在Spring Boot中自定义序列化的方法是实现org.springframework.core.serializer.Serializer接口或org.springframework.core.serializer.SmartSerializer接口。
Serializer接口,需要实现serialize(Object object, OutputStream outputStream)方法,该方法负责将对象序列化为字节数组并写入输出流。如果选择实现SmartSerializer接口,除了实现serialize方法外,还需要实现boolean canSerialize(Class<?> clazz, MediaType mediaType)方法,该方法用于判断是否可以对指定的类进行序列化。在自定义序列化方法后,可以通过在Spring Boot的配置类中使用@Bean注解将自定义的序列化器注入到Spring容器中,并通过配置文件配置使用该序列化器。
例如,使用Jackson库自定义JSON序列化的示例代码如下:
import org.springframework.core.serializer.Serializer;import com.fasterxml.jackson.databind.ObjectMapper;public class JacksonJsonSerializer implements Serializer<Object> { private final ObjectMapper objectMapper; public JacksonJsonSerializer() { this.objectMapper = new ObjectMapper(); } @Override public void serialize(Object object, OutputStream outputStream) throws IOException { objectMapper.writeValue(outputStream, object); }}然后,在Spring Boot的配置类中将该序列化器注入到Spring容器中:
import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;@Configurationpublic class MyConfig { @Bean public JacksonJsonSerializer jacksonJsonSerializer() { return new JacksonJsonSerializer(); } @Bean public MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverter(JacksonJsonSerializer serializer) { MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter(); converter.setObjectMapper(serializer.objectMapper); return converter; }}最后,在配置文件中配置使用自定义的序列化器:
spring.http.converters.preferred-json-mapper=jacksonJsonSerializer 
