使用 java-configuration 配置 MappingJackson2HttpMessageConverter

Question

我正在尝试配置MappingJackson2HttpMessageConverter，因为我想禁用WRITE_DATES_TO_TIMESTAMP功能。

如果我通过 xml 配置它，它可以成功工作

<bean name="jacksonObjectMapper"
    class="org.springframework.http.converter.json.Jackson2ObjectMapperFactoryBean">
    <property name="featuresToDisable">
        <array>
            <util:constant
                static-field="com.fasterxml.jackson.databind.SerializationFeature.WRITE_DATES_AS_TIMESTAMPS" />
        </array>
    </property>
</bean>
<mvc:annotation-driven>
    <mvc:message-converters register-defaults="true">
        <bean
            class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
            <property name="objectMapper" ref="jacksonObjectMapper" />
        </bean>
    </mvc:message-converters>
</mvc:annotation-driven>

但是当我尝试通过 java 配置进行配置时，转换器已注册，但序列化忽略了映射器的配置。

我尝试过不同的方法。

方法1

@Configuration
@EnableWebMvc
public class WebConfig extends WebMvcConfigurerAdapter {
@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
    ObjectMapper mapper = new ObjectMapper();
    mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
    converters.add(new MappingJackson2HttpMessageConverter(mapper));
}
}

方法2

@Configuration
@EnableWebMvc
public class WebConfig extends WebMvcConfigurerAdapter {
@Override
public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
    for (HttpMessageConverter<?> converter : converters) {
        if (converter instanceof MappingJackson2HttpMessageConverter) {
        MappingJackson2HttpMessageConverter jacksonMessageConverter = (MappingJackson2HttpMessageConverter) converter;
        ObjectMapper objectMapper = jacksonMessageConverter.getObjectMapper();
        objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        break;
        }
    }
}
}

Answer 1

尝试以下方法：

@Configuration
@EnableWebMvc
public class WebConfig extends WebMvcConfigurerAdapter {
    ...
    @Override
    public void configureMessageConverters(
        List<HttpMessageConverter<?>> converters) {
        Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
        builder.dateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm"));
        builder.featuresToDisable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        converters.add(new MappingJackson2HttpMessageConverter(builder.build()));
    }
    ...
}

Answer 2

也许你在 xml 中还有注释驱动？

它还注册默认的消息转换器和对象映射器。

Answer 3

这也对我有用

@Bean
public Jackson2ObjectMapperBuilder jackson2ObjectMapperBuilder() {
    Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
    builder.featuresToDisable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
    return builder;
}

Answer 4

试试这个：

@Configuration
@EnableWebMvc
@ComponentScan
public class MvcConfig implements WebMvcConfigurer {
    @Bean
    public MappingJackson2HttpMessageConverter jsonConverter() {
    List<MediaType> supportedMediaTypes = new ArrayList<>();
    supportedMediaTypes.add(MediaType.APPLICATION_JSON);
    Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
    builder.serializationInclusion(JsonInclude.Include.NON_NULL);
    MappingJackson2HttpMessageConverter jsonConverter = new MappingJackson2HttpMessageConverter(builder.build());
    jsonConverter.setSupportedMediaTypes(supportedMediaTypes);
    return jsonConverter;
}
@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
    converters.add(new StringHttpMessageConverter());
    converters.add(jsonConverter());
}
}