import java.io.*;
import java.net.URL;




| This is a little demo showing how to read text files. It will find files
| that are situated anywhere in the classpath.
|
| Currently, two demo methods are available. Both simply print a text file to the
| terminal. One returns exceptions in case of a problem, the other prints out
| error messages.
|
| @author Michael Kölling
| @version 1.0 (19. Feb 2002)
|
public class FileReader
{    



| Create a file reader
|
public FileReader()
    {
        
    }

    


| Show the contents of the file 'fileName' on standard out (the text terminal).
|
| @param fileName  The name of the file to show
| @throws  IOException if the file could not be opened
|
public void showFile(String fileName)
        throws IOException
    {
        InputStream fstream = openFile(fileName);

        
        
        

        BufferedReader in = new BufferedReader(new InputStreamReader(fstream));

        

        System.out.println("File: " + fileName);
        String line = in.readLine();
        while(line != null) {
            System.out.println(line);
            line = in.readLine();
        }
        System.out.println("<end of file>");
    }
        
    


| Same as 'showfile', but don't throw exceptions. If an error occurs,
| write an error message to the terminal.
|
| @param fileName  The name of the file to show
|
public void checkedShowFile(String fileName)
    {
        try {
            showFile(fileName);
        }
        catch(IOException exc) {
            System.out.println("There was a problem showing this file.");
            System.out.println("The error encountered is:");
            System.out.println(exc);
        }
    }

    


| Open a text file and return a stream to read from that file.
| The file can reside anywhere in the classpath.
|
| @param fileName  The name of the file to open
| @return An open stream to read from the file
| @throws  IOException if the file could not be opened
|
public InputStream openFile(String fileName)
        throws IOException
    {
        if(fileName == null)
            throw new IOException("Cannot open file - filename was null.");
        URL url = getClass().getClassLoader().getResource(fileName);
        if(url == null)
            throw new IOException("File not found: " + fileName);
        return url.openStream();
    }
}