请求参数的自定义 Spring 注解
Custom Spring annotation for request parameters
我想写自定义注解,根据注解修改Spring请求或路径参数。例如代替此代码:
@RequestMapping(method = RequestMethod.GET)
public String test(@RequestParam("title") String text) {
text = text.toUpperCase();
System.out.println(text);
return "form";
}
我可以做注解@UpperCase :
@RequestMapping(method = RequestMethod.GET)
public String test(@RequestParam("title") @UpperCase String text) {
System.out.println(text);
return "form";
}
这可能吗?如果可能,我该怎么做?
正如大家在评论中所说,您可以轻松编写注释驱动的自定义解析器。四个简单的步骤,
- 创建注释,例如
@Target(ElementType.PARAMETER)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface UpperCase {
String value();
}
- 写一个解析器,例如
public class UpperCaseResolver implements HandlerMethodArgumentResolver {
public boolean supportsParameter(MethodParameter parameter) {
return parameter.getParameterAnnotation(UpperCase.class) != null;
}
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer, NativeWebRequest webRequest,
WebDataBinderFactory binderFactory) throws Exception {
UpperCase attr = parameter.getParameterAnnotation(UpperCase.class);
return webRequest.getParameter(attr.value()).toUpperCase();
}
}
- 注册解析器
<mvc:annotation-driven>
<mvc:argument-resolvers>
<bean class="your.package.UpperCaseResolver"></bean>
</mvc:argument-resolvers>
</mvc:annotation-driven>
或 java 配置
@Configuration
@EnableWebMvc
public class Config extends WebMvcConfigurerAdapter {
...
@Override
public void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) {
argumentResolvers.add(new UpperCaseResolver());
}
...
}
- 在控制器方法中使用注解,例如
public String test(@UpperCase("foo") String foo)
我想写自定义注解,根据注解修改Spring请求或路径参数。例如代替此代码:
@RequestMapping(method = RequestMethod.GET)
public String test(@RequestParam("title") String text) {
text = text.toUpperCase();
System.out.println(text);
return "form";
}
我可以做注解@UpperCase :
@RequestMapping(method = RequestMethod.GET)
public String test(@RequestParam("title") @UpperCase String text) {
System.out.println(text);
return "form";
}
这可能吗?如果可能,我该怎么做?
正如大家在评论中所说,您可以轻松编写注释驱动的自定义解析器。四个简单的步骤,
- 创建注释,例如
@Target(ElementType.PARAMETER)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface UpperCase {
String value();
}
- 写一个解析器,例如
public class UpperCaseResolver implements HandlerMethodArgumentResolver {
public boolean supportsParameter(MethodParameter parameter) {
return parameter.getParameterAnnotation(UpperCase.class) != null;
}
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer, NativeWebRequest webRequest,
WebDataBinderFactory binderFactory) throws Exception {
UpperCase attr = parameter.getParameterAnnotation(UpperCase.class);
return webRequest.getParameter(attr.value()).toUpperCase();
}
}
- 注册解析器
<mvc:annotation-driven>
<mvc:argument-resolvers>
<bean class="your.package.UpperCaseResolver"></bean>
</mvc:argument-resolvers>
</mvc:annotation-driven>
或 java 配置
@Configuration
@EnableWebMvc
public class Config extends WebMvcConfigurerAdapter {
...
@Override
public void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) {
argumentResolvers.add(new UpperCaseResolver());
}
...
}
- 在控制器方法中使用注解,例如
public String test(@UpperCase("foo") String foo)