feign 序列化_Spring Cloud Feign 配置 FastJson

要在Spring Cloud Feign中配置FastJson序列化，您需要完成以下步骤：

1. 添加FastJson依赖

在项目的pom.xml文件中，添加FastJson依赖：

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.47</version>
</dependency>

2. 创建FastJson转换器

创建一个FastJson转换器类，继承自Spring的HttpMessageConverter接口，并实现其方法。代码如下：

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.parser.Feature;
import com.alibaba.fastjson.serializer.SerializerFeature;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpInputMessage;
import org.springframework.http.HttpOutputMessage;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Type;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;

public class FastJsonHttpMessageConverter implements HttpMessageConverter<Object> {

    public static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8");

    private SerializerFeature[] serializerFeatures = new SerializerFeature[0];
    private Feature[] parserFeatures = new Feature[0];

    @Override
    public boolean canRead(Type type, Class<?> contextClass, MediaType mediaType) {
        return true;
    }

    @Override
    public boolean canWrite(Type type, Class<?> aClass, MediaType mediaType) {
        return true;
    }

    @Override
    public List<MediaType> getSupportedMediaTypes() {
        List<MediaType> mediaTypes = new ArrayList<>();
        mediaTypes.add(MediaType.APPLICATION_JSON_UTF8);
        mediaTypes.add(MediaType.APPLICATION_JSON);
        mediaTypes.add(MediaType.TEXT_PLAIN);
        return mediaTypes;
    }

    @Override
    public Object read(Type type, Class<?> contextClass, HttpInputMessage inputMessage) throws IOException {
        InputStream inputStream = inputMessage.getBody();
        return JSON.parseObject(inputStream, DEFAULT_CHARSET, type, parserFeatures);
    }

    @Override
    public void write(Object o, Type type, MediaType mediaType, HttpOutputMessage outputMessage) throws IOException {
        HttpHeaders headers = outputMessage.getHeaders();
        headers.setContentType(MediaType.APPLICATION_JSON_UTF8);
        String jsonString = JSON.toJSONString(o, serializerFeatures);
        OutputStream outputStream = outputMessage.getBody();
        outputStream.write(jsonString.getBytes(DEFAULT_CHARSET));
        outputStream.flush();
    }

    public SerializerFeature[] getSerializerFeatures() {
        return serializerFeatures;
    }

    public void setSerializerFeatures(SerializerFeature[] serializerFeatures) {
        this.serializerFeatures = serializerFeatures;
    }

    public Feature[] getParserFeatures() {
        return parserFeatures;
    }

    public void setParserFeatures(Feature[] parserFeatures) {
        this.parserFeatures = parserFeatures;
    }
}

3. 配置FastJson转换器

在Spring的配置类中，创建一个FastJson转换器的bean，并将其注册到Spring的HttpMessageConverters中。代码如下：

import com.alibaba.fastjson.serializer.SerializerFeature;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.client.RestTemplate;

import java.util.ArrayList;
import java.util.List;

@Configuration
public class FeignConfiguration {

    @Bean
    public HttpMessageConverter fastJsonHttpMessageConverter() {
        return new FastJsonHttpMessageConverter();
    }

    @Bean
    public RestTemplate restTemplate() {
        RestTemplate restTemplate = new RestTemplate();
        List<HttpMessageConverter<?>> messageConverters = new ArrayList<>();
        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        converter.setObjectMapper(new ObjectMapper());
        messageConverters.add(converter);
        messageConverters.add(fastJsonHttpMessageConverter());
        restTemplate.setMessageConverters(messageConverters);
        return restTemplate;
    }
}

4. 配置Feign Client

在Feign Client的配置类中，使用@FeignClient注解的configuration属性，将FastJson转换器的bean引入到Feign Client中。代码如下：

import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
@EnableFeignClients(defaultConfiguration = {FeignConfiguration.class})
public class FeignClientConfiguration {
}

完成以上步骤之后，您就可以在Spring Cloud Feign中使用FastJson作为序列化工具了。