Java implementation method of obtaining project file path

this.getClass().getResource("/").getPath().substring(1) The path obtained is E:/myeclipse/test/WebRoot/WEB-INF/classes/, which is the home directory.

this.getClass().getResource("").getPath().substring(1) The path obtained is E:/myeclipse/test/WebRoot/WEB-INF/classes/net/hncu/db/, which is the relative path of this file path.

this.getClass().getResource(".").getPath().substring(1) has the same effect as this.getClass().getResource("").getPath().substring(1)