Java Program- File & Directories

Question

Hi, I was wondering if anyone can helpe me out with this program. I have a good start on it but keep on getting errors.
The task is to read one command line argument that contains the directory name. Using recursion, traverse the directory and all its sub-directories. Then for each file in each direcotry create an object class which keeps track of the file name (absolute path) and the size of the file, then adds the object to a Vector. Once thats done, i have to print a report showing each file name and size in decending order of file size. I have attached what i have so far... if ne one can help me i'll be verryyyyy greatfulll
for(i=0; i<fileList.size(); i++){
File file = (File)fileList.get(i);
System.out.print(file.getAbsolutePath());
System.out.println("Length of File: " + file.length());

Answer 1

Hi,
First you have to recursive method to build your file List and then sort the list and print. You can get a good start from the following code:
public void buildFileList(File file, ArrayList list)
    list.add(file);
    if(file.isDirectory())
      File[] files = file.listFiles();
      for(int i=0; i < files.length; i++)
        buildFileList(files, list);
public void printFiles(ArrayList list)
Comparator cmp = new Comparator()
public int compare(Object o1, Object o2)
if( ((File)o1).length() > ((File)o2).length() )
return -1;
else if( ((File)o1).length() < ((File)o2).length() )
return 1;
else
return 0;
Collections.sort(list);
for(int i=0; i < list.size(); i++)
System.out.println(((File)list.get(i)).getAbsolutePath());