java IO流 ---文件的读写操作

Posted 2020-08-22

 

 1 package com.io;
 2 import java.io.File;
 3 import java.io.FileInputStream;
 4 import java.io.FileOutputStream;
 5 import java.io.FileNotFoundException;
 6 import java.io.IOException;
 7 public class Test2 {
 8 
 9     /**
10      * @param args
11      * @throws IOException 
12      */
13     public static void main(String[] args)  {
14        
15         File file1 = new File("C:\\Users\\Coda\\Desktop\\google1.jpg");
16         File file2 = new File("C:\\Users\\Coda\\Desktop\\图片储存\\dd.jpg");
17         
18             CopyIt(file1,file2);
19         
20     }
21     
22     public static void CopyIt( File file1, File file2) {
23 
24         FileInputStream fileInputStream;
25         try {
26             fileInputStream = new FileInputStream(file1);
27         } catch (FileNotFoundException e) {
28             System.out.println("文件路径错误");
29              throw new RuntimeException(e);
30         }
31         FileOutputStream fileOutputStream = null;
32         try {
33             fileOutputStream = new FileOutputStream(file2,true);
34         } catch (FileNotFoundException e) {
35             // TODO Auto-generated catch block
36             e.printStackTrace();
37         }
38         
39         byte[]b = new byte[2];
40         int count = 0;
41         try {
42             while((count = fileInputStream.read(b))!=-1){
43   
44                 fileOutputStream.write(b);
45       
46             }
47         } catch (IOException e) {
48               System.out.println("写入文件失败");
49             throw new RuntimeException(e);
50             
51         } finally{
52               try {
53                 fileOutputStream.close();
54             } catch (IOException e) {
55                 System.out.println("文件正在运行，无法关闭");
56                 throw new RuntimeException(e);
57             }
58                try {
59                 fileInputStream.close();
60             } catch (IOException e) {
61                 System.out.println("文件正在运行，无法关闭");
62                 throw new RuntimeException(e);
63             }  
64             System.out.println("文件复制成功");
65         }
66             
67   }
68 
69 }