最近在线升级一直卡在最后，突发奇想摸索出了离线升级办法。
先下载IDEA更新文件
https://download.jetbrains.com/idea/IU-193.7288.26-201.8743.12-patch-jbr11-win.jar
执行
java -jar IU-193.7288.26-201.8743.12-patch-jbr11-win.jar "C:\Program FilesJetBrains\IntelliJ IDEA 2019.3.4"
Microsoft Windows [版本 6.1.7601]
版权所有 (c) 2009 Microsoft Corporation。保留所有权利。
C:Windowssystem32>cd C:UsersAdministratorDownloads
C:UsersAdministratorDownloads>java -jar IU-193.7288.26-201.8743.12-patch-jbr1
1-win.jar "C:\Program FilesJetBrains\IntelliJ IDEA 2019.3.4"
Extracting patch file...
From IntelliJ IDEA (build 193.7288.26) to IntelliJ IDEA (build 201.8743.12)
Validating installation...
Validation info:
ERROR bin/idea.exe: Modified
Selected REPLACE for bin/idea.exe
Backing up files...
Applying patch...
Cleaning up...
C:UsersAdministratorDownloads>
更新完成。