Question

Reading and Writing Files in a Directory

Create a program that provides a listing of all the files in a directory. The program should be a Java application that accepts a single argument into the args array of the main() method. This argument identifies the name of a directory. The application should make sure that this filename really does identify a directory and then list all of the files in the directory. For each file, list whether the file is a file or a directory and list the size for each file. The program should print its output to System.out.

Answer 1

Thanks for the question.

Here is the completed code for this problem.  Let me know if you have any doubts or if you need anything to change.

Thank You !!

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public class DirectoryListing {

    public static void main(String[] args) {

        if(args.length==0){
            System.out.println("Please enter the directory as command line argument.");
            System.exit(0);
        }
        String directoryPath=args[0];
        File folder = new File(directoryPath);
        if(folder.isDirectory()){

            File[] listOfFiles = folder.listFiles();
            for (int i = 0; i < listOfFiles.length; i++) {
                if (listOfFiles[i].isFile()) {
                    System.out.println("File : " + listOfFiles[i].getName()+" File Size: "+listOfFiles[i].length()+" bytes");
                } else if (listOfFiles[i].isDirectory()) {
                    System.out.println("Directory : " + listOfFiles[i].getName());
                }
            }

        }else{
            System.out.println(directoryPath+" is not a directory");
        }

    }
}

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