lz77

/*
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package AppPack;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

/**
 *
 * @author Sara
 */
public class LZ77 {
//Compress method that take string data to work on, and returns a list of tags as a result of Compressing this data
   public List<LZ77Tupel> compress( String text )
        {
                //Create a list of typy "LZ77Tupel"
                List<LZ77Tupel> list = new ArrayList<LZ77Tupel>();
                //search variable to contain the history characters that occurs for the first time
                String search = "";
                // input variable now = the content of the text variable.
                //Remember that text variable contain the data to be compressed
                String input = text;
                // next variable works as a pointer that points to the next character in the buffer
                String next;
                int indexGood = 0;
                int indexFound;
                int searchLen;
                // while there is a data in the look ahead buffer keep compressing
                while ( input.length() > 0 )
                {
                        searchLen = 1;
                        // get the first character in the buffer using substring function
                        next = input.substring( 0, searchLen );
                        // check if the character is in your search history or not
                        // in other words check if this is the first time that character happens or not
                        if ( search.indexOf( next ) == -1 )
                        {
                            // Insert the tag values in the list
                                list.add( new LZ77Tupel(0,0, next ) );
                                System.out.println("tag "+"<0,"+"0,"+next+">");
                                // add characters in your search history
                                search += next;
                                System.out.println("This is search history:  "+search);
                                // Remove the current character from you input data
                                //Because you have finished using it
                                input = input.substring( searchLen );
                              // Continue to go back at the start of the while loop
                                //dont continue in the do-while loop
                                continue;
                        }
                        // When the last if condition is wrong
                        //This means that the character you points to now is exist in your search history and used before
                        //Go Inside Do-While loop
                        do
                        {
                                next = input.substring( 0, searchLen );
                                System.out.println("The current character now is: "+next);
                                // Return the index of the current character  from the search history
                                indexFound = search.indexOf( next );
                                System.out.println("the Current character"+next +"Was fount at position "+indexFound+"in the search history");
                                if ( indexFound != -1 )
                                        indexGood = indexFound;
                                // increase the search length by 1;
                                searchLen++;
                                System.out.println("search length now "+searchLen);
                        }
                        while ( indexFound != -1 );
                        // Add the new characters in the search history
                        search += next.substring( 0, next.length() );
                        System.out.println("This is search history: "+search);
                        // Remove the used characters from the input data.
                        input = input.substring( next.length() );
                        list.add( new LZ77Tupel( indexGood, next.length() - 1, next.substring( next.length() - 1 ) ) );
                       System.out.println("tag < "+indexGood+","+(next.length()- 1)+","+next.substring(( next.length()- 1))+">");
                }
                // Return the List of tags
                return list;

        }

    public static void main(String[] args) throws FileNotFoundException, IOException {
                LZ77 lz77 = new LZ77();

                List<LZ77Tupel> list1 = lz77.compress( "abcaaabacaaaa" );

                System.out.println( "Compressed1: " + list1.size() + " tupels." );

    }
}