Eclipse无法识别导入的json.jar文件

so I'm making a web project for school and I had to use some JSON. I wanted to parse a JSON string to a JSONObject using org.json.simple.parser.JSONParser. I included json-simple-1.1.1.jar into my project build path. However, I'm getting an error whenever I try to run my project on my tomcat server v8.0.so I'm making a web project for school and I ha