报错：Multiple annotations found at this line:

Multiple annotations found at this line:
- String cannot be resolved to a type
- The method getContextPath() from the type HttpServletRequest refers to the missing type String

解决办法:

首先 右击该项目 - Build Path - Configure Build Path ， 在 Libraries 选项下，会发现有个出错的jre Libraries，将其Remove掉。

然后 右击该项目 - Build Path - Add Library， 选择JRE System Library，选择Workspace default JRE(此前JDK已成功安装并配置好)， 然后 Finish 。