA\COB26Sep2017\pnlreport.pdf]