统一配置的开发

http的消息转化器，将java的对象转换成http的输出流

1.首先定义一个包

2.编写实现消息转换器的类

package com.imooc.ad.conf;

import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.util.List;

@Configuration
public class WebConfiguration implements WebMvcConfigurer {
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        converters.clear();
        converters.add(new MappingJackson2HttpMessageConverter());
    }
}