为什么用命令行？因为google站点国内很难访问，用Android SDK Manager下载很麻烦。但是我有美国的服务器，用命令行可以升级SDK，然后复制下来。
1. 安装java
2. 下载Android SDK
wget http://dl.google.com/android/android-sdk_r23.0.2-linux.tgz 解压后，进入目录的tools目录，执行：
root@localhost:/opt/android-sdk-linux/tools# ./android list sdk
Refresh Sources:
Fetching https://dl-ssl.google.com/android/repository/addons_list-2.xml
Validate XML
Parse XML
Fetched Add-ons List successfully
Refresh Sources
Fetching URL: https://dl-ssl.google.com/android/repository/repository-10.xml
Validate XML: https://dl-ssl.google.com/android/repository/repository-10.xml
Parse XML: https://dl-ssl.google.com/android/repository/repository-10.xml
Fetching URL: https://dl-ssl.google.com/android/repository/addon.xml
Validate XML: https://dl-ssl.google.com/android/repository/addon.xml
Parse XML: https://dl-ssl.google.com/android/repository/addon.xml
Fetching URL: https://dl-ssl.google.com/android/repository/addon-6.xml
Validate XML: https://dl-ssl.google.com/android/repository/addon-6.xml
Parse XML: https://dl-ssl.google.com/android/repository/addon-6.xml
Fetching URL: https://dl-ssl.google.com/glass/gdk/addon.xml
Validate XML: https://dl-ssl.google.com/glass/gdk/addon.xml
Parse XML: https://dl-ssl.google.com/glass/gdk/addon.xml
Fetching URL: https://dl-ssl.google.com/android/repository/extras/intel/addon.xml
Validate XML: https://dl-ssl.google.com/android/repository/extras/intel/addon.xml
Parse XML: https://dl-ssl.google.com/android/repository/extras/intel/addon.xml
Fetching URL: https://dl-ssl.google.com/android/repository/sys-img/android/sys-img.xml
Validate XML: https://dl-ssl.google.com/android/repository/sys-img/android/sys-img.xml
Parse XML: https://dl-ssl.google.com/android/repository/sys-img/android/sys-img.xml
Fetching URL: https://dl-ssl.google.com/android/repository/sys-img/android-wear/sys-img.xml
Validate XML: https://dl-ssl.google.com/android/repository/sys-img/android-wear/sys-img.xml
Parse XML: https://dl-ssl.google.com/android/repository/sys-img/android-wear/sys-img.xml
Fetching URL: https://dl-ssl.google.com/android/repository/sys-img/android-tv/sys-img.xml
Validate XML: https://dl-ssl.google.com/android/repository/sys-img/android-tv/sys-img.xml
Parse XML: https://dl-ssl.google.com/android/repository/sys-img/android-tv/sys-img.xml
Fetching URL: https://dl-ssl.google.com/android/repository/sys-img/google_apis/sys-img.xml
Validate XML: https://dl-ssl.google.com/android/repository/sys-img/google_apis/sys-img.xml
Parse XML: https://dl-ssl.google.com/android/repository/sys-img/google_apis/sys-img.xml
Fetching URL: https://dl-ssl.google.com/android/repository/sys-img/x86/addon-x86.xml
Validate XML: https://dl-ssl.google.com/android/repository/sys-img/x86/addon-x86.xml
Parse XML: https://dl-ssl.google.com/android/repository/sys-img/x86/addon-x86.xml
Packages available for installation or update: 66
1- Android SDK Tools, revision 23.0.5
2- Android SDK Platform-tools, revision 21
3- Android SDK Build-tools, revision 21.1.1
4- Documentation for Android SDK, API 21, revision 1
5- SDK Platform Android 5.0, API 21, revision 1
6- SDK Platform Android 4.4W.2, API 20, revision 2
7- SDK Platform Android 4.4.2, API 19, revision 4
8- SDK Platform Android 4.3.1, API 18, revision 3
9- SDK Platform Android 4.2.2, API 17, revision 3
10- SDK Platform Android 4.1.2, API 16, revision 5
11- SDK Platform Android 4.0.3, API 15, revision 5
12- SDK Platform Android 4.0, API 14, revision 4
13- SDK Platform Android 3.2, API 13, revision 1
14- SDK Platform Android 3.1, API 12, revision 3
15- SDK Platform Android 3.0, API 11, revision 2
16- SDK Platform Android 2.3.3, API 10, revision 2
17- SDK Platform Android 2.2, API 8, revision 3
18- SDK Platform Android 2.1, API 7, revision 3
19- SDK Platform Android 1.6, API 4, revision 3
20- SDK Platform Android 1.5, API 3, revision 4
21- Samples for SDK API 21, revision 3
22- Samples for SDK API 20, revision 3
23- Samples for SDK API 19, revision 6
24- Samples for SDK API 18, revision 1
25- Samples for SDK API 17, revision 1
26- Samples for SDK API 16, revision 1
27- Samples for SDK API 15, revision 2
28- Samples for SDK API 14, revision 2
29- Samples for SDK API 13, revision 1
30- Samples for SDK API 12, revision 1
31- Samples for SDK API 11, revision 1
32- Samples for SDK API 10, revision 1
33- Samples for SDK API 8, revision 1
34- Samples for SDK API 7, revision 1
35- Google APIs ARM EABI v7a System Image, Google Inc. API 21, revision 2
36- Google APIs Intel x86 Atom_64 System Image, Google Inc. API 21, revision 2
37- Google APIs Intel x86 Atom System Image, Google Inc. API 21, revision 2
38- Google APIs, Android API 21, revision 1
39- Google APIs (x86 System Image), Android API 19, revision 9
40- Google APIs (ARM System Image), Android API 19, revision 9
41- Glass Development Kit Preview, Android API 19, revision 11
42- Google APIs, Android API 18, revision 3
43- Google APIs, Android API 17, revision 3
44- Google APIs, Android API 16, revision 3
45- Google APIs, Android API 15, revision 2
46- Google APIs, Android API 14, revision 2
47- Google APIs, Android API 13, revision 1
48- Google TV Addon, Android API 13, revision 1
49- Google APIs, Android API 12, revision 1
50- Google TV Addon, Android API 12, revision 2
51- Google APIs, Android API 11, revision 1
52- Google APIs, Android API 10, revision 2
53- Google APIs, Android API 8, revision 2
54- Google APIs, Android API 7, revision 1
55- Google APIs, Android API 4, revision 2
56- Google APIs, Android API 3, revision 3
57- Android Support Repository, revision 9
58- Android Support Library, revision 21.0.2
59- Google Play services for Froyo, revision 12
60- Google Play services, revision 21
61- Google Repository, revision 13
62- Google Play APK Expansion Library, revision 3
63- Google Play Billing Library, revision 5
64- Google Play Licensing Library, revision 2
65- Android Auto API Simulators, revision 1
66- Google Web Driver, revision 2这时候可能会遇到adb找不到文件的错误，安装下面两个包：
apt-get install lib32stdc++6
apt-get install lib32z1可以安装了，用下面的命令：
./android update sdk --no-ui --filter 2也可以不加--filter参数，全部下载
android update sdk --no-ui --all --force然后复制到自己的电脑上吧。
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