Your task for this assignment is to complete a Java program that simulates the autocomplete feature that is found on many Web sites and computing devices (such as cell phones). Autocomplete is a feature in which an application predicts the most likely completion(s) of a word or phrase as a user begins to type it. Autocomplete usually runs in real-time, and therefore efficiency is essential. The first screenshot below show Yahoos autocomplete feature at work. I have just typed autoc. The second screenshot shows the autocomplete feature on a typical cell phone. For this assignment, your autocomplete program should work as follows: 1. The user types the beginning of a word (or perhaps a whole word) 2. The program prints the three most likely completions of what the user typed

package hw4;

import java.util.Scanner;

import java.util.SortedSet;

import java.util.TreeSet;

public class HW4Main {

public static void main(String[ ] args) {

Wiktionary wik = new Wiktionary("wiktionary.txt");

System.out.println(wik.getSize());

while (true) {

Scanner console = new Scanner(System.in);

System.out.println("Type part of a word. Type 'q' to stop");

String prefix = console.next();

if (prefix.equals("q")) return;

String[] best = wik.bestNMatches(prefix, 3);

for (String word : best)

System.out.print(word + " ");

System.out.println();

}

}

}

package hw4;

import java.util.Random;

import java.util.SortedSet;

import java.util.TreeSet;

public class Subset {

public static void main(String[] args) {

Random r = new Random();

TreeSet set = new TreeSet();

for (int i=0; i<100; i++)

set.add(r.nextDouble());

SortedSet sub = set.subSet(.4, .6);

System.out.println(sub.size());

for (Double number : sub)

System.out.print(number + " ");

System.out.println();

}

}

package hw4;

import java.io.BufferedReader;

import java.io.FileNotFoundException;

import java.io.FileReader;

import java.io.IOException;

import java.util.Comparator;

import java.util.Iterator;

import java.util.NavigableSet;

import java.util.Scanner;

import java.util.Set;

import java.util.SortedSet;

import java.util.TreeSet;

public class Wiktionary {

private class Entry {

private String word;

private long count;

public Entry(String w, long c) {

word = w;

count = c;

}

public String getWord() { return word; }

public long getCount() { return count; }

public Entry(String entry) {

String parts[] = entry.split("\t");

word = parts[1].trim();

count = new Long(parts[0].trim());

}

public String toString() {

return "(" + word + "," + count + ")";

}

}

private TreeSet entries;

public int getSize() { return entries.size(); }

public Wiktionary(String wiktionaryFile) {

BufferedReader rdr=null;

String line="";

try {

rdr = new BufferedReader(new FileReader(wiktionaryFile));

}

catch (FileNotFoundException e) {

System.out.println("Wiktionary file " + wiktionaryFile + " + not found");

System.exit(0);

}

entries = new TreeSet(wordComparator());

while (true) {

try {

line = rdr.readLine();

}

catch (IOException e) {

System.out.println("IO exception");

System.exit(0);

}

if (line == null) break;

entries.add(new Entry(line));

}

System.out.println(entries.size() + " entries");

// this tree will sort Entries by their counts

TreeSet candidates = new TreeSet(countComparator());

for (Entry sub : entries)

candidates.add(sub);

}

// you will want to re-write this. Currently,

// it just returns up to the first n words produced

// by the iterator for the TreeSet object

// called "entries".

public String[] bestNMatches(String pre, int n) {

String[] best = new String[1];

best[0] = pre;

return best;

}

// compare Entry objects by their words

private static Comparator wordComparator() {

return new Comparator() {

public int compare(Entry e1, Entry e2) {

return -1;

}

};

}

// compare Entry objects by their frequencies

private static Comparator countComparator() {

return new Comparator() {

public int compare(Entry e1, Entry e2) {

return -1;

}

};

}

// if you don't successfully complete the bestNMatches method,

// you can try this one, which should return just a single

// word, representing the most frequently used completion

// of the prefix.

public String bestMatch(String pre) {

return "abc";

}

}