1 package cn.temptation;
  2 
  3 import java.io.BufferedInputStream;
  4 import java.io.BufferedOutputStream;
  5 import java.io.FileInputStream;
  6 import java.io.FileOutputStream;
  7 import java.io.IOException;
  8 
  9 public class Sample27 {
 10     public static void main(String[] args) throws
 
 IOException {
 11         // 比較IO操作的耗時
 12         long startTime = System.currentTimeMillis();
 13         
 14 //        method1("D:\\KuGou\\田馥甄 - 傻子.mp3", "D:\\田馥甄 - 傻子.mp3");
 15 //        method2("D:\\KuGou\\田馥甄 - 傻子.mp3", "D:\\田馥甄 - 傻子.mp3");
 16 //        method3("D:\\KuGou\\田馥甄 - 傻子.mp3", "D:\\田馥甄 - 傻子.mp3");
 

 17         method4("D:\\KuGou\\田馥甄 - 傻子.mp3", "D:\\田馥甄 - 傻子.mp3");
 18         
 19         long endTime = System.currentTimeMillis();
 20         
 21         System.out.println("耗時：" + (endTime - startTime));
 22         
 23         // 顯然，使用緩衝區比不使用緩衝區耗時少了很多
 24         // 類比理解：古代歐洲人寫字，拿著棍子一次蘸一滴墨；古代中國人寫字，拿著毛筆一次蘸一管墨（容器思想）
 

 25     }
 26     
 27     /**
 28      * 位元組流一次讀寫一個位元組（耗時：38080）
 29      * @param src
 30      * @param target
 31      * @throws IOException 
 32      */
 33     public static void method1(String src, String target) throws IOException {
 34         FileInputStream fis = new FileInputStream(src);
 35         FileOutputStream fos = new FileOutputStream(target);
 36         
 37         int ch = 0;
 38         
 39         while ((ch = fis.read()) != -1) {
 40             fos.write(ch);
 41             fos.flush();
 42         }
 43         
 44         fos.close();
 45         fis.close();
 46     }
 47     
 48     /**
 49      * 位元組流一次讀寫一個位元組陣列（位元組陣列作為緩衝區）（耗時：78）
 50      * @param src
 51      * @param target
 52      * @throws IOException 
 53      */
 54     public static void method2(String src, String target) throws IOException {
 55         FileInputStream fis = new FileInputStream(src);
 56         FileOutputStream fos = new FileOutputStream(target);
 57         
 58         byte[] arr = new byte[1024];
 59         int length = 0;
 60         
 61         while ((length = fis.read(arr)) != -1) {
 62             fos.write(arr, 0, length);
 63             fos.flush();
 64         }
 65         
 66         fos.close();
 67         fis.close();
 68     }
 69     
 70     /**
 71      * 緩衝位元組流一次讀寫一個位元組（耗時：23922）
 72      * @param src
 73      * @param target
 74      * @throws IOException 
 75      */
 76     public static void method3(String src, String target) throws IOException {
 77         BufferedInputStream bis = new BufferedInputStream(new FileInputStream(src));
 78         BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(target));
 79         
 80         int ch = 0;
 81         
 82         while ((ch = bis.read()) != -1) {
 83             bos.write(ch);
 84             bos.flush();
 85         }
 86         
 87         bos.close();
 88         bis.close();
 89     }
 90     
 91     /**
 92      * 緩衝位元組流一次讀寫一個位元組陣列（位元組陣列作為緩衝區）（耗時：78）
 93      * @param src
 94      * @param target
 95      * @throws IOException 
 96      */
 97     public static void method4(String src, String target) throws IOException {
 98         BufferedInputStream bis = new BufferedInputStream(new FileInputStream(src));
 99         BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(target));
100         
101         byte[] arr = new byte[1024];
102         int length = 0;
103         
104         while ((length = bis.read(arr)) != -1) {
105             bos.write(arr, 0, length);
106             bos.flush();
107         }
108         
109         bos.close();
110         bis.close();
111     }
112 }