[FIXED] Spring boot using pathvariable to get hold of an id from url

Issue

I'm struggling with attaining an id from the url to use as a parameter in my read() method. I read and have seen dusin of examples of using @PathVariable and I can't see why this should not work.

This is my controller class.

@GetMapping("details/{id}")
    public String read(@PathVariable int employeeId, Model model)
    {

        model.addAttribute("students_data", studentsRepo.read(employeeId));

        //the line underneath will work using as an example the int 2 in the parameter. But I want the int coming from the url.
        //model.addAttribute("students_data", studentsRepo.read(2));

        return "details";
    }

I get the error on the details page:

Fri Jan 03 12:13:44 CET 2020
There was an unexpected error (type=Not Found, status=404).
No message available

Example of how the url could look is:

http://localhost:8080/details?id=2

Solution

The URL http://localhost:8080/details?id=2 that you have shared contain @RequestParam and not @PathVariable

If you want to use @RequestParam then your API signature should be

    @GetMapping("details/")
    public String read(@RequestParam("id") int employeeId, Model model)
    {
       "details";
    }

If you want to use @PathVariable then your API should be

    @GetMapping("details/{id}")
    public String read(@PathVariable("id") int employeeId, Model model)
    {
       "details";
    }

Please check the difference between the two https://javarevisited.blogspot.com/2017/10/differences-between-requestparam-and-pathvariable-annotations-spring-mvc.html

Answered By - dassum