public void run() {
// each file is processed into a local hash table and then merged with the global results
// this will cause much less contention on the global table, but still avoids a sequential
// update
Hashtable<String, Integer> local_results =
new Hashtable<String, Integer>(WordCountJ.HASH_SIZE, WordCountJ.LF);
// grab a file to work on
String cf;
while ((cf = files.poll()) != null) {
try {
BufferedReader input = new BufferedReader(new FileReader(cf));
String text;
// well go line-by-line... maybe this is not the fastest
while ((text = input.readLine()) != null) {
// parse words
Matcher matcher = pattern.matcher(text);
while (matcher.find()) {
String word = matcher.group(1);
if (local_results.containsKey(word)) {
local_results.put(word, 1 + local_results.get(word));
} else {
local_results.put(word, 1);
}
}
}
input.close();
} catch (Exception e) {
System.out.println(" caught a " + e.getClass() + "\n with message: " + e.getMessage());
return;
}
// merge local hashmap with shared one,could have a
// seperate thread do this but that might be cheating
Iterator<Map.Entry<String, Integer>> updates = local_results.entrySet().iterator();
while (updates.hasNext()) {
Map.Entry<String, Integer> kv = updates.next();
String k = kv.getKey();
Integer v = kv.getValue();
synchronized (results) {
if (results.containsKey(k)) {
results.put(k, v + results.get(k));
} else {
results.put(k, v);
}
}
}
local_results.clear();
}
}
public String getLegend(String[] cityMap, int[] POIs) {
char[] ans = new char[POIs.length];
Hashtable hash = new Hashtable();
for (int i = 0; i < cityMap.length; i++) {
for (int j = 0; j < cityMap[i].length(); j++) {
char cur = cityMap[i].charAt(j);
int k = 1;
if (!hash.containsKey(cur)) {
hash.put(cur, k);
} else {
int prev = (int) hash.get(cur);
hash.remove(cur);
hash.put(cur, prev + 1);
}
}
}
Enumeration vals = hash.keys();
while (vals.hasMoreElements()) {
char c = (char) vals.nextElement();
for (int i = 0; i < POIs.length; i++) {
if (hash.get(c) == POIs[i]) {
ans[i] = c;
}
}
}
String str = new String(ans);
return str;
}