// COM3336 Operating Systems
// Homework 2 part 1
// John Sung
// Started: 10/22/1999
//


import java.util.*;
import java.io.*;


// the File abstract class that defines an interface to all of the different
// objects within this file system.
public abstract class File
{

	 //////////////////////////////////////////////////////////////
	 // Private Data Members

	 // The name of this File
	 private String FileName;

	 
	 //////////////////////////////////////////////////////////////
	 // methods that everyone will inherit

	 
	 // the default constructor
	 public File(String fileName)
	 {
		  FileName = fileName;
	 }


	 // get the filename
	 public String getFileName()
	 {
		  return FileName;
	 }


	 //////////////////////////////////////////////////////////////
	 // Abstract methods in which everyone must
	 // implement in each of the "subfiles"


	 // a function to recursively copy a File, with a file
	 // as the parent of the copy. Parent, only useful for coping
	 // directories.
	 public abstract File recursiveCopy(File Parent);

	 // function to find a particular file and print it to an
	 // ostream
	 public void recursiveFindAndPrint(String prefix,
												  String fileName,
												  PrintStream out)
	 {
		  // if the 2 filenames are same, then print
		  // the full path to this file
		  if (getFileName().compareTo(fileName)==0)
				out.println(prefix + "/" + fileName);
	 }
	 

	 // function to implement the "du ." command. The object that
	 // implements this function sould print itself if it's
	 // a directory to the ostream.
	 public abstract void recursivePrintDirectory(String prefix,
																 PrintStream out);
	 
	 // function to implement the "du -a" command. The object that
	 // implements this function sould print itself to the ostream.
	 public void recursivePrintAll(String prefix,
											 PrintStream out)
	 {
		  // print myself
		  out.println(prefix + "/" +getFileName());	  
	 }
	 
	 
	 // function to implement the directory down command,
	 // returns null if something goes wrong.
	 public abstract File changeDirectory(String subDirName,
														PrintStream err);

	 // function returns the parent, unless it doesn't have a
	 // parent. Used to implement cd ..
	 public abstract File getParent();

	 // function used to implement the touch command.
	 // it attempts to create a file. Outputs any errors
	 // to err.
	 public abstract void createFile(String newFileName,
												PrintStream err);

	 // function used to implement the mkdir command.
	 // it attempts to create a directory. Outputs any errors
	 // to err.
	 public abstract void createDir(String newDirName,
											  PrintStream err);
	 

	 // function used to implement rmdir. Outputs error to
	 // the err PrintStream if something goes wrong.
	 public abstract boolean removeDir(String dirName,
												  PrintStream err);
	 
	 // function used to implement rm. Outputs error to
	 // the err PrintStream if something goes wrong.
	 public abstract boolean removeFile(String fileName,
													PrintStream err);
	 
	 
}