Mega Code Archive
Counts words in a file, outputs results in sorted form
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// : c12:WordCount.java
// Counts words in a file, outputs results in sorted form.
// {Args: WordCount.java}
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.StreamTokenizer;
import java.util.Collection;
import java.util.Iterator;
import java.util.Set;
import java.util.TreeMap;
class Counter {
private int i = 1;
public int read() {
return i;
}
public void increment() {
i++;
}
}
public class WordCount1 {
private static final String usage = "Usage: \nWordCount file\n"
+ "Counts the words in the file and "
+ "outputs results in sorted form.";
private FileReader file;
private StreamTokenizer st;
// A TreeMap keeps keys in sorted order:
private TreeMap counts = new TreeMap();
public WordCount1(String filename) throws FileNotFoundException {
try {
file = new FileReader(filename);
st = new StreamTokenizer(new BufferedReader(file));
st.ordinaryChar('.');
st.ordinaryChar('-');
} catch (FileNotFoundException e) {
throw new RuntimeException(e);
}
}
public void dispose() {
try {
file.close();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
public 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) {
throw new RuntimeException(e);
}
}
public Collection values() {
return counts.values();
}
public Set keySet() {
return counts.keySet();
}
public Counter getCounter(String s) {
return (Counter) counts.get(s);
}
public static void main(String[] args) throws FileNotFoundException {
if (args.length == 0) {
System.out.println(usage);
System.exit(1);
}
WordCount1 wc = new WordCount1(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.dispose();
}
} ///:~
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