如何在Spring Boot 1.4中自定义Jackson

小编典典

如何在Spring Boot 1.4中自定义Jackson

spring-boot

我一直找不到如何在Spring Boot 1.4中使用 Jackson2ObjectMapperBuilderCustomizer.java
来自定义Jackson功能的示例。

在启动1.4定制杰克逊DOCO - http://docs.spring.io/spring-boot/docs/current-
SNAPSHOT/reference/htmlsingle/#howto-customize-the-
jackson-

我的配置有效，尽管我不确定这是否是使用 Jackson2ObjectMapperBuilderCustomizer.java 定制对象映射器的正确方法。
__

@Configuration
public class JacksonAutoConfiguration {

    @Autowired
    private Environment env;

    @Bean
    public Jackson2ObjectMapperBuilder jacksonObjectMapperBuilder(
        List<Jackson2ObjectMapperBuilderCustomizer> customizers) {
        Jackson2ObjectMapperBuilder builder = configureObjectMapper();
        customize(builder, customizers);
        return builder;
    }

    private void customize(Jackson2ObjectMapperBuilder builder,
                           List<Jackson2ObjectMapperBuilderCustomizer> customizers) {
        for (Jackson2ObjectMapperBuilderCustomizer customizer : customizers) {
            customizer.customize(builder);
        }
    }

    private Jackson2ObjectMapperBuilder configureObjectMapper() {
        Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
        List<String> activeProfiles = asList(env.getActiveProfiles());
        if (activeProfiles.contains(SPRING_PROFILE_DEVELOPMENT)) {
            builder.featuresToEnable(SerializationFeature.INDENT_OUTPUT);
        }
        return builder;
    }
}

为了提供一些上下文，该类位于我自己的REST服务的spring
starter项目中，该项目仅自动配置许多东西，例如ControllerAdvice和上述的一些琐碎功能。

因此，我的目标是扩展Jackson配置，而不是覆盖启动程序或其他软件包提供的任何配置。

阅读 378

2020-05-30

共1个答案

小编典典

为了自定义ObjectMapperSpring Boot已经预先配置的Jackson ，我能够做到这一点（这里的示例是添加一个自定义解串器）。

配置类：

@SpringBootConfiguration
public class Application {

    @Autowired
    private BigDecimalDeserializer bigDecimalDeserializer;

    ...

    @Bean
    public Jackson2ObjectMapperBuilderCustomizer addCustomBigDecimalDeserialization() {
        return new Jackson2ObjectMapperBuilderCustomizer() {

            @Override
            public void customize(Jackson2ObjectMapperBuilder jacksonObjectMapperBuilder) {
                jacksonObjectMapperBuilder.deserializerByType(BigDecimal.class, bigDecimalDeserializer);
            }

        };
    }

    ...

}

还有我的自定义反序列化器，以显示Spring如何拾取它：

@Component
public class BigDecimalDeserializer extends StdDeserializer<BigDecimal> {

    public BigDecimalDeserializer() {
        super(BigDecimal.class);
    }

    @Override
    public BigDecimal deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
        ...
    }

    ...

}

2020-05-30