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Java Source | 2000-05-25 | 4.9 KB | 145 lines |
- //: SortedWordCount.java
- //////////////////////////////////////////////////
- // Copyright (c) Bruce Eckel, 1998
- // Source code file from the book "Thinking in Java"
- // All rights reserved EXCEPT as allowed by the
- // following statements: You can freely use this file
- // for your own work (personal or commercial),
- // including modifications and distribution in
- // executable form only. Permission is granted to use
- // this file in classroom situations, including its
- // use in presentation materials, as long as the book
- // "Thinking in Java" is cited as the source.
- // Except in classroom situations, you cannot copy
- // and distribute this code; instead, the sole
- // distribution point is http://www.BruceEckel.com
- // (and official mirror sites) where it is
- // freely available. You cannot remove this
- // copyright and notice. You cannot distribute
- // modified versions of the source code in this
- // package. You cannot use this file in printed
- // media without the express permission of the
- // author. Bruce Eckel makes no representation about
- // the suitability of this software for any purpose.
- // It is provided "as is" without express or implied
- // warranty of any kind, including any implied
- // warranty of merchantability, fitness for a
- // particular purpose or non-infringement. The entire
- // risk as to the quality and performance of the
- // software is with you. Bruce Eckel and the
- // publisher shall not be liable for any damages
- // suffered by you or any third party as a result of
- // using or distributing software. In no event will
- // Bruce Eckel or the publisher be liable for any
- // lost revenue, profit, or data, or for direct,
- // indirect, special, consequential, incidental, or
- // punitive damages, however caused and regardless of
- // the theory of liability, arising out of the use of
- // or inability to use software, even if Bruce Eckel
- // and the publisher have been advised of the
- // possibility of such damages. Should the software
- // prove defective, you assume the cost of all
- // necessary servicing, repair, or correction. If you
- // think you've found an error, please email all
- // modified files with clearly commented changes to:
- // Bruce@EckelObjects.com. (Please use the same
- // address for non-code errors found in the book.)
- /////////////////////////////////////////////////
-
- // Counts words in a file, outputs
- // results in sorted form.
- import java.io.*;
- import java.util.*;
- import c08.*; // Contains StrSortVector
-
- class Counter {
- private int i = 1;
- int read() { return i; }
- void increment() { i++; }
- }
-
- public class SortedWordCount {
- private FileInputStream file;
- private StreamTokenizer st;
- private Hashtable counts = new Hashtable();
- SortedWordCount(String filename)
- throws FileNotFoundException {
- try {
- file = new FileInputStream(filename);
- st = new StreamTokenizer(file);
- st.ordinaryChar('.');
- st.ordinaryChar('-');
- } catch(FileNotFoundException e) {
- System.out.println(
- "Could not open " + filename);
- throw e;
- }
- }
- void cleanup() {
- try {
- file.close();
- } catch(IOException e) {
- System.out.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.out.println(
- "st.nextToken() unsuccessful");
- }
- }
- Enumeration values() {
- return counts.elements();
- }
- Enumeration keys() { return counts.keys(); }
- Counter getCounter(String s) {
- return (Counter)counts.get(s);
- }
- Enumeration sortedKeys() {
- Enumeration e = counts.keys();
- StrSortVector sv = new StrSortVector();
- while(e.hasMoreElements())
- sv.addElement((String)e.nextElement());
- // This call forces a sort:
- return sv.elements();
- }
- public static void main(String[] args) {
- try {
- SortedWordCount wc =
- new SortedWordCount(args[0]);
- wc.countWords();
- Enumeration keys = wc.sortedKeys();
- while(keys.hasMoreElements()) {
- String key = (String)keys.nextElement();
- System.out.println(key + ": "
- + wc.getCounter(key).read());
- }
- wc.cleanup();
- } catch(Exception e) {
- e.printStackTrace();
- }
- }
- } ///:~