yarn使用時候報錯資訊：

Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

1. 檢測yarn版本 yarn version （成功）

D:\me\angular\ng-app>yarn version
Hadoop 2.8.3
Subversion https://git-wip-us.apache.org/repos/asf/hadoop.git -r b3fe56402d908019d99af1f1f4fc65cb1d1436a2
Compiled by jdu on 2017-12-05T03:43Z
Compiled with protoc 2.5.0
From source with checksum 9ff4856d824e983fa510d3f843e3f19d
This command was run using /D:/dev/hadoop-2.8.3/share/hadoop/common/hadoop-common-2.8.3.jar
 

2. 檢測yarn版本 yarn --version  (報錯)

C:\Users\92809>yarn --version
Unrecognized option: --version
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

3. 安裝依賴包 （報錯）

D:\me\angular\ng-app>yarn install
錯誤: 找不到或無法載入主類 install

4. 最後沒辦法重新下載windows安裝包（ 

   安裝 -> 測試 -> 報錯 -> 檢測原因 -> 沒有配置環境變數 -> 繼續報錯,檢測原因 -> java安裝環境中有預設的yarn -> 環境變數配置在它前面

5. 測試 （成功）

C:\Users\92809>yarn --version
1.10.1

6. 連線淘寶映象

（1）檢視原本的registry

   D:\me\angular\ng-app>yarn config get registry
   https://registry.yarnpkg.com
 

（2）更新為淘寶映象

  D:\me\angular\ng-app>yarn config set registry http://registry.npm.taobao.org/
  yarn config v1.10.1
  success Set "registry" to "http://registry.npm.taobao.org/".
  Done in 0.04s.

7. 重新安裝依賴包 （成功）

D:\me\angular\ng-app>yarn install
yarn install v1.10.1
info No lockfile found.
[1/4] Resolving packages...
⠠ [email protected]^1.1.7

8. 大功告成，搞了一天多，終於解決了，給自己鼓個掌 ~~