Java查找指定文件中指定字符的个数

 1 package lwl.youweb2.test;
 2 
 3 import java.io.BufferedReader;
 4 import java.io.FileReader;
 5 import java.io.IOException;
 6 import java.util.regex.Matcher;
 7 import java.util.regex.Pattern;
 8 
 9 /**
10  * 查找指定文件中指定字符的个数
11  *
12  * @author liuwenlong
13  * @create 2020-08-20 10:48:27
14  */
15 @SuppressWarnings("all")
16 public class test01 {
17     static {
18         String args[] = {"d:\\123.txt", "张三"};
19         main(args);
20     }
21 
22     public static void main(String[] args) {
23         if (args.length != 2) {
24             return;
25         }
26         BufferedReader br = null;
27         FileReader fr = null;
28         try {
29             fr = new FileReader(args[0]);
30             br = new BufferedReader(fr);
31             int cnt = 0;
32             String str = null;
33             while ((str = br.readLine()) != null) {
34                 Pattern a = Pattern.compile(args[1]);
35                 Matcher m = a.matcher(str);
36                 while (m.find()) {
37                     cnt++;
38                 }
39             }
40             System.out.println("[" + args[1] + "]的数量：" + cnt);
41         } catch (Exception e) {
42             System.err.println(e.getMessage());
43         } finally {
44             try {
45                 fr.close();
46             } catch (IOException e) {
47                 e.printStackTrace();
48             }
49         }
50     }
51 
52 }