1. package com.ghb.crp.file;
2.
3. import java.io.BufferedInputStream;
4. import java.io.BufferedOutputStream;
5. import java.io.File;
6. import java.io.FileInputStream;
7. import java.io.FileOutputStream;
8. import java.nio.ByteBuffer;
9. import java.nio.channels.FileChannel;
10.
11. public class FileCopy {
12. public static String src = "f://ss.rmvb";
13. public static String dist = "f://ss2.rmvb";
14.
15. /**
16. * @param args
17. */
18. public static void main(String[] args) {
19. long start = System.currentTimeMillis();
20. copyNew();
21. long end = System.currentTimeMillis();
22. System.out.println("nio 用時： " + (end - start));
23.
24. long start2 = System.currentTimeMillis();
25. copyOld();
26. end = System.currentTimeMillis();
27. System.out.println("io 用時： " + (end - start2));
28. }
29.
30. public static void copyOld() {
31. File srcFile = new File(src);
32. File distFile = new File(dist);
33. if (distFile.exists()) {
34. distFile.delete();
35. }
36. try {
37. FileInputStream fin = new FileInputStream(srcFile);
38. BufferedInputStream buffIn = new BufferedInputStream(fin);
39.
40. FileOutputStream fout = new FileOutputStream(distFile);
41. BufferedOutputStream buffout = new BufferedOutputStream(fout);
42. byte[] bytes = new byte[1024];
43. while (buffIn.read(bytes) > 0) {
44. buffout.write(bytes);
45. }
46. fin.close();
47. buffIn.close();
48. fout.close();
49. buffout.close();
50. } catch (Exception e) {
51. e.printStackTrace();
52. }
53.
54. }
55.
56. public static void copyNew() {
57. try {
58. File srcFile = new File(src);
59. File distFile = new File(dist);
60. if (distFile.exists()) {
61. distFile.delete();
62. }
63.
64. FileInputStream fin = new FileInputStream(srcFile);
65. FileOutputStream fout = new FileOutputStream(distFile);
66. FileChannel inChannel = fin.getChannel();
67. FileChannel outChannel = fout.getChannel();
68. int ByteBufferSize = 1024 * 100;
69. ByteBuffer buff = ByteBuffer.allocate(ByteBufferSize);
70.
71. while (inChannel.read(buff) > 0) {
72. buff.flip();
73. if (inChannel.position() == inChannel.size()) {// 判斷是不是最後一段資料
74. int lastRead = (int) (inChannel.size() % ByteBufferSize);
75. byte[] bytes = new byte[lastRead];
76. buff.get(bytes, 0, lastRead);
77. outChannel.write(ByteBuffer.wrap(bytes));
78. buff.clear();
79. } else {
80. outChannel.write(buff);
81. buff.clear();
82. }
83. }// 這個使用FileChannel 自帶的複製
84. // outChannel.transferFrom(inChannel, 0, inChannel.size());
85. outChannel.close();
86. inChannel.close();
87. fin.close();
88. fout.close();
89. } catch (Exception e) {
90. e.printStackTrace();
91. }
92. }
93. }