Ignore operations that are null properties when serializing entity classes or objects

First, configure in the configuration file

Direct configuration in application. xml, which is global configuration, and all attributes returned to front-end objects as null or "" are not serialized;

spring: 
  jackson:
    # Entity class conversion json When the field is null Do not participate in serialization 
    default-property-inclusion: NON_EMPTY

Four Types of default-property-inclusion

ALWAYS Default The NON_DEFAULT attribute is not serialized for the default value NON_EMPTY attribute "" or NULL is not serialized No serialization when NON_NULL attribute is NULL

Second, set each class separately

Add @ JsonInclude (Include.NON_NULL) to the object attribute that needs to ignore serialization when it is empty, or directly add it to the class, indicating that 1 does not participate in serialization when the attribute of the whole object is null;

You can set different types in @ JsonInclude parentheses

Include. Include. ALWAYS Default The Include. NON_DEFAULT property is not serialized by default Include. NON_EMPTY attribute "" or NULL is not serialized Include. NON_NULL is not serialized when the attribute is NULL

If the global is configured and an object is annotated, the annotation overrides the global setting.

SpringBoot2. x does not reverse null value attributes

Sometimes, there is no value of the attribute in the data we return, or the value of the attribute is a blank string, which will waste network traffic, or the bug existing in the front-end framework will cause the null value or the blank string to report errors when rendering.

Treatment mode

Type 1

Global way: Add the following attributes to the configuration file of SpringBoot to achieve global filtering

spring.jackson.default-property-inclusion=non_empty

Type 2

Local way: Add the following annotations to the returned entity class attributes or class names to achieve the filtering effect

@JsonInclude(JsonInclude.Include.NON_EMPTY)

Attention

This is also true for empty collections. Attribute 1 has the following optional values

Include. Include. ALWAYS Default The Include. NON_DEFAULT property is not serialized by default Include. NON_EMPTY property is null ("") or NULL is not serialized Include. NON_NULL property is NULL not serialized