【SpringBoot】统一功能处理

目录

拦截器

统一结果返回

统一异常处理

拦截器

package com.example.demo.config;

import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;


@Component
public class LoginInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        return true;
    }
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        //拦截到请求后，具体处理逻辑
    }
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        //视图渲染完毕后执⾏，最后执⾏
    }
}

package com.example.demo.config;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class WebConfig implements WebMvcConfigurer {
    //⾃定义的拦截器对象
    @Autowired
    private LoginInterceptor loginInterceptor;
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //注册⾃定义拦截器对象
        registry.addInterceptor(loginInterceptor)
                .addPathPatterns("/**");//设置拦截器拦截的请求路径（ /** 表⽰拦截所有请求）
    }
}

统一结果返回

package com.example.demo.config;

import lombok.Data;

@Data
public class Result<T> {
    private T data;
}

package com.example.demo.config;

import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.SneakyThrows;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.MethodParameter;
import org.springframework.http.MediaType;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;



@ControllerAdvice
public class ResponseAdvice implements ResponseBodyAdvice {
    @Autowired
    private ObjectMapper objectMapper;
    @Override
    public boolean supports(MethodParameter returnType, Class converterType) {
        return true;
    }
    @SneakyThrows
    @Override
    public Object beforeBodyWrite(Object body, MethodParameter returnType, MediaType selectedContentType, Class selectedConverterType, ServerHttpRequest request, ServerHttpResponse response) {
        Result<Object> ret = new Result<>();
        ret.setData(body);
        //返回结果更加灵活
        if (body instanceof Result){ return body;}
        //如果返回结果为String类型, 使⽤SpringBoot内置提供的Jackson来实现信息的序列化
        if (body instanceof String){ return objectMapper.writeValueAsString(ret); }
        //返回统一格式
        return ret;
    }
}

统一异常处理

package com.example.demo.config;

import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;

@ControllerAdvice
@ResponseBody
public class ErrorAdvice {
    @ExceptionHandler
    public Object handler(Exception e) { return e.getMessage(); }
}