package test.io;
 
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.BufferedWriter;
import java.io.PrintWriter;
import java.io.FileWriter;
 
import java.io.IOException;
 
import org.apache.log4j.Category;
import org.apache.log4j.BasicConfigurator;
/**
  * This code is free of any copyrights (not even GPL).
  * 
  * It would just be nice if you could mention the author as follow :
  * @author <a href="mailto:tsmets@altern.org">Thomas SMETS</a>, Copyright Free.
  *
  *
  *
  */
public class ReadingLineAndProcessing
{
  public static Category log = Category.getInstance (ReadingLineAndProcessing.class);
  public static final String USAGE 
    = "java test.io.ReadingLineAndProcessing <aFileNameToProcess>";  
  public static final String PROPERTY_LINE_SEPARATOR = "line.separator";
  public static final String LINE_SEPARATOR = System.getProperty (PROPERTY_LINE_SEPARATOR);
  public static final String TEMP = "Temp_";
  
 
  public static void main (String[] args)  
    throws Exception
  {
    BasicConfigurator.resetConfiguration ();
    BasicConfigurator.configure ();
    
    if (args.length < 1)
      printUsage ();
    
    BufferedReader in = new BufferedReader(new FileReader( args[0] ));
    PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter(TEMP + args[0])));
    
    String S, pS;
    while ((S = in.readLine ()) != null )
    {
      log.info ("Reading a line : " + S);
      pS = processString (S);
      out.write (pS);
      out.write (LINE_SEPARATOR);
    }  
    
    out.flush ();
    out.close ();
    in.close ();
    
    log.info ("Re-copying");
    
    in = new BufferedReader(new FileReader(TEMP + args[0] ));
    out = new PrintWriter(new BufferedWriter(new FileWriter(args[0])));
    
    while ((S = in.readLine ()) != null )
    {     
      out.write (S);
      out.write (LINE_SEPARATOR);
    }
        
    out.flush ();
    out.close ();
    in.close ();
    
    log.info ("Copied ...");
  }
  
  public static String processString (String s)
  {
    String processedS;        
    return processedS = s + s;
  }
  
  public static void printUsage ()
  {
    System.out.println (USAGE);
  }
}

import java.io.*;
 
import org.apache.log4j.Category;
import org.apache.log4j.BasicConfigurator;
 
/**
  * This code is free of any copyrights (not even GPL).
  * 
  * It would just be nice if you could mention the author as follow :
  * @author <a href="mailto:tsmets@altern.org">Thomas SMETS</a>, Copyright Free.
  *
  */
public class TestFileReader
{
  public static final int BUFFER_SIZE = 4096;
  public static final int ERR = 1;
  public static final int EOF = -1;
  public static final int FILE_ENDED = 0;
  
  public static final String ENCODING = "US-ASCII"; 
  public static final String USAGE 
  
    = "Usage :\njava TestFileReader <file_source> <file_destination>\n\n That's it ...\n";
 
  public static Category log = null;
 
/** 
  * The entry point
  */
  public static void main (String[] args)
  {
    BasicConfigurator.resetConfiguration ();
    BasicConfigurator.configure (); 
    log = Category.getInstance (TestFileReader.class);   
    
    if (args.length != 2)
    {
      usage();
      System.exit (ERR);
    }
    
    try
    {
      
      DataInputStream in = new DataInputStream(new FileInputStream(args[0]));      
      DataOutputStream out = new DataOutputStream (new FileOutputStream(args[1]));
      int read;
      byte[] b;
      while (( read = in.available ()) != FILE_ENDED)
      {
        b = new byte[read];
        in.read (b);
        out.write (b);
        
      }
      
      out.flush ();
      out.close ();
      in.close ();
      
      
      log.info ("File writer / Reader closed");
      
      if (check(args[0], args[1]))
        log.info ("Copy : OK");
      else 
        log.warn ("Copy : NOK");
        
    }catch(Exception e)
    {
      log.fatal ("Exception :" + e.getClass ().getName ());
      log.fatal ("Message :" + e.getMessage () );
      usage ();
    }  
  }
  
  
  public static void usage ()
  {
    log.error (USAGE);
  }
  
  public static boolean check(String srcFileName, String destFileName)
  {
    try 
    {
      log.info ("Checking ...");
      DataInputStream srcData 
        = new DataInputStream (new FileInputStream (srcFileName));
      DataInputStream destData 
        = new DataInputStream (new FileInputStream (destFileName));
      
      BufferedInputStream srcBIS = new BufferedInputStream (srcData);
      BufferedInputStream destBIS = new BufferedInputStream (destData);            
      log.info ("Stream created");      
      
      StringBuffer srcBuf = new StringBuffer(), destBuf = new StringBuffer ();
      String s = null;
      int read = 0;
      byte [] b;
      while ((read = srcBIS.available ()) != FILE_ENDED)
      {
        b = new byte [read];
        srcBIS.read (b);        
        srcBuf.append ( new String (b, ENCODING ));
        log.info ("Reading " + read + " bytes");
      }
      
      read = 0;
      while (( read = destBIS.available ()) != FILE_ENDED)
      {        
        b = new byte [read];
        destBIS.read (b);
        destBuf.append ( new String (b, ENCODING) );
        log.info ("Reading " + read + " bytes");
      } //       
            
      if (destBuf.toString ().equals (srcBuf.toString ()))
        return true;
      else 
        return false;        
    }    
    catch (Exception ex) 
    {
      log.warn ("Exception " + ex);
      return false;
    }        
  }  
}