用java實現從kernel.ubuntu.com下載核心的小工具

現在的最新的LTS版本是4.19，目前已經更新到4.19.13了。

Kernel的更新通知裡，經常有下面的陳述：

作為一個聽勸的人，沒事就刷一刷https://www.kernel.org/，看看有沒有更新。

有更新之後，再刷一刷kernel.ubuntu.com看看Ubuntu有沒有更新核心。

下載deb包，執行下面安裝核心之後在重啟。

sudo dpkg -i *.deb

思路

希望通過下面命令列，可以從kernel.ubuntu.com下載核心的deb檔案。

java -jar getKernel.jar v4.19.13
 

java程式getkernel.jar先通過命令列引數獲得版本。

將版本拼接成網址https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19.13/

從網址讀取網頁，HttpURLConnection

並從中解析deb的超連結，java.util.regex.Pattern、Matcher

在把amd64的所有包都儲存成檔案。　　

估計用指令碼呼叫wget可能更快。 

貼程式碼

App.java

  1 package getKernel;
  2 
  3 import java.io.BufferedReader;
 
  4 import java.io.FileNotFoundException;
  5 import java.io.FileOutputStream;
  6 import java.io.IOException;
  7 import java.io.InputStream;
  8 import java.io.InputStreamReader;
  9 import java.net.HttpURLConnection;
 10 import java.net.URL;
 11 import java.util.regex.Matcher;
 12 import java.util.regex.Pattern;
 
 13 
 14 public class App {
 15 
 16     public static void main(String[] args) {
 17         String targetIndex = "https://kernel.ubuntu.com/~kernel-ppa/mainline/" + args[0] + "/";
 18 
 19         String strHeaderAll=null;
 20         String strHeaderAmd64=null;
 21         String strImageUnsignedAmd64=null;
 22         String strModulesAmd64=null;
 23 
 24         boolean foundHeaderAll = false;
 25         boolean foundHeaderAmd64 = false;
 26         boolean foundImageAmd64 = false;
 27         boolean foundModulesAmd64 = false;
 28 
 29         // 1 get file
 30         FileOutputStream fs = null;
 31         BufferedReader br = null;
 32         Pattern pattern = null;
 33         Matcher matcher = null;
 34 
 35         try {
 36             URL url = new URL(targetIndex);
 37             HttpURLConnection conn = (HttpURLConnection) url.openConnection();
 38             conn.connect();
 39             if (conn.getResponseCode() == 200) {
 40                 InputStream inStream = conn.getInputStream();
 41                 br = new BufferedReader(new InputStreamReader(inStream));
 42                 String str;
 43                 while ((str = br.readLine()) != null) {
 44 
 45                     if (!foundHeaderAll) {
 46                         pattern = Pattern.compile("href=\"(linux-headers-\\S+all.deb)\"", Pattern.CASE_INSENSITIVE);
 47                         matcher = pattern.matcher(str);
 48                         if (matcher.find()) {
 49                             strHeaderAll = targetIndex + matcher.group(1);
 50                             System.out.println(strHeaderAll);
 51                             foundHeaderAll = true;
 52                         }
 53                     }
 54                     if (!foundHeaderAmd64) {
 55                         pattern = Pattern.compile("href=\"(linux-headers-\\S+amd64.deb)\"", Pattern.CASE_INSENSITIVE);
 56                         matcher = pattern.matcher(str);
 57                         if (matcher.find()) {
 58                             strHeaderAmd64 = targetIndex + matcher.group(1);
 59                             System.out.println(strHeaderAmd64);
 60                             foundHeaderAmd64 = true;
 61                         }
 62                     }
 63                     if (!foundImageAmd64) {
 64                         pattern = Pattern.compile("href=\"(linux-image-unsigned\\S+amd64.deb)\"",
 65                                 Pattern.CASE_INSENSITIVE);
 66                         matcher = pattern.matcher(str);
 67                         if (matcher.find()) {
 68                             strImageUnsignedAmd64 = targetIndex + matcher.group(1);
 69                             System.out.println(strImageUnsignedAmd64);
 70                             foundImageAmd64 = true;
 71                         }
 72 
 73                     }
 74                     if (!foundModulesAmd64) {
 75                         pattern = Pattern.compile("href=\"(linux-modules\\S+amd64.deb)\"", Pattern.CASE_INSENSITIVE);
 76                         matcher = pattern.matcher(str);
 77                         if (matcher.find()) {
 78                             strModulesAmd64 = targetIndex + matcher.group(1);
 79                             System.out.println(strModulesAmd64);
 80                             foundModulesAmd64 = true;
 81                         }
 82                     }
 83                 }
 84 
 85                 SaveFile.saveUrl2file(strHeaderAll);
 86                 SaveFile.saveUrl2file(strHeaderAmd64);
 87                 SaveFile.saveUrl2file(strImageUnsignedAmd64);
 88                 SaveFile.saveUrl2file(strModulesAmd64);
 89 
 90             }
 91 
 92         } catch (FileNotFoundException e) {
 93             e.printStackTrace();
 94         } catch (IOException e) {
 95             e.printStackTrace();
 96         } finally {
 97             if (br != null) {
 98                 try {
 99                     br.close();
100                 } catch (IOException e1) {
101                     e1.printStackTrace();
102                 }
103             }
104             if (fs != null) {
105                 try {
106                     fs.close();
107                 } catch (IOException e) {
108                     e.printStackTrace();
109                 }
110             }
111         }
112     }
113 
114 }

SaveFile.java

 1 package getKernel;
 2 
 3 import java.io.FileNotFoundException;
 4 import java.io.FileOutputStream;
 5 import java.io.IOException;
 6 import java.io.InputStream;
 7 import java.net.HttpURLConnection;
 8 import java.net.URL;
 9 
10 public class SaveFile {
11 
12     public static void saveUrl2file(String strPath) {
13         if (strPath == null)
14             return;
15         FileOutputStream fs = null;
16         try {
17             int bytesum = 0;
18             int byteread = 0;
19 
20             URL url = new URL(strPath);
21             HttpURLConnection conn = (HttpURLConnection) url.openConnection();
22             conn.connect();
23             if (conn.getResponseCode() == 200) {
24                 InputStream inStream = conn.getInputStream();
25                 int size = conn.getContentLength();
26                 String filename = strPath.substring(strPath.lastIndexOf('/')+1, strPath.length());
27                 System.out.println(filename);
28                 fs = new FileOutputStream(filename);
29 
30                 byte[] buffer = new byte[1024*1024];
31                 while ((byteread = inStream.read(buffer)) != -1) {
32                     bytesum += byteread;
33                     fs.write(buffer, 0, byteread);
34                     String strPgs = "Progress:"+bytesum * 100 / size;
35                     System.out.printf(strPgs);
36                     for (int k = 0; k < strPgs.length(); k++)
37                         System.out.print("\b");
38                 }
39             }
40 
41         } catch (FileNotFoundException e) {
42             e.printStackTrace();
43         } catch (IOException e) {
44             e.printStackTrace();
45         } finally {
46 
47             if (fs != null) {
48                 try {
49                     fs.close();
50                 } catch (IOException e) {
51                     e.printStackTrace();
52                 }
53             }
54         }
55     }
56 }