Converting a println out in to a method

[gcclinux]

I have a class that returns a result to command line using println (list);

THIS IS THE RESULT WHEN I RUN THE FIRST CLASS

C:\>java -cp Details.jar packages.ListFiles
C:\temp\bkdb.txt
C:\temp\nbu6.5.6\BitmapImage.bmp
C:\temp\nbu6.5.6\Something.txt
C:\temp\New Bitmap Image.bmp
C:\temp\New Text Document.txt

public static void main(String[] args) throws FileNotFoundException {
    // USING java.io.File
    File folder = new File("C:/temp");
    // USING java.util.List
      List<File> contents = ListFiles1.getFileListing(folder);


      // PRINT OUT THE LIST OF FILES


        for (File list : contents) {
            if (list.isFile() && list.getName().toLowerCase().endsWith(".txt")
                 || list.getName().toLowerCase().endsWith(".bmp")
                 || list.getName().toLowerCase().endsWith(".doc")
        )
         System.out.println(list);
        }
}

So I have aquestion then, can I take this code I have with a for loop on specific files and convert that to a method so that the second class can access it?

Many Thanks

[KevinWorkman]

You sure can. What happened when you tried?

[gcclinux]

I keep getting "cannot return a value from a method whose result type is void" but I don't know how to do otherwise. This bit of code above has taken me weeks to figure out and getting it to work as I am still learning to program java, so everything is very slow to figure it out but that is part of learning and I learn from examples :)

[DarrylBurke]

Returning a Value from a Method (The Java™ Tutorials > Learning the Java Language > Classes and Objects)

db

[gcclinux]

Hi Darryl.Burke I had found that page via serching google, I unerstand what void doesn't return a value. and that is my problem as for me to capture the output and pass it on the the second class it can not be void, but I can not figure out how to change the first class to give me the same result unless I use void... catch 22

I know I need to read allot of documentation and I have been doing so but things don't always make sense.

Weel thanks for the link anyway.

[Tolls]

So what do you want to return?
How are you calling this?
Presumably the main() method?
What are you requirements?

[gcclinux]

Hi Tolls, well I know that I need change it so that instead of pronting the files to the console, it builds a List of the file and returns it so that I can then create a second class and call the first class to get the result (list of file names)

Does that make sense? Thanks for trying to help.

[ozzyman]

    // USING java.io.File
    File folder = new File("C:/temp");
    // USING java.util.List
      List<File> contents = ListFiles1.getFileListing(folder);


      // PRINT OUT THE LIST OF FILES


        for (File list : contents) {
            if (list.isFile() && list.getName().toLowerCase().endsWith(".txt")
                 || list.getName().toLowerCase().endsWith(".bmp")
                 || list.getName().toLowerCase().endsWith(".doc")
        )
         System.out.println(list);
        }

take all of it out of the main method, do something like this:

public static void main(String[] args) {
    String output = getFileList().toString();
    System.out.println(output);
}

public static List<File> getFileList() {
    //your code
    return contents;
}

then from your other class you can get the same list:
firstClass.getFileList()

[Tolls]

Essentially what ozzyman says, but you'll have to change what happens in your loop, building up a second List that will be what you return, rather than the contents List.

[gcclinux]

You guys are great, thank you for your help I managed to get it to work just like I wanted, I did change the code and moved the for loop with file extentions to the second class :)

import java.io.File;
import java.io.FileNotFoundException;
import java.util.List;

public class ShowFiles {
 public static void main(String[] args) throws FileNotFoundException {

    List<File> listFiles = ScanFiles.getFileList();

    for (File aList : listFiles) {

            if (aList.isFile() && aList.getName().toLowerCase().endsWith(".txt")
                 || aList.getName().toLowerCase().endsWith(".bmp")
                 || aList.getName().toLowerCase().endsWith(".doc"))

    System.out.println(aList);
     }
  }
}