Sean

为什么转换为json的时候 ，会失败。但是把声明外健的字段给屏蔽掉。就可以成功

1

@RequestMapping(value = "/admin/users", method = RequestMethod.GET) public String getUsers(ModelMap modelMap) throws JsonProcessingException { List userList = userRepository.findAll(); ObjectMapper mapper = new ObjectMapper(); System.out.println(mapper.writeValueAsString(userList)); ／／这里会失败 ``` modelMap.addAttribute("userList", userList); return "admin/users"; }...

不知道怎么搞的，只能添加一篇文章，添加第二篇文章就报错。

1

报这样的错 HTTP Status 500 - Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException: could not execute statement; SQL [n/a]; constraint [PRIMARY]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement 这是什么原因

fatal error: 'sys/types.h' file not found

4

mac:kctcontract kcmac$ go get -u github.com/beego/bee # github.com/beego/bee/vendor/github.com/derekparker/delve/proc In file included from ../../Documents/GO/src/github.com/beego/bee/vendor/github.com/derekparker/delve/proc/proc_darwin.go:3: ./proc_darwin.h:1:10: fatal error: 'sys/types.h' file not found #include ^~~~~~~~~~~~~ 1 error generated. Why