Spring Boot url处理多种情况

@RestController //作用等同于@Controller + @ResponseBody
// 统一加上前缀
    @RequestMapping("/prefix")
public class ParaController {
    @GetMapping({"/firstrequest"})
    public String firstRequest() {
        return "第一个springboot接口";
    }

    // 将参数放到request请求中
    @GetMapping("/requestParam")
    public int requestParam(@RequestParam int num) {
        return num;
    }

    //将参数直接放在URL里
    @GetMapping("/pathParam/{param}")
    public String pathParam(@PathVariable String param) {
        return param;
    }

    //为一个方法，绑定多一个url
    @GetMapping({"/multiurl1", "/multiurl2"})
    public String multiurl(@RequestParam String str) {
        return str;
    }

    //给参数设置默认值
    @GetMapping({"/required"})
    public int required(@RequestParam(required = false, defaultValue = "0") int num) {
        return num;
    }
    //返回json数据
    @GetMapping({"/json"})
    public Map<String, Object> json() {
        Map<String, Object> result = new HashMap<>();
        result.put("code", 0);
        result.put("msg", "返回json数据");
        return result;
    }
}```