newcopybytes.java

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import java.io.*; 
class NewCopyBytes{ 
   public static void main ( String[] args ) {  
       DataInputStream  instr;
       DataOutputStream outstr;
       if ( args.length != 2 ) { 
          System.out.println("Please Enter file names!");
          return;
       }
       File inFile  = new File( args[0] );
       File outFile = new File( args[1] );
       if ( outFile.exists() ) { 
           System.out.println( args[1] + " already exists");      
           return;   
       }
       if ( !inFile.exists() )  {
           System.out.println( args[0] + " does not exist");   
           return;   
       }
       try {
           instr = new DataInputStream(new BufferedInputStream(
                                              new FileInputStream( inFile )));
           outstr = new DataOutputStream(new BufferedOutputStream(
                                              new FileOutputStream( outFile  )));
           try {
                int data;
                while ( true ) { 
                    data = instr.readUnsignedByte() ; outstr.writeByte( data ) ;  
                }
            }
            catch ( EOFException  eof ) {
                outstr.close();   
                instr.close();    
                return;     
            }
        }     
        catch ( FileNotFoundException nfx ){  
            System.out.println("Problem opening files" );    
        }
        catch ( IOException iox ){  
            System.out.println("IO Problems" );    
        }
    }
}