intellij IDEA在第一次启动时，会在${user.home}目录下建立以.IntelliJIdea开头的文件夹，用来存放IDEA的配置信息、插件和缓存信息。随着工具使用时间越多，这个文件夹会越来越大。如果用户目录和系统盘在一个分区，那系统盘分区可用空间就会变小，系统重装时，这个目录还会被删除。
于是我们需要将此目录修改到其他分区，修改很简单，如下：
在IDEA安装目录的bin文件夹中找到idea.properties文件，我们需要里面的几项内容：
# Use ${idea.home} macro to specify location relative to IDE installation home.
# Use ${xxx} where xxx is any Java property (including defined in previous lines of this file) to refer to its value.
# Note for Windows users: please make sure you're using forward slashes (e.g. c:/idea/system).
#---------------------------------------------------------------------
# Uncomment this option if you want to customize path to IDE config folder. Make sure you're using forward slashes.
#---------------------------------------------------------------------
#打开confi的配置
# idea.config.path=${user.home}/config
#---------------------------------------------------------------------
# Uncomment this option if you want to customize path to IDE system folder. Make sure you're using forward slashes.
#---------------------------------------------------------------------
#打开system的配置
# idea.system.path=${user.home}/system
#---------------------------------------------------------------------
# Uncomment this option if you want to customize path to user installed plugins folder. Make sure you're using forward slashes.
#---------------------------------------------------------------------
#打开plugins的配置
# idea.plugins.path=${idea.config.path}/plugins
#---------------------------------------------------------------------
# Uncomment this option if you want to customize path to IDE logs folder. Make sure you're using forward slashes.
#---------------------------------------------------------------------
#打开log的配置
# idea.log.path=${idea.system.path}/log
将idea.config.path和idea.system.path里面的${user.home}改成将要存放目录的位置，我这里修改为D:/Program/JetBrains，然后重启即可。
