Word Count : File Commands « File Input Output « Java

Word Count

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Map;
import java.util.StringTokenizer;

public class WordCount {
  static final Integer ONE = new Integer(1);

  public static void main(String args[]) throws IOException {

    Hashtable map = new Hashtable();
    FileReader fr = new FileReader(args[0]);
    BufferedReader br = new BufferedReader(fr);
    String line;
    while ((line = br.readLine()) != null) {
      processLine(line, map);
    Enumeration e = map.keys();
    while (e.hasMoreElements()) {
      String key = (String) e.nextElement();
      System.out.println(key + " : " + map.get(key));

  static void processLine(String line, Map map) {
    StringTokenizer st = new StringTokenizer(line);
    while (st.hasMoreTokens()) {
      addWord(map, st.nextToken());

  static void addWord(Map map, String word) {
    Object obj = map.get(word);
    if (obj == null) {
      map.put(word, ONE);
    } else {
      int i = ((Integer) obj).intValue() + 1;
      map.put(word, new Integer(i));


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