场景：
在做接口时，有的时候，接口入参只需要一个参数，如果将一个参数封装成一个对象很麻烦，故有了以下方式：
思路：
spring自带的参数解析器貌似是不具备这个能力的，所有自定义
方式方法：
1.定义一个注解
@Target(ElementType.PARAMETER)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface RequestSingleParam {
String value(); boolean required() default true; String defaultValue() default "";
}
2.定义解析器
public class RequestSingleParamHandlerMethodArgumentResolver implements HandlerMethodArgumentResolver {
@Override
public boolean supportsParameter(MethodParameter parameter) {
return parameter.hasParameterAnnotation(RequestSingleParam.class);
}
@Override
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
RequestSingleParam requestSingleParam = parameter.getParameterAnnotation(RequestSingleParam.class);
HttpServletRequest request = webRequest.getNativeRequest(HttpServletRequest.class);
BufferedReader reader = request.getReader();
StringBuilder sb = new StringBuilder();
char[] buf = new char[];
int rd;
while ((rd = reader.read(buf)) != -) {
sb.append(buf, , rd);
}
JSONObject jsonObject = JSONObject.parseObject(sb.toString());
String value = requestSingleParam.value();
return jsonObject.get(value);
}
}
3.修改Springboot启动类(a.继承WebMvcConfigurerAdapter；b.重写addArgumentResolvers()方法)
@SpringBootApplication
@EnableWebMvc
public class SpringbootDemoApplication extends WebMvcConfigurerAdapter { public static void main(String[] args) {
SpringApplication.run(SpringbootDemoApplication.class, args);
} @Override
public void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers){
argumentResolvers.add(new RequestSingleParamHandlerMethodArgumentResolver());
super.addArgumentResolvers(argumentResolvers);
}
}
4.在Controller中应用
调用接口方，传参如： {“name”:"张三"}，Controller中就能获取到"张三”
@RequestMapping(value = "/test",method = RequestMethod.POST)
public void test(@RequestSingleParam(value = "name") String name){
System.out.println(name);
}