Jackson Ignore Properties on Marshalling
In this section, we will understand how we can ignore the fields at the time of serializing an object into JSON. There are various ways to ignore the properties which we use when Jackson defaults are not enough to control what gets serialized to JSON.
Ignore fields at the class level
At the class level, we can easily ignore the specific fields by using the @JsonIgnoreProperties and specifying the fields by name. Let's take an example to understand how we use this annotation to ignore fields at the class level.
Ignore fields at the field level
At the field level, we can directly ignore the field with the help of the @JsonIgnore. Let's take an example to understand how we use this annotation to ignore fields at the field level.
Ignore all fields by type
In this way, we ignore all the fields of a specified type. We can directly annotate the class if we can control the type.
All the time, however, we don't have control of the class itself, so we can use Jackson mixins too. We use the following steps to use mixins:
1. Define mixin for the type we would like to ignore.
2. Annotate mixin with @JsonIgnoreType annotation.
3. Register mixin for ignoring all Address types during marshalling.
Let's take an example to understand how we can use mixin to ignore fields of Address type.
Ignore fields by using filters
By using the filters, we can also ignore the specific fields in Jackson. In order to use the filter, we need to define it on the Java object in the following way:
After that, we define a simple filter to ignore the intValue field:
Let's take an example to understand how we can use a filter to ignore the intValue field.