Java字符统计并排序

Java字符统计

package test;
import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Hashtable;
import java.util.List;
/**
* 对一个保存英文文章的文本文档进行统计，最后给出每个英文字符的出现次数，按降幂排列
*/
public class SortedCharactersCounter {
static final Hashtable<String, Integer> h = new Hashtable<String, Integer>();
public static void main(String args[]) {
try {
FileInputStream fis = new FileInputStream("str.txt");
InputStreamReader dis = new InputStreamReader(fis);
BufferedReader reader = new BufferedReader(dis);
String s = null;
//统计字母
while ((s = reader.readLine()) != null) {
for (int i = 0; i < s.length(); i++) {
int temp = 0;
if (h.containsKey(String.valueOf(s.charAt(i))))
temp = h.get(String.valueOf(s.charAt(i))) + 1;
else
temp = 1;
h.remove(String.valueOf(s.charAt(i)));
h.put(String.valueOf(s.charAt(i)), temp);
}
}
dis.close();
//排序
List<String> sortedKeys = new ArrayList<String>(h.keySet());
Collections.sort(sortedKeys, new Comparator<Object>() {
public int compare(Object arg0, Object arg1) {
return h.get(arg1) - (h.get(arg0));
}
});

// 输出
for (String str : sortedKeys)
System.out.println("'" + str + "':" + h.get(str));
} catch (IOException e) {
}
}
}