com.fasterxml.jackson.annotation

Enum JsonInclude.Include

java.lang.Object

java.lang.Enum<JsonInclude.Include>

com.fasterxml.jackson.annotation.JsonInclude.Include

All Implemented Interfaces:

Serializable, Comparable<JsonInclude.Include>

Enclosing class:

JsonInclude

public static enum JsonInclude.Include
extends Enum<JsonInclude.Include>

Enumeration used with JsonInclude to define which properties of Java Beans are to be included in serialization.

Enum Constant Summary

Enum Constants

Enum Constant and Description
ALWAYS Value that indicates that property is to be always included, independent of value of the property.
NON_ABSENT Value that indicates that properties are included unless their value is: null "absent" value of a referential type (like Java 8 `Optional`, or {link java.utl.concurrent.atomic.AtomicReference}); that is, something that would not deference to a non-null value.
NON_DEFAULT Meaning of this setting depends on context: whether annotation is specified for POJO type (class), or not.
NON_EMPTY Value that indicates that only properties with null value, or what is considered empty, are not to be included.
NON_NULL Value that indicates that only properties with non-null values are to be included.
USE_DEFAULTS Pseudo-value used to indicate that the higher-level defaults make sense, to avoid overriding inclusion value.

Method Summary

Methods

Modifier and Type	Method and Description
static JsonInclude.Include	valueOf(String name) Returns the enum constant of this type with the specified name.
static JsonInclude.Include[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

ALWAYS

public static final JsonInclude.Include ALWAYS

Value that indicates that property is to be always included, independent of value of the property.

NON_NULL

public static final JsonInclude.Include NON_NULL

Value that indicates that only properties with non-null values are to be included.

NON_ABSENT

public static final JsonInclude.Include NON_ABSENT

Value that indicates that properties are included unless their value is:

• null
• "absent" value of a referential type (like Java 8 `Optional`, or {link java.utl.concurrent.atomic.AtomicReference}); that is, something that would not deference to a non-null value.

This option is mostly used to work with "Optional"s (Java 8, Guava).

Since:

2.6

NON_EMPTY

public static final JsonInclude.Include NON_EMPTY

Value that indicates that only properties with null value, or what is considered empty, are not to be included. Definition of emptiness is data type specific; see below for details on actual handling.

Default emptiness for all types includes:

• Null values.
• "Absent" values (see NON_ABSENT)

so that as baseline, "empty" set includes values that would be excluded by both NON_NULL and NON_ABSENT.
Additionally following types have additional empty values:

• For Collections and Maps, method isEmpty() is called;
• For Java arrays, empty arrays are ones with length of 0
• For Java Strings, length() is called, and return value of 0 indicates empty String (note that String.isEmpty() was added in Java 1.6 and as such can not be used by Jackson

and for other types, null values are excluded but other exclusions (if any).

Note that this default handling can be overridden by custom JsonSerializer implementation: if method isEmpty() is overridden, it will be called to see if non-null values are considered empty (null is always considered empty).

Compatibility note: Jackson 2.6 included a wider range of "empty" values than either earlier (up to 2.5) or later (2.7 and beyond) types; specifically:

• Default values of primitive types (like 0 for `int`/`java.lang.Integer` and `false` for `bool`/`Boolean`)
• Timestamp 0 for date/time types

With 2.7, definition has been tightened back to only containing types explained above (null, absent, empty String, empty containers), and now extended definition may be specified using NON_DEFAULT.

NON_DEFAULT

public static final JsonInclude.Include NON_DEFAULT

Meaning of this setting depends on context: whether annotation is specified for POJO type (class), or not. In latter case annotation is either used as the global default, or as property override.

When used for a POJO, definition is that only values that differ from the default values of POJO properties are included. This is done by creating an instance of POJO using zero-argument constructor, and accessing property values: value is used as the default value by using equals() method, except for the case where property has `null` value in which straight null check is used.

When NOT used for a POJO (that is, as a global default, or as property override), definition is such that:

• All values considered "empty" (as per NON_EMPTY) are excluded
• Primitive/wrapper default values are excluded
• Date/time values that have timestamp (`long` value of milliseconds since epoch, see Date) of `0L` are excluded

USE_DEFAULTS

public static final JsonInclude.Include USE_DEFAULTS

Pseudo-value used to indicate that the higher-level defaults make sense, to avoid overriding inclusion value. For example, if returned for a property this would use defaults for the class that contains property, if any defined; and if none defined for that, then global serialization inclusion details.

Since:

2.6

Method Detail

values

public static JsonInclude.Include[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (JsonInclude.Include c : JsonInclude.Include.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static JsonInclude.Include valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null