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package com.fasterxml.jackson.databind;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.fasterxml.jackson.databind.cfg.ConfigFeature;
/**
* Enumeration that defines simple on/off features to set
* for {@link ObjectMapper}, and accessible (but not changeable)
* via {@link ObjectReader} and {@link ObjectWriter} (as well as
* through various convenience methods through context objects).
*
* Note that in addition to being only mutable via {@link ObjectMapper},
* changes only take effect when done before any serialization or
* deserialization calls -- that is, caller must follow
* "configure-then-use" pattern.
*/
public enum MapperFeature implements ConfigFeature
{
/*
/******************************************************
/* General introspection features
/******************************************************
*/
/**
* Feature that determines whether annotation introspection
* is used for configuration; if enabled, configured
* {@link AnnotationIntrospector} will be used: if disabled,
* no annotations are considered.
*
* Feature is enabled by default.
*/
USE_ANNOTATIONS(true),
/**
* Feature that determines whether otherwise regular "getter"
* methods (but only ones that handle Collections and Maps,
* not getters of other type)
* can be used for purpose of getting a reference to a Collection
* and Map to modify the property, without requiring a setter
* method.
* This is similar to how JAXB framework sets Collections and
* Maps: no setter is involved, just setter.
*
* Note that such getters-as-setters methods have lower
* precedence than setters, so they are only used if no
* setter is found for the Map/Collection property.
*
* Feature is enabled by default.
*/
USE_GETTERS_AS_SETTERS(true),
/**
* Feature that determines how transient modifier for fields
* is handled: if disabled, it is only taken to mean exclusion of the field
* as accessor; if true, it is taken to imply removal of the whole property.
*
* Feature is disabled by default, meaning that existence of `transient`
* for a field does not necessarily lead to ignoral of getters or setters
* but just ignoring the use of field for access.
*
* @since 2.6
*/
PROPAGATE_TRANSIENT_MARKER(false),
/*
/******************************************************
/* Introspection-based property auto-detection
/******************************************************
*/
/**
* Feature that determines whether "creator" methods are
* automatically detected by consider public constructors,
* and static single argument methods with name "valueOf".
* If disabled, only methods explicitly annotated are considered
* creator methods (except for the no-arg default constructor which
* is always considered a factory method).
*
* Note that this feature has lower precedence than per-class
* annotations, and is only used if there isn't more granular
* configuration available.
*
* Feature is enabled by default.
*/
AUTO_DETECT_CREATORS(true),
/**
* Feature that determines whether non-static fields are recognized as
* properties.
* If yes, then all public member fields
* are considered as properties. If disabled, only fields explicitly
* annotated are considered property fields.
*
* Note that this feature has lower precedence than per-class
* annotations, and is only used if there isn't more granular
* configuration available.
*
* Feature is enabled by default.
*/
AUTO_DETECT_FIELDS(true),
/**
* Feature that determines whether regular "getter" methods are
* automatically detected based on standard Bean naming convention
* or not. If yes, then all public zero-argument methods that
* start with prefix "get"
* are considered as getters.
* If disabled, only methods explicitly annotated are considered getters.
*
* Note that since version 1.3, this does NOT include
* "is getters" (see {@link #AUTO_DETECT_IS_GETTERS} for details)
*
* Note that this feature has lower precedence than per-class
* annotations, and is only used if there isn't more granular
* configuration available.
*
* Feature is enabled by default.
*/
AUTO_DETECT_GETTERS(true),
/**
* Feature that determines whether "is getter" methods are
* automatically detected based on standard Bean naming convention
* or not. If yes, then all public zero-argument methods that
* start with prefix "is", and whose return type is boolean
* are considered as "is getters".
* If disabled, only methods explicitly annotated are considered getters.
*
* Note that this feature has lower precedence than per-class
* annotations, and is only used if there isn't more granular
* configuration available.
*
* Feature is enabled by default.
