[JAVA] [Spring MVC] How to pass path variables

How to receive path variables in Spring, how to pass to redirect destination Memo

How to receive a path variable

// (1)
@GetMapping("{name}")
public String detail(@PathVariable String name) {
    return "detail";
}

// (2)
@GetMapping("idol/{name}")
public String idolDetail(@PathVariable("name") String idolName) {
    return "idol/detail";
}

// (3)
@GetMapping("unit/{unitId}/idol/{idolId}")
public String idolDetail(@PathVariable("unitId") Integer unitId, @PathVariable("idolId") Integer idolId) {
    return "idol/detail";
}

If you want to use the value contained in the path in the process of the method, use the path variable ({variable name}) format in the part where the value you want to receive is entered in the Mapping annotation, and set the corresponding argument to @PathVariable. Specify .

(1) If the path variable name and the variable name actually used are the same, the value attribute of @PathVariable can be omitted. (2) If the variable name is different, specify the path variable name in the value attribute of @PathVariable. (3) Multiple is possible.

How to pass a path variable to the redirect destination

// (1)
@PostMapping("idol/{name}/update")
public String update(@PathVariable String name) {
    return "redirect:/idol/{name}";
}

// (2)
@PostMapping("redirect")
public String redirect(RedirectAttributes redirectAttributes) {
    redirectAttributes.addAttribute("name", "Jinka Osaki");
    return "redirect:/idol/{name}";
}

(1) A variable once received as a path variable can be passed to the redirect destination as it is. In the case of the above code, if you send a POST request to / idol / Kiriko Yuya / update, the URL of the redirect destination will be / idol / Kiriko Yuya. (2) If the variable added by using the ʻaddAttributemethod of RedirectAttributes is included in the redirect destination path variable, it is expanded as it is as a path variable. In the above case, the redirect destination URL will be/ idol / Osaki Jinka`.

(2) may be a simple string concatenation if it is not necessary to enter a value separately.

reference

Official Reference Spring MVC controller arguments Thorough introduction to Spring Java application development with Spring Framework