程序包 cn.taketoday.http.converter.json

类 AbstractJackson2HttpMessageConverter

java.lang.Object

cn.taketoday.http.converter.AbstractHttpMessageConverter<T>

cn.taketoday.http.converter.AbstractGenericHttpMessageConverter<Object>

cn.taketoday.http.converter.json.AbstractJackson2HttpMessageConverter

所有已实现的接口:

GenericHttpMessageConverter<Object>, HttpMessageConverter<Object>

直接已知子类:

MappingJackson2CborHttpMessageConverter, MappingJackson2HttpMessageConverter, MappingJackson2SmileHttpMessageConverter, MappingJackson2XmlHttpMessageConverter

public abstract class AbstractJackson2HttpMessageConverter
extends AbstractGenericHttpMessageConverter<Object>

Abstract base class for Jackson based and content type independent HttpMessageConverter implementations.

Compatible with Jackson 2.9 to 2.12.

从以下版本开始:

4.0

作者:

Arjen Poutsma, Keith Donald, Rossen Stoyanchev, Juergen Hoeller, Sebastien Deleuze, Sam Brannen, Harry Yang

另请参阅:

• MappingJackson2HttpMessageConverter

字段概要

字段

修饰符和类型	字段	说明
protected ObjectMapper	defaultObjectMapper
private static final HashMap<String,JsonEncoding>	ENCODINGS
private Map<Class<?>,Map<MediaType,ObjectMapper>>	objectMapperRegistrations
private Boolean	prettyPrint
private final PrettyPrinter	ssePrettyPrinter

从类继承的字段 cn.taketoday.http.converter.AbstractHttpMessageConverter

logger

构造器概要

构造器

限定符	构造器	说明
protected	AbstractJackson2HttpMessageConverter(ObjectMapper objectMapper)
protected	AbstractJackson2HttpMessageConverter(ObjectMapper objectMapper, MediaType supportedMediaType)
protected	AbstractJackson2HttpMessageConverter(ObjectMapper objectMapper, MediaType... supportedMediaTypes)

方法概要

修饰符和类型	方法	说明
boolean	canRead(Class<?> clazz, MediaType mediaType)	This implementation checks if the given class is supported, and if the supported media types include the given media type.
boolean	canRead(Type type, Class<?> contextClass, MediaType mediaType)	Indicates whether the given type can be read by this converter.
boolean	canWrite(Class<?> clazz, MediaType mediaType)	This implementation checks if the given class is supported, and if the supported media types include the given media type.
private void	configurePrettyPrint()
protected ObjectReader	customizeReader(ObjectReader reader, JavaType javaType)	Subclasses can use this method to customize ObjectReader used for reading values.
protected ObjectWriter	customizeWriter(ObjectWriter writer, JavaType javaType, MediaType contentType)	Subclasses can use this method to customize ObjectWriter used for writing values.
protected Charset	getCharset(MediaType contentType)	Determine the charset to use for JSON input.
protected Long	getContentLength(Object object, MediaType contentType)	Returns the content length for the given type.
protected MediaType	getDefaultContentType(Object object)	Returns the default content type for the given type.
protected JavaType	getJavaType(Type type, Class<?> contextClass)	Return the Jackson JavaType for the specified type and context class.
protected JsonEncoding	getJsonEncoding(MediaType contentType)	Determine the JSON encoding to use for the given content type.
protected List<MediaType>	getMediaTypesForProblemDetail()	Return the supported media type(s) for ProblemDetail.
ObjectMapper	getObjectMapper()	Return the main ObjectMapper in use.
private Map<Class<?>,Map<MediaType,ObjectMapper>>	getObjectMapperRegistrations()
Map<MediaType,ObjectMapper>	getObjectMappersForType(Class<?> clazz)	Return ObjectMapper registrations for the given class, if any.
List<MediaType>	getSupportedMediaTypes(Class<?> clazz)	Return the list of media types supported by this converter for the given class.
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.
Object	read(Type type, Class<?> contextClass, HttpInputMessage inputMessage)	Read an object of the given type form the given input message, and returns it.
protected Object	readInternal(Class<?> clazz, HttpInputMessage inputMessage)	Abstract template method that reads the actual object.
private Object	readJavaType(JavaType javaType, HttpInputMessage inputMessage)
void	registerObjectMappersForType(Class<?> clazz, Consumer<Map<MediaType,ObjectMapper>> registrar)	Configure the ObjectMapper instances to use for the given Class.
private ObjectMapper	selectObjectMapper(Class<?> targetType, MediaType targetMediaType)	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 main ObjectMapper to use for Object conversion.
void	setPrettyPrint(boolean prettyPrint)	Whether to use the DefaultPrettyPrinter when writing JSON.
protected void	writeInternal(Object object, Type type, HttpOutputMessage outputMessage)	Abstract template method that writes the actual body.
protected void	writePrefix(JsonGenerator generator, Object object)	Write a prefix before the main content.
protected void	writeSuffix(JsonGenerator generator, Object object)	Write a suffix after the main content.

从类继承的方法 cn.taketoday.http.converter.AbstractGenericHttpMessageConverter

canWrite, supports, write, writeInternal

从类继承的方法 cn.taketoday.http.converter.AbstractHttpMessageConverter

addDefaultHeaders, canRead, canWrite, getDefaultCharset, getSupportedMediaTypes, read, setDefaultCharset, setSupportedMediaTypes, write

从类继承的方法 java.lang.Object

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

从接口继承的方法 cn.taketoday.http.converter.HttpMessageConverter

getSupportedMediaTypes, read, write

字段详细资料

ENCODINGS

private static final HashMap<String,JsonEncoding> ENCODINGS

defaultObjectMapper

protected ObjectMapper defaultObjectMapper

objectMapperRegistrations

@Nullable
private Map<Class<?>,Map<MediaType,ObjectMapper>> objectMapperRegistrations

prettyPrint

@Nullable
private Boolean prettyPrint

ssePrettyPrinter

@Nullable
private final PrettyPrinter ssePrettyPrinter

构造器详细资料

AbstractJackson2HttpMessageConverter

protected AbstractJackson2HttpMessageConverter(ObjectMapper objectMapper)

AbstractJackson2HttpMessageConverter

protected AbstractJackson2HttpMessageConverter(ObjectMapper objectMapper,
 MediaType supportedMediaType)

AbstractJackson2HttpMessageConverter

protected AbstractJackson2HttpMessageConverter(ObjectMapper objectMapper,
 MediaType... supportedMediaTypes)

方法详细资料

setObjectMapper

public void setObjectMapper(ObjectMapper objectMapper)

Configure the main ObjectMapper to use for Object conversion. If not set, a default ObjectMapper instance is created.

Setting a custom-configured ObjectMapper is one way to take further control of the JSON serialization process. For example, an extended SerializerFactory can be configured that provides custom serializers for specific types. Another option for refining the serialization process is to use Jackson's provided annotations on the types to be serialized, in which case a custom-configured ObjectMapper is unnecessary.

另请参阅:

• registerObjectMappersForType(Class, Consumer)

getObjectMapper

public ObjectMapper getObjectMapper()

Return the main ObjectMapper in use.

registerObjectMappersForType

public void registerObjectMappersForType(Class<?> clazz,
 Consumer<Map<MediaType,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 supportedMediaTypes 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.

参数:

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

getObjectMappersForType

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

Return ObjectMapper registrations for the given class, if any.

参数:

clazz - the class to look up for registrations for

返回:

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

getSupportedMediaTypes

public List<MediaType> getSupportedMediaTypes(Class<?> clazz)

从接口复制的说明: HttpMessageConverter

Return the list of media types supported by this converter for the given class. The list may differ from HttpMessageConverter.getSupportedMediaTypes() if the converter does not support the given Class or if it supports it only for a subset of media types.

参数:

clazz - the type of class to check

返回:

the list of media types supported for the given class

getObjectMapperRegistrations

private Map<Class<?>,Map<MediaType,ObjectMapper>> getObjectMapperRegistrations()

getMediaTypesForProblemDetail

protected List<MediaType> getMediaTypesForProblemDetail()

Return the supported media type(s) for ProblemDetail. By default, an empty list, unless overridden in subclasses.

setPrettyPrint

public void setPrettyPrint(boolean prettyPrint)

Whether to use the DefaultPrettyPrinter when writing JSON. This is a shortcut for setting up an ObjectMapper as follows:

 ObjectMapper mapper = new ObjectMapper();
 mapper.configure(SerializationFeature.INDENT_OUTPUT, true);
 converter.setObjectMapper(mapper);
 

configurePrettyPrint

private void configurePrettyPrint()

canRead

public boolean canRead(Class<?> clazz,
 @Nullable
 MediaType mediaType)

从类复制的说明: AbstractHttpMessageConverter

This implementation checks if the given class is supported, and if the supported media types include the given media type.

指定者:

canRead 在接口中 HttpMessageConverter<Object>

覆盖:

canRead 在类中 AbstractHttpMessageConverter<Object>

参数:

clazz - the class to test for readability

mediaType - the media type to read (can be null if not specified); typically the value of a Content-Type header.

返回:

true if readable; false otherwise

canRead

public boolean canRead(Type type,
 @Nullable
 Class<?> contextClass,
 @Nullable
 MediaType mediaType)

从接口复制的说明: GenericHttpMessageConverter

Indicates whether the given type can be read by this converter. This method should perform the same checks than HttpMessageConverter.canRead(Class, MediaType) with additional ones related to the generic type.

指定者:

canRead 在接口中 GenericHttpMessageConverter<Object>

覆盖:

canRead 在类中 AbstractGenericHttpMessageConverter<Object>

参数:

type - the (potentially generic) type to test for readability

contextClass - a context class for the target type, for example a class in which the target type appears in a method signature (can be null)

mediaType - the media type to read, can be null if not specified. Typically the value of a Content-Type header.

返回:

true if readable; false otherwise

canWrite

public boolean canWrite(Class<?> clazz,
 @Nullable
 MediaType mediaType)

从类复制的说明: AbstractHttpMessageConverter

This implementation checks if the given class is supported, and if the supported media types include the given media type.

指定者:

canWrite 在接口中 HttpMessageConverter<Object>

覆盖:

canWrite 在类中 AbstractHttpMessageConverter<Object>

参数:

clazz - the class to test for writability

mediaType - the media type to write (can be null if not specified); typically the value of an Accept header.

返回:

true if writable; false otherwise

selectObjectMapper

@Nullable
private ObjectMapper selectObjectMapper(Class<?> targetType,
 @Nullable
 MediaType targetMediaType)

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).

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.

参数:

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

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

read

public Object read(Type type,
 @Nullable
 Class<?> contextClass,
 HttpInputMessage inputMessage)
            throws IOException,
HttpMessageNotReadableException

从接口复制的说明: GenericHttpMessageConverter

Read an object of the given type form the given input message, and returns it.

参数:

type - the (potentially generic) type of object to return. This type must have previously been passed to the canRead method of this interface, which must have returned true.

contextClass - a context class for the target type, for example a class in which the target type appears in a method signature (can be null)

inputMessage - the HTTP input message to read from

返回:

the converted object

抛出:

IOException - in case of I/O errors

HttpMessageNotReadableException - in case of conversion errors

readInternal

protected Object readInternal(Class<?> clazz,
 HttpInputMessage inputMessage)
                       throws IOException,
HttpMessageNotReadableException

从类复制的说明: AbstractHttpMessageConverter

Abstract template method that reads the actual object. Invoked from AbstractHttpMessageConverter.read(java.lang.Class<? extends T>, cn.taketoday.http.HttpInputMessage).

指定者:

readInternal 在类中 AbstractHttpMessageConverter<Object>

参数:

clazz - the type of object to return

inputMessage - the HTTP input message to read from

返回:

the converted object

抛出:

IOException - in case of I/O errors

HttpMessageNotReadableException - in case of conversion errors

readJavaType

private Object readJavaType(JavaType javaType,
 HttpInputMessage inputMessage)
                     throws IOException

抛出:

IOException

customizeReader

protected ObjectReader customizeReader(ObjectReader reader,
 JavaType javaType)

Subclasses can use this method to customize ObjectReader used for reading values.

参数:

reader - the reader instance to customize

javaType - the target type of element values to read to

返回:

the customized ObjectReader

getCharset

protected Charset getCharset(@Nullable
 MediaType contentType)

Determine the charset to use for JSON input.

By default this is either the charset from the input MediaType or otherwise falling back on UTF-8. Can be overridden in subclasses.

参数:

contentType - the content type of the HTTP input message

返回:

the charset to use

writeInternal

protected void writeInternal(Object object,
 @Nullable
 Type type,
 HttpOutputMessage outputMessage)
                      throws IOException,
HttpMessageNotWritableException

从类复制的说明: AbstractGenericHttpMessageConverter

Abstract template method that writes the actual body. Invoked from AbstractGenericHttpMessageConverter.write(T, java.lang.reflect.Type, cn.taketoday.http.MediaType, cn.taketoday.http.HttpOutputMessage).

指定者:

writeInternal 在类中 AbstractGenericHttpMessageConverter<Object>

参数:

object - the object to write to the output message

type - the type of object to write (may be null)

outputMessage - the HTTP output message to write to

抛出:

IOException - in case of I/O errors

HttpMessageNotWritableException - in case of conversion errors

customizeWriter

protected ObjectWriter customizeWriter(ObjectWriter writer,
 @Nullable
 JavaType javaType,
 @Nullable
 MediaType contentType)

Subclasses can use this method to customize ObjectWriter used for writing values.

参数:

writer - the writer instance to customize

javaType - the type of element values to write

contentType - the selected media type

返回:

the customized ObjectWriter

writePrefix

protected void writePrefix(JsonGenerator generator,
 Object object)
                    throws IOException

Write a prefix before the main content.

参数:

generator - the generator to use for writing content.

object - the object to write to the output message.

抛出:

IOException

writeSuffix

protected void writeSuffix(JsonGenerator generator,
 Object object)
                    throws IOException

Write a suffix after the main content.

参数:

generator - the generator to use for writing content.

object - the object to write to the output message.

抛出:

IOException

getJavaType

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