JDK6.0学习笔记（六）复制文件

 

1. /**
2.  * 复制文件
3.  * 运行命令行 java CopyFile C:\1.txt D:1.txt
4.  * */
6. import java.io.*;
7. import java.text.*;
8. import java.util.*;
10. public class CopyFile {
11.     public static void main(String[] args) throws IOException {
12.         new CopyFile().copy(args[0], args[1], Integer.parseInt(args[2]));
13.     }
15.     public int copy(String source_name, String dest_name, int type)
16.             throws IOException {
17.         File source_file = new File(source_name);
18.         File dest_file = new File(dest_name);
20.         FileInputStream source = null;
21.         FileOutputStream destination = null;
22.         byte[] buffer;
23.         int bytes_read;
24.         int result = 0;
26.         try {
27.             if (!source_file.exists() || !source_file.isFile())
28.                 throw new RuntimeException("FileCopy: no such source file: "
29.                         + source_name);// 源文件不存在
30.             if (!source_file.canRead())
31.                 throw new RuntimeException("FileCopy: source file "
32.                         + "is unreadable: " + source_name);// 源文件不可读
34.             if (dest_file.exists()) {
35.                 if (dest_file.isFile()) {
36.                     if (type == 1) // 覆盖
37.                     {
38.                         dest_file.delete();
39.                         result = 1;
40.                     } else // 不覆盖
41.                     {
42.                         result = 2;
43.                         return result;
44.                     }
45.                 } else
46.                     throw new RuntimeException("FileCopy: destination "
47.                             + "is not a file: " + dest_name);// 目标是目录而不是文件
48.             } else {
49.                 File parentdir = new File(dest_file.getParent());
50.                 if (!parentdir.exists())
51.                     throw new RuntimeException("FileCopy: destination "
52.                             + "directory doesn't exist: " + dest_name);// 目标路径不存在
53.                 if (!parentdir.canWrite())
54.                     throw new RuntimeException("FileCopy: destination "
55.                             + "directory is unwriteable: " + dest_name);// 目标路径不可写
56.             }
58.             // 复制文件
59.             source = new FileInputStream(source_file);
60.             destination = new FileOutputStream(dest_file);
61.             buffer = new byte[1024];
62.             while (true) {
63.                 bytes_read = source.read(buffer);
64.                 if (bytes_read == -1) {
65.                     break;
66.                 }
67.                 destination.write(buffer, 0, bytes_read);
68.             }
69.         } finally {
70.             if (source != null) {
71.                 try {
72.                     source.close();
73.                 } catch (IOException e) {
74.                 }
75.             }
76.             if (destination != null) {
77.                 try {
78.                     destination.close();
79.                 } catch (IOException e) {
80.                 }
81.             }
83.             return result;
84.         }
85.     }