Spring入门指南“使用REST访问JPA数据”不起作用

I'm learning Spring using the Getting Started Guides. Right now I'm trying to complete "Accessing JPA Data with REST" guide but my code didn't work, so I tried the "complete" version, and it doesn't work too. So far everytime I import content using Spring Tool Suite (STS), the "complete" version executes as expected, according to the description in the guides, but it's not happening right now.I'm learning Spring using the Getting Started G