*/
AUTO_DETECT_IS_GETTERS(true),
/**
* Feature that determines whether "setter" methods are
* automatically detected based on standard Bean naming convention
* or not. If yes, then all public one-argument methods that
* start with prefix "set"
* are considered setters. If disabled, only methods explicitly
* annotated are considered setters.
*
* Note that this feature has lower precedence than per-class
* annotations, and is only used if there isn't more granular
* configuration available.
*
* Feature is enabled by default.
*/
AUTO_DETECT_SETTERS(true),
/**
* Feature that determines whether getters (getter methods)
* can be auto-detected if there is no matching mutator (setter,
* constructor parameter or field) or not: if set to true,
* only getters that match a mutator are auto-discovered; if
* false, all auto-detectable getters can be discovered.
*
* Feature is disabled by default.
*/
REQUIRE_SETTERS_FOR_GETTERS(false),
/**
* Feature that determines whether member fields declared as 'final' may
* be auto-detected to be used mutators (used to change value of the logical
* property) or not. If enabled, 'final' access modifier has no effect, and
* such fields may be detected according to usual visibility and inference
* rules; if disabled, such fields are NOT used as mutators except if
* explicitly annotated for such use.
*
* Feature is enabled by default, for backwards compatibility reasons.
*
* @since 2.2
*/
ALLOW_FINAL_FIELDS_AS_MUTATORS(true),
/**
* Feature that determines whether member mutators (fields and
* setters) may be "pulled in" even if they are not visible,
* as long as there is a visible accessor (getter or field) with same name.
* For example: field "value" may be inferred as mutator,
* if there is visible or explicitly marked getter "getValue()".
* If enabled, inferring is enabled; otherwise (disabled) only visible and
* explicitly annotated accessors are ever used.
*
* Note that 'getters' are never inferred and need to be either visible (including
* bean-style naming) or explicitly annotated.
*
* Feature is enabled by default.
*
* @since 2.2
*/
INFER_PROPERTY_MUTATORS(true),
/**
* Feature that determines handling of java.beans.ConstructorProperties
* annotation: when enabled, it is considered as alias of
* {@link com.fasterxml.jackson.annotation.JsonCreator}, to mean that constructor
* should be considered a property-based Creator; when disabled, only constructor
* parameter name information is used, but constructor is NOT considered an explicit
* Creator (although may be discovered as one using other annotations or heuristics).
*
* Feature is mostly used to help interoperability with frameworks like Lombok
* that may automatically generate ConstructorProperties annotation
* but without necessarily meaning that constructor should be used as Creator
* for deserialization.
*
* Feature is enabled by default.
*
* @since 2.9
*/
INFER_CREATOR_FROM_CONSTRUCTOR_PROPERTIES(true),
/*
/******************************************************
/* Access modifier handling
/******************************************************
*/
/**
* Feature that determines whether method and field access
* modifier settings can be overridden when accessing
* properties. If enabled, method
* {@link java.lang.reflect.AccessibleObject#setAccessible}
* may be called to enable access to otherwise unaccessible objects.
*
* Note that this setting may have significant performance implications,
* since access override helps remove costly access checks on each
* and every Reflection access. If you are considering disabling
* this feature, be sure to verify performance consequences if usage
* is performance sensitive.
* Also note that performance effects vary between Java platforms
* (JavaSE vs Android, for example), as well as JDK versions: older
* versions seemed to have more significant performance difference.
*
* Conversely, on some platforms, it may be necessary to disable this feature
* as platform does not allow such calls. For example, when developing
* Applets (or other Java code that runs on tightly restricted sandbox),
* it may be necessary to disable the feature regardless of performance effects.
*
* Feature is enabled by default.
*/
CAN_OVERRIDE_ACCESS_MODIFIERS(true),
/**
* Feature that determines that forces call to
* {@link java.lang.reflect.AccessibleObject#setAccessible} even for
* public accessors -- that is, even if no such call is
* needed from functionality perspective -- if call is allowed
* (that is, {@link #CAN_OVERRIDE_ACCESS_MODIFIERS} is set to true).
