Please pay attention to the FILENAME and how to print out the filename that I choose from my computer?

Question

it is a simple question, how to print out the selected file name, thanks.

public class CSVMAX {
public CSVRecord hottestInManyDays() {
//select many csv files from my computer
   DirectoryResource dr = new DirectoryResource();
   CSVRecord largestSoFar = null;
//read every row and implement  the method we just define
   for(File f : dr.selectedFiles()) {
    FileResource fr = new FileResource(f);
    CSVRecord currentRow = hottestHourInFile(fr.getCSVParser());
    if (largestSoFar == null) {
       largestSoFar = currentRow;
    }
    else {
    double currentTemp = Double.parseDouble(currentRow.get("TemperatureF"));
        double largestTemp = Double.parseDouble(largestSoFar.get("TemperatureF"));
        //Check if currentRow’s temperature > largestSoFar’s
    if (currentTemp > largestTemp) {
                //If so update largestSoFar to currentRow
            largestSoFar = currentRow;
    }
   }
}
return largestSoFar;        
}

here I want to print out the file name but I dont know how to do that.

public void testHottestInManyDay () {
    CSVRecord largest = hottestInManyDays();
    System.out.println("hottest temperature on that day was in file " + ***FILENAME*** + largest.get("TemperatureF") +
               " at " + largest.get("TimeEST"));
}
}

Answer 1

Ultimately, it seems that hottestInManyDays() will need to return this information.

Does CSVRecord have a property for that?

Something like this:

CSVRecord currentRow = hottestHourInFile(fr.getCSVParser());
currentRow.setFileName(f.getName());

If not, can such a property be added to it?

Maybe CSVRecord doesn't have that property. But it can be added?:

private String _fileName;

public void setFileName(String fileName) {
    this._fileName = fileName;
}

public String getFileName() {
    return this._fileName;
}

If not, can you create a wrapper class for both pieces of information?

If you can't modify CSVRecord and it doesn't have a place for the information you want, wrap it in a class which does. Something as simple as this:

class CSVWrapper {

    private CSVRecord _csvRecord;
    private String _fileName;

    // getters and setters for the above
    // maybe also a constructor?  make them final?  your call

}

Then return that from hottestInManyDays() instead of a CSVRecord. Something like this:

CSVWrapper csvWrapper = new csvWrapper();
csvWrapper.setCSVRecord(currentRow);
csvWrapper.setFileName(f.getName());

Changing the method signature and return value as needed, of course.

---

However you do it, once it's on the return value from hottestInManyDays() you can use it in the method which consumes that:

CSVWrapper largest = hottestInManyDays();
System.out.println("hottest temperature on that day was in file " + largest.getFileName() + largest.getCSVRecord().get("TemperatureF") +
           " at " + largest.getCSVRecord().get("TimeEST"));

(Note: If the bits at the very end there don't sit right as a Law Of Demeter violation, then feel free to extend the wrapper to include pass-thru operations as needed. Maybe even have it share a common interface with CSVRecord so it can be used as a drop-in replacement for one as needed elsewhere in the system.)