2
3import java.io.File;
4import java.io.IOException;
5import java.io.InputStream;
6import java.io.RandomAccessFile;
7import java.net.HttpURLConnection;
8import java.net.MalformedURLException;
9import java.net.URL;
10
11//斷點續傳
12public class DownLoad {
13
14 public static void down(String URL, long nPos, String savePathAndFile) {
15 try {
16 URL url = new URL(URL);
17 HttpURLConnection /media/0/16/8678/8678.flv";
58 String savePath = "F:\\";
59 String fileName = url.substring(url.lastIndexOf("/"));
60 String fileNam=fileName;
61 HttpURLConnection conn = null;
62 try {
63 conn = (HttpURLConnection) (new URL(url)).openConnection();
64 } catch (Exception e) {
65 e.printStackTrace();
66 }
67 File file = new File(savePath + fileName);
68 // 獲得遠程文件大小
69 long remoteFileSize = getRemoteFileSize(url);
70 System.out.println("遠程文件大小="+remoteFileSize);
71 int i = 0;
72 if (file.exists()) {
73 // 先看看是否是完整的，完整，換名字，跳出循環，不完整，繼續下載
74 long localFileSize = file.length();
75 System.out.println("已有文件大小為:"+localFileSize);
76
77 if (localFileSize < remoteFileSize) {
78 System.out.println("文件續傳");
79 down(url, localFileSize, savePath + fileName);
80 }else{
81 System.out.println("文件存在，重新下載");
82 do{
83 i++;
84 fileName = fileNam.substring(0, fileNam.indexOf(".")) + "(" + i
85 + ")" + fileNam.substring(fileNam.indexOf("."));
86
87 file = new File(savePath + fileName);
88 }while(file.exists());
89 try {
90 file.createNewFile();
91 } catch (IOException e) {
92 e.printStackTrace();
93 }
94 down(url, 0, savePath + fileName);
95 }
96 // 下面表示文件存在，改名字
97
98 } else {
99 try {
100 file.createNewFile();
101 System.out.println("下載中");
102 down(url, 0, savePath + fileName);
103 } catch (IOException e) {
104 e.printStackTrace();
105 }
106 }
107 }}
108