* The main reason to enable this feature is possible performance
* improvement as JDK does not have to perform access checks; these
* checks are otherwise made for all accessors, including public ones,
* and may result in slower Reflection calls. Exact impact (if any)
* depends on Java platform (Java SE, Android) as well as JDK version.
*
* Feature is enabled by default, for legacy reasons (it was the behavior
* until 2.6)
*
* @since 2.7
*/
OVERRIDE_PUBLIC_ACCESS_MODIFIERS(true),
/*
/******************************************************
/* Type-handling features
/******************************************************
*/
/**
* Feature that determines whether the type detection for
* serialization should be using actual dynamic runtime type,
* or declared static type.
* Note that deserialization always uses declared static types
* since no runtime types are available (as we are creating
* instances after using type information).
*
* This global default value can be overridden at class, method
* or field level by using {@link JsonSerialize#typing} annotation
* property.
*
* Feature is disabled by default which means that dynamic runtime types
* are used (instead of declared static types) for serialization.
*/
USE_STATIC_TYPING(false),
/**
* Feature that specifies whether the declared base type of a polymorphic value
* is to be used as the "default" implementation, if no explicit default class
* is specified via {@code @JsonTypeInfo.defaultImpl} annotation.
*
* Note that feature only has effect on deserialization of regular polymorphic properties:
* it does NOT affect non-polymorphic cases, and is unlikely to work with Default Typing.
*
* Feature is disabled by default for backwards compatibility.
*
* @since 2.9.6
*/
USE_BASE_TYPE_AS_DEFAULT_IMPL(false),
/*
/******************************************************
/* View-related features
/******************************************************
*/
/**
* Feature that determines whether properties that have no view
* annotations are included in JSON serialization views (see
* {@link com.fasterxml.jackson.annotation.JsonView} for more
* details on JSON Views).
* If enabled, non-annotated properties will be included;
* when disabled, they will be excluded. So this feature
* changes between "opt-in" (feature disabled) and
* "opt-out" (feature enabled) modes.
*
* Default value is enabled, meaning that non-annotated
* properties are included in all views if there is no
* {@link com.fasterxml.jackson.annotation.JsonView} annotation.
*
* Feature is enabled by default.
*/
DEFAULT_VIEW_INCLUSION(true),
/*
/******************************************************
/* Generic output features
/******************************************************
*/
/**
* Feature that defines default property serialization order used
* for POJO fields (note: does not apply to {@link java.util.Map}
* serialization!):
* if enabled, default ordering is alphabetic (similar to
* how {@link com.fasterxml.jackson.annotation.JsonPropertyOrder#alphabetic()}
* works); if disabled, order is unspecified (based on what JDK gives
* us, which may be declaration order, but is not guaranteed).
*
* Note that this is just the default behavior, and can be overridden by
* explicit overrides in classes (for example with
* {@link com.fasterxml.jackson.annotation.JsonPropertyOrder} annotation)
*
* Feature is disabled by default.
*/
SORT_PROPERTIES_ALPHABETICALLY(false),
/*
/******************************************************
/* Name-related features
/******************************************************
*/
/**
* Feature that will allow for more forgiving deserialization of incoming JSON.
* If enabled, the bean properties will be matched using their lower-case equivalents,
* meaning that any case-combination (incoming and matching names are canonicalized
* by lower-casing) should work.
*
* Note that there is additional performance overhead since incoming property
* names need to be lower-cased before comparison, for cases where there are upper-case
* letters. Overhead for names that are already lower-case should be negligible however.
*
* Feature is disabled by default.
*
* @since 2.5
*/
ACCEPT_CASE_INSENSITIVE_PROPERTIES(false),
/**
* Feature that determines if Enum deserialization should be case sensitive or not.
* If enabled, Enum deserialization will ignore case, that is, case of incoming String
* value and enum id (dependant on other settings, either `name()`, `toString()`, or
* explicit override) do not need to match.
*
* Feature is disabled by default.
*
* @since 2.9
*/
ACCEPT_CASE_INSENSITIVE_ENUMS(false),
/**
* Feature that can be enabled to make property names be
* overridden by wrapper name (usually detected with annotations
* as defined by {@link AnnotationIntrospector#findWrapperName}.
* If enabled, all properties that have associated non-empty Wrapper
* name will use that wrapper name instead of property name.
* If disabled, wrapper name is only used for wrapping (if anything).
*
* Feature is disabled by default.
*
* @since 2.1
*/
USE_WRAPPER_NAME_AS_PROPERTY_NAME(false),
/**
* Feature that may be enabled to enforce strict compatibility with
* Bean name introspection, instead of slightly different mechanism
* Jackson defaults to.
* Specific difference is that Jackson always lower cases leading upper-case
* letters, so "getURL()" becomes "url" property; whereas standard Bean
* naming only lower-cases the first letter if it is NOT followed by
* another upper-case letter (so "getURL()" would result in "URL" property).
*
* Feature is disabled by default for backwards compatibility purposes: earlier
* Jackson versions used Jackson's own mechanism.
*
* @since 2.5
*/
USE_STD_BEAN_NAMING(false),
/**
* Feature that when enabled will allow explicitly named properties (i.e., fields or methods
* annotated with {@link com.fasterxml.jackson.annotation.JsonProperty}("explicitName")) to
* be re-named by a {@link PropertyNamingStrategy}, if one is configured.
*
* Feature is disabled by default.
*
* @since 2.7
*/
ALLOW_EXPLICIT_PROPERTY_RENAMING(false),
/*
/******************************************************
/* Coercion features
/******************************************************
*/
/**
* Feature that determines whether coercions from secondary representations are allowed
* for simple non-textual scalar types: numbers and booleans. This includes `primitive`
* types and their wrappers, but excludes `java.lang.String` and date/time types.
*
* When feature is disabled, only strictly compatible input may be bound: numbers for
* numbers, boolean values for booleans. When feature is enabled, conversions from
* JSON String are allowed, as long as textual value matches (for example, String
* "true" is allowed as equivalent of JSON boolean token `true`; or String "1.0"
* for `double`).
*
* Note that it is possible that other configurability options can override this
* in closer scope (like on per-type or per-property basis); this is just the global
* default.
*
* Feature is enabled by default (for backwards compatibility since this was the
* default behavior)
*
* @since 2.9
*/
ALLOW_COERCION_OF_SCALARS(true),
/*
/******************************************************
/* Other features
/******************************************************
*/
/**
* Feature that determines whether multiple registrations of same module
* should be ignored or not; if enabled, only the first registration call
* results in module being called, and possible duplicate calls are silently
* ignored; if disabled, no checking is done and all registration calls are
* dispatched to module.
*
* Definition of "same module" is based on using {@link Module#getTypeId()};
* modules with same non-null type id are considered same for
* purposes of duplicate registration. This also avoids having to keep track
* of actual module instances; only ids will be kept track of (and only if
* this feature is enabled).
*
* Feature is enabled by default.
*
* @since 2.5
*/
IGNORE_DUPLICATE_MODULE_REGISTRATIONS(true),
/**
* Setting that determines what happens if an attempt is made to explicitly
* "merge" value of a property, where value does not support merging; either
* merging is skipped and new value is created (true) or
* an exception is thrown (false).
*
* Feature is disabled by default since non-mergeable property types are ignored
* even if defaults call for merging, and usually explicit per-type or per-property
* settings for such types should result in an exception.
*
* @since 2.9
*/
IGNORE_MERGE_FOR_UNMERGEABLE(true)
;
private final boolean _defaultState;
private final int _mask;
private MapperFeature(boolean defaultState) {
_defaultState = defaultState;
_mask = (1 << ordinal());
}
@Override
public boolean enabledByDefault() { return _defaultState; }
@Override
public int getMask() { return _mask; }
@Override
public boolean enabledIn(int flags) { return (flags & _mask) != 0; }
}