//  Search.java  (c) 2005 Kari Laitinen

//  http://www.naturalprogramming.com

//  2004-10-08  File created.
//  2005-11-19  Last modification.

//  The best way to execute this program is to run it in a
//  command prompt window where command line parameters can
//  be given. It may be difficult, and even impossible, to
//  supply the command line parameters if this program is 
//  executed with a modern development tool such as JCreator
//  or Eclipse.

//  This program will, though, ask for data from the user
//  if no command line parameters are given.

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

class Search
{
   static void search_string_in_file( String  file_name_from_caller,
                                      String  string_to_be_searched )
   {
      try
      {
         BufferedReader file_to_read  =
             new BufferedReader( new FileReader( file_name_from_caller ) ) ;

         System.out.print( "\n Searching ... \""
                        +  string_to_be_searched  + "\"\n" ) ;

         int  line_counter  =  0 ;
         boolean  end_of_file_encountered  =  false ;

         while ( end_of_file_encountered  ==  false )
         {
            String  text_line_from_file   =  file_to_read.readLine() ;

            if ( text_line_from_file  ==  null )
            {
               end_of_file_encountered  =  true ;
            }
            else
            {
               line_counter  ++ ;

               if ( text_line_from_file.contains( string_to_be_searched ) )
               {
                  System.out.print( "\n String \"" +  string_to_be_searched
                               + "\" was found on line "  +  line_counter ) ;
               }
            }
         }

         file_to_read.close() ;
      }
      catch ( FileNotFoundException caught_file_not_found_exception )
      {
         System.out.print( "\n Cannot open \"" + file_name_from_caller + "\"");
      }
      catch ( IOException caught_io_exception )
      {
         System.out.print( "\n\n  File processing error.  \n" ) ;
      }
   }


   public static void main( String[] command_line_parameters )
   {
      Scanner keyboard = new Scanner( System.in ) ;

      if ( command_line_parameters.length  ==  2 )
      {
         search_string_in_file ( command_line_parameters[ 0 ],
                                 command_line_parameters[ 1 ] ) ;
      }
      else
      {
         System.out.print( "\n This program can search a string in a "
                         + "\n text file. Give first the file name :  " ) ;

         String  file_name_given_by_user  =  keyboard.nextLine() ;

         System.out.print( "\n Type in the string to be searched: " ) ;

         String  string_to_be_searched    =  keyboard.nextLine() ;

         search_string_in_file( file_name_given_by_user,
                                string_to_be_searched ) ;
      }
   }
}