1 package multiplethread;
  2 
  3 import java.io.BufferedReader;
  4 import java.io.File;
  5 import java.io.FileNotFoundException;
  6 import java.io.FileReader;
  7 import java.io.IOException;
  8 
  9 public class searchFileInDirectory {
 10     // 实现Runnable接口方式的多线程
 11     public static void funcThread1(String path) {
 12         File f = new File(path);
 13         if (f.exists()) {
 14             File[] fs = f.listFiles();
 15             for (File x : fs) {
 16                 if (x.isDirectory())
 17                     funcThread1(x.getAbsolutePath());
 18                 if (x.isFile() && x.getName().contains(".java")) {
 19                     new Thread(new searchInFile(x)).start();
 20                 }
 21             }
 22         }
 23     }
 24 
 25     public static void checkFile(File x) {
 26         Thread t = new Thread() {
 27             public void run() {
 28                 try (BufferedReader br = new BufferedReader(new FileReader(x));) {
 29                     while (true) {
 30                         String line = br.readLine();
 31                         if (line == null)
 32                             break;
 33                         if (line.contains("Magic")) {
 34                             System.out.printf("找到目标字符串\"Magic\",在文件%s%n", x.getAbsoluteFile());
 35                         }
 36                     }
 37                 } catch (IOException e) {
 38                     // TODO Auto-generated catch block
 39                     e.printStackTrace();
 40                 }
 41             }
 42 
 43         };
 44         t.start();
 45     }
 46 
 47     // 匿名类的方式的多线程
 48     public static void funcThread2(String path) {
 49         File f = new File(path);
 50         if (f.exists()) {
 51             File[] fs = f.listFiles();
 52             for (int i = 0; i < fs.length; i++) {
 53                 File x = fs[i];
 54                 if (x.isDirectory()) {
 55                     funcThread2(x.getAbsolutePath());
 56                 }
 57                 if (x.isFile() && x.getName().contains(".java")) {
 58                     checkFile(x); // 理论上直接写到这里可以，但是为了美观便于阅读，就单独写到checkFile()中
 59                 }
 60             }
 61 
 62         }
 63     }
 64 
 65     // 单线程
 66     public static void funcNoThread(String path) {
 67         File f = new File(path);
 68         if (f.exists()) {
 69             File[] fs = f.listFiles();
 70             for (File x : fs) {
 71                 if (x.isDirectory())
 72                     funcNoThread(x.getAbsolutePath());
 73                 if (x.isFile() && x.getName().contains(".java")) {
 74                     try (BufferedReader br = new BufferedReader(new FileReader(x));) {
 75                         while (true) {
 76                             String line = br.readLine();
 77                             if (line == null)
 78                                 break;
 79                             if (line.contains("Magic")) {
 80                                 System.out.printf("找到目标字符串\"Magic\",在文件%s%n", x.getAbsoluteFile());
 81                             }
 82                         }
 83                     } catch (IOException e) {
 84                         // TODO Auto-generated catch block
 85                         e.printStackTrace();
 86                     }
 87 
 88                 }
 89             }
 90         }
 91     }
 92 
 93     public static void main(String[] args) {
 94         String path = "F:\\project\\javastudy";
 95         long st1 = System.currentTimeMillis();
 96         funcThread1(path);
 97         long et1 = System.currentTimeMillis();
 98         System.out.printf("多线程Thread1下花费时间：%d ms", et1 - st1);
 99 
100         long st2 = System.currentTimeMillis();
101         funcThread2(path);
102         long et2 = System.currentTimeMillis();
103         System.out.printf("多线程Thread2下花费时间：%d ms", et2 - st2);
104 
105         long st3 = System.currentTimeMillis();
106         funcNoThread(path);
107         long et3 = System.currentTimeMillis();
108         System.out.printf("单线程下花费时间：%d ms", et3 - st3);
109     }
110 }