//: c11:WordCount.java // From 'Thinking in Java, 2nd ed.' by Bruce Eckel // www.BruceEckel.com. See copyright notice in CopyRight.txt. // Counts words from a file, outputs // results in sorted form. import java.io.*; import java.util.*; class Counter { private int i = 1; int read() { return i; } void increment() { i++; } } public class WordCount { private FileReader file; private StreamTokenizer st; // A TreeMap keeps keys in sorted order: private TreeMap counts = new TreeMap(); WordCount(String filename) throws FileNotFoundException { try { file = new FileReader(filename); st = new StreamTokenizer( new BufferedReader(file)); st.ordinaryChar('.'); st.ordinaryChar('-'); } catch(FileNotFoundException e) { System.err.println( "Could not open " + filename); throw e; } } void cleanup() { try { file.close(); } catch(IOException e) { System.err.println( "file.close() unsuccessful"); } } void countWords() { try { while(st.nextToken() != StreamTokenizer.TT_EOF) { String s; switch(st.ttype) { case StreamTokenizer.TT_EOL: s = new String("EOL"); break; case StreamTokenizer.TT_NUMBER: s = Double.toString(st.nval); break; case StreamTokenizer.TT_WORD: s = st.sval; // Already a String break; default: // single character in ttype s = String.valueOf((char)st.ttype); } if(counts.containsKey(s)) ((Counter)counts.get(s)).increment(); else counts.put(s, new Counter()); } } catch(IOException e) { System.err.println( "st.nextToken() unsuccessful"); } } Collection values() { return counts.values(); } Set keySet() { return counts.keySet(); } Counter getCounter(String s) { return (Counter)counts.get(s); } public static void main(String[] args) throws FileNotFoundException { WordCount wc = new WordCount(args[0]); wc.countWords(); Iterator keys = wc.keySet().iterator(); while(keys.hasNext()) { String key = (String)keys.next(); System.out.println(key + ": " + wc.getCounter(key).read()); } wc.cleanup(); } } ///:~