在安装完IntelliJ IDEA之后，默认会在windows的系统盘用户文件夹中创建配置等文件。在我只有32G的SSD盘中，怎么能让它如此，不爽呀。。占用到现在都快1G了。好吧。今天把她解决了。
找到安装路径下有个属性文件idea.properties（比如：D:IntelliJ IDEAin），打开此文件，前面三行就说了：
# Use ${idea.home} macro to specify location relative to IDE installation home # Also use ${xxx} where xxx is any java property (including defined in previous lines of this file) to refer to its value # Note for Windows users: please make sure you're using forward slashes. I.e. c:/idea/system
接下来四行中看看应该就知道什么意思了，比如：idea.config.path=${user.home}/.IntelliJIdea12/config
修改成你要设置的路径就好了，修改后最终这几行如下：
#---------------------------------------------------------------------
# Uncomment this option if you want to customize path to IDE config folder. Make sure you're using forward slashes
#---------------------------------------------------------------------
idea.config.path=D:/IntelliJ IDEA/.IntelliJIdea12/config
#---------------------------------------------------------------------
# Uncomment this option if you want to customize path to IDE system folder. Make sure you're using forward slashes
#---------------------------------------------------------------------
idea.system.path=D:/IntelliJ IDEA/.IntelliJIdea12/system
#---------------------------------------------------------------------
# Uncomment this option if you want to customize path to user installed plugins folder. Make sure you're using forward slashes
#---------------------------------------------------------------------
idea.plugins.path=D:/IntelliJ IDEA/.IntelliJIdea12/config/plugins
#---------------------------------------------------------------------
# Uncomment this option if you want to customize path to IDE logs folder. Make sure you're using forward slashes.
#---------------------------------------------------------------------
idea.log.path=D:/IntelliJ IDEA/.IntelliJIdea12/system/log注意呀：纠结了好好久，怎么改了没效果，后面发现
#idea.config.path=D:/IntelliJ IDEA/.IntelliJIdea12/config这多了个#号啊。要把这个#号去掉打开这行配置才行
这下子可以把C盘占用的删除了！！！不过注意把以前配置好的转移备份