org.springframework.http.codec.json

Class Jackson2CodecSupport

java.lang.Object

org.springframework.http.codec.json.Jackson2CodecSupport

Direct Known Subclasses:

AbstractJackson2Decoder, AbstractJackson2Encoder

public abstract class Jackson2CodecSupport
extends Object

Base class providing support methods for Jackson 2.9 encoding and decoding.

Since:

5.0

Author:

Sebastien Deleuze, Rossen Stoyanchev

Field Summary

Fields

Modifier and Type	Field and Description
static String	JSON_VIEW_HINT The key for the hint to specify a "JSON View" for encoding or decoding with the value expected to be a Class.
protected Log	logger

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Jackson2CodecSupport(ObjectMapper objectMapper, MimeType... mimeTypes) Constructor with a Jackson ObjectMapper to use.

Method Summary

Modifier and Type	Method and Description
protected abstract <A extends Annotation> A	getAnnotation(MethodParameter parameter, Class<A> annotType)
protected Map<String,Object>	getHints(ResolvableType resolvableType)
protected JavaType	getJavaType(Type type, Class<?> contextClass)
protected List<MimeType>	getMimeTypes() Subclasses should expose this as "decodable" or "encodable" mime types.
protected List<MimeType>	getMimeTypes(ResolvableType elementType)
ObjectMapper	getObjectMapper() Return the configured default ObjectMapper.
protected Map<Class<?>,Map<MimeType,ObjectMapper>>	getObjectMapperRegistrations()
Map<MimeType,ObjectMapper>	getObjectMappersForType(Class<?> clazz) Return ObjectMapper registrations for the given class, if any.
protected MethodParameter	getParameter(ResolvableType type)
protected void	logWarningIfNecessary(Type type, Throwable cause) Determine whether to log the given exception coming from a ObjectMapper.canDeserialize(com.fasterxml.jackson.databind.JavaType) / ObjectMapper.canSerialize(java.lang.Class<?>) check.
void	registerObjectMappersForType(Class<?> clazz, Consumer<Map<MimeType,ObjectMapper>> registrar) Configure the ObjectMapper instances to use for the given Class.
protected ObjectMapper	selectObjectMapper(ResolvableType targetType, MimeType targetMimeType) Select an ObjectMapper to use, either the main ObjectMapper or another if the handling for the given Class has been customized through registerObjectMappersForType(Class, Consumer).
void	setObjectMapper(ObjectMapper objectMapper) Configure the default ObjectMapper instance to use.
protected boolean	supportsMimeType(MimeType mimeType)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

JSON_VIEW_HINT

public static final String JSON_VIEW_HINT

The key for the hint to specify a "JSON View" for encoding or decoding with the value expected to be a Class.

See Also:

Jackson JSON Views

logger

protected final Log logger

Constructor Detail

Jackson2CodecSupport

protected Jackson2CodecSupport(ObjectMapper objectMapper,
                               MimeType... mimeTypes)

Constructor with a Jackson ObjectMapper to use.

Method Detail

setObjectMapper

public void setObjectMapper(ObjectMapper objectMapper)

Configure the default ObjectMapper instance to use.

Parameters:

objectMapper - the ObjectMapper instance

Since:

5.3.4

getObjectMapper

public ObjectMapper getObjectMapper()

Return the configured default ObjectMapper.

registerObjectMappersForType

public void registerObjectMappersForType(Class<?> clazz,
                                         Consumer<Map<MimeType,ObjectMapper>> registrar)

Configure the ObjectMapper instances to use for the given Class. This is useful when you want to deviate from the default ObjectMapper or have the ObjectMapper vary by MediaType.

Note: Use of this method effectively turns off use of the default ObjectMapper and supported MimeTypes for the given class. Therefore it is important for the mappings configured here to include every MediaType that must be supported for the given class.

Parameters:

clazz - the type of Object to register ObjectMapper instances for

registrar - a consumer to populate or otherwise update the MediaType-to-ObjectMapper associations for the given Class

Since:

5.3.4

getObjectMappersForType

@Nullable
public Map<MimeType,ObjectMapper> getObjectMappersForType(Class<?> clazz)

Return ObjectMapper registrations for the given class, if any.

Parameters:

clazz - the class to look up for registrations for

Returns:

a map with registered MediaType-to-ObjectMapper registrations, or empty if in case of no registrations for the given class.

Since:

5.3.4

getObjectMapperRegistrations

protected Map<Class<?>,Map<MimeType,ObjectMapper>> getObjectMapperRegistrations()

getMimeTypes

protected List<MimeType> getMimeTypes()

Subclasses should expose this as "decodable" or "encodable" mime types.

getMimeTypes

protected List<MimeType> getMimeTypes(ResolvableType elementType)

supportsMimeType

protected boolean supportsMimeType(@Nullable
                                   MimeType mimeType)

logWarningIfNecessary

protected void logWarningIfNecessary(Type type,
                                     @Nullable
                                     Throwable cause)

Determine whether to log the given exception coming from a ObjectMapper.canDeserialize(com.fasterxml.jackson.databind.JavaType) / ObjectMapper.canSerialize(java.lang.Class<?>) check.

Parameters:

type - the class that Jackson tested for (de-)serializability

cause - the Jackson-thrown exception to evaluate (typically a JsonMappingException)

Since:

5.3.1

getJavaType

protected JavaType getJavaType(Type type,
                               @Nullable
                               Class<?> contextClass)

getHints

protected Map<String,Object> getHints(ResolvableType resolvableType)

getParameter

@Nullable
protected MethodParameter getParameter(ResolvableType type)

getAnnotation

@Nullable
protected abstract <A extends Annotation> A getAnnotation(MethodParameter parameter,
                                                                    Class<A> annotType)

selectObjectMapper

@Nullable
protected ObjectMapper selectObjectMapper(ResolvableType targetType,
                                                    @Nullable
                                                    MimeType targetMimeType)

Select an ObjectMapper to use, either the main ObjectMapper or another if the handling for the given Class has been customized through registerObjectMappersForType(Class, Consumer).

Since:

5.3.4