Question

I've previously completed a Java assignment where I wrote a program that reads a given text file and creates an index that stores the line numbers for where individual words occur. I've been given a new assignment where I need to modify some of my old code.

I need to replace the indexer in my Index class with a NavigableMap<String, Word> and update my Word class with NavigableSet<Integer> lines. The instantiated objects should be TreeMap() and TreeSet(). I have below my code for those two classes, a test harness I was provided with, and a sample text file used for the assignment.

INDEXER CLASS

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Indexer
{
  
private List<Word> index;
private String fn;

public Indexer(String filename)
{
this.fn = filename;
index = new ArrayList<Word>();
}

public boolean index()
{
indexfile();
return true;
}

private void lineSplitter(String line, int lineno)
{
String[] words = null;
if (line.length() > 0) {
words = line.split("\\W+");
for (int i = 0; i < words.length; i++) {
boolean flag = false;
Word w = new Word(words[i]);
  
for (int j = 0; j < index.size(); j++) {
if (index.get(j).getWord().equals(w.getWord())) {
w = index.get(j);
w.addLine(lineno);
flag = true;
break;
}
}
  
if (!flag) {
w.addLine(lineno);
index.add(w);
}
}
}
}

private void indexfile()
{
try {
Scanner scan = new Scanner(new File(fn));
int count = 1;
String line;
while (scan.hasNextLine()) {
line = scan.nextLine();
lineSplitter(line, count);
count++;
}
scan.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}

public List find(String w)
{
Word word = null;
for (int j = 0; j < index.size(); j++) {
if (index.get(j).getWord().equals(w)) {
word = index.get(j);
return word.getLines();
}
}
return null;
}

public void dumpList()
{
for (int i = 0; i < index.size(); i++) {
System.out.println(index.get(i).getWord() + " : " + index.get(i).getLines());
}
}
}

WORD CLASS

import java.util.ArrayList;
import java.util.List;

public class Word
{
private String w;
private List<Integer> lines;
  
public Word(String word)
{
this.w = word.toLowerCase();
lines = new ArrayList<Integer>();
}
  
public boolean addLine(int lineno)
{
if(!lines.contains(lineno)){
lines.add(lineno);
}   
return true;
}
  
public String getWord()
{
return w;
}
  
public List getLines()
{
return lines;
}
  
public boolean equals(Object obj)
{
if (this == obj)
return true;

if (obj == null || obj.getClass() != this.getClass())
return false;

Word word = (Word) obj;
return word.w.equals(this.w);
}
}

TEST HARNESS

public class PA5 {

    public static void main(String[] args) {

        Indexer idx = new Indexer(args[0]);

        boolean rc = idx.index();

        idx.dumpList();

   

        System.out.println("*****************");

        List<Integer> x = idx.find("PEACE");

        if ( x!= null)

            System.out.println(x);       

    }

}

SAMPLE TEXT

But soft what light through yonder window breaks
It is the east and Juliet is the sun
Arise fair sun and kill the envious moon
Who is already sick and pale with grief

Answer 1

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Arrays;
import java.util.NavigableMap;
import java.util.NavigableSet;
import java.util.Scanner;
import java.util.TreeMap;
import java.util.TreeSet;

class Indexer {

        private NavigableMap<String, Word> wordMap;
        private String fn;

        public Indexer(String filename) {
                this.fn = filename;
                wordMap = new TreeMap<String, Word>();
        }

        public boolean index() {
                indexfile();
                return true;
        }

        private void lineSplitter(String line, int lineno) {
                String[] words = null;
                if (line.length() > 0) {
                        words = line.split("\\W+");
                        for (int i = 0; i < words.length; i++) {
                                
                                if(!wordMap.containsKey(words[i])) {
                                        wordMap.put(words[i], new Word(words[i]));
                                }
                                
                                wordMap.get(words[i]).addLine(lineno);
                        }
                }
        }

        private void indexfile() {
                try {
                        Scanner scan = new Scanner(new File(fn));
                        int count = 1;
                        String line;
                        while (scan.hasNextLine()) {
                                line = scan.nextLine();
                                lineSplitter(line, count);
                                count++;
                        }
                        scan.close();
                } catch (FileNotFoundException e) {
                        e.printStackTrace();
                }
        }

        public NavigableSet<Integer> find(String w) {
                if(wordMap.containsKey(w)) {
                        return wordMap.get(w).getLines();
                }
                return null;
        }

        public void dumpList() {
                for(String w: wordMap.keySet()) {
                        System.out.println(w + ": " + Arrays.toString(find(w).toArray()));
                }
        }
}

class Word {
        private String w;
        private NavigableSet<Integer> lines;

        public Word(String word) {
                this.w = word.toLowerCase();
                lines = new TreeSet<Integer>();
        }

        public boolean addLine(int lineno) {
                if (!lines.contains(lineno)) {
                        lines.add(lineno);
                }
                return true;
        }

        public String getWord() {
                return w;
        }

        public NavigableSet<Integer> getLines() {
                return lines;
        }

        public boolean equals(Object obj) {
                if (this == obj)
                        return true;

                if (obj == null || obj.getClass() != this.getClass())
                        return false;

                Word word = (Word) obj;
                return word.w.equals(this.w);
        }
}

public class PA5 {

        public static void main(String[] args) {

                Indexer idx = new Indexer(args[0]);

                idx.index();

                idx.dumpList();

                System.out.println("*****************");

                NavigableSet<Integer> x = idx.find("PEACE");

                if (x != null)
                        System.out.println(Arrays.toString(x.toArray()));

        }

}

please upvote.