Springboot统一配置Jackson

经常要为接口响应对象设置属性，序列化的时候是不是包含空值，反序列化的时候是否忽略不认识的字段。所以，必须要手动制定ObjectMapper或者在类上声明

@JsonInclude(Include.NON_NULL)
@JsonIgnoreProperties(ignoreUnknown = true)

虽然不算复杂，但既然统一了规则，那就来个统一设定吧。

在springboo1.5+以上的版本可以这么设置Jackson的一些属性配置

spring:
  jackson:
    serialization:
      WRITE_DATES_AS_TIMESTAMPS: false
    default-property-inclusion: non_null

更多配置参见 org.springframework.boot.autoconfigure.jackson.JacksonProperties

@ConfigurationProperties(
    prefix = "spring.jackson"
)
public class JacksonProperties {
    private String dateFormat;
    private String jodaDateTimeFormat;
    private String propertyNamingStrategy;
    private Map<SerializationFeature, Boolean> serialization = new HashMap();
    private Map<DeserializationFeature, Boolean> deserialization = new HashMap();
    private Map<MapperFeature, Boolean> mapper = new HashMap();
    private Map<Feature, Boolean> parser = new HashMap();
    private Map<com.fasterxml.jackson.core.JsonGenerator.Feature, Boolean> generator = new HashMap();
    private Include defaultPropertyInclusion;
    private TimeZone timeZone = null;
    private Locale locale;
    
    //省略
}