import structure.*;
import com.mw.io.*;
import java.io.*;

// This variation of the WordFreq program takes its input from a text file,
// whose name is provided as the parameter args[0].  Note that the ReadStream
// r is linked to the FileInputStream object istream, which is initialized to
// that file name via args[0].  

public class WordFreqSort
{
    //+implementation
    public static void main(String args[])
    {
    Vector vocab = new Vector(1000);
	int i;
    try {
        InputStream istream = new FileInputStream(args[0]);
     	ReadStream r = new ReadStream(istream);
 
	// for each word on input
	for (r.skipWhite(); !r.eof(); r.skipWhite())
	{
	    Association wordInfo; // word-frequency association
	    String vocabWord;	  // word in the list

	    // read in and tally instance of a word
	    String word = r.readString();
	    for (i = 0; i < vocab.size(); i++)
	    {
		// get the association
		wordInfo = (Association)vocab.elementAt(i);
		// get the word from the association
		vocabWord = (String)wordInfo.key();
		if (vocabWord.equals(word))
		{   // match: increment integer in association
		    Integer f = (Integer)wordInfo.value();
		    wordInfo.setValue(new Integer(f.intValue() + 1));
		    break;
		}
	    }
	    // mismatch: insert new word at position 0, with frequency 1.
	    if (i == vocab.size())
	    {
		vocab.insertElementAt(
		    new Association(word,new Integer(1)), 0);
	    }	    
	}
	} catch (IOException e) {
	   System.err.println(e);
	   return;
	}
	// remove all the elements that occur once
	for (i = 0; i < vocab.size(); i++) {
	    if (((Integer)(((Association)vocab.elementAt(i)).value())).intValue() == 1)
	       vocab.removeElementAt(i);  
	}
	
	// sort vector by frequency
	VectorInsertionSort.insertionSort(vocab, vocab.size());
	
	// print out the accumulated word frequencies
	for (i = 0; i < vocab.size(); i++)
	{
	    Association wordInfo = (Association)vocab.elementAt(i);
	    System.out.println(
 	       wordInfo.key()+" occurs "+
               wordInfo.value()+" times.");
	}
    }
    //-implementation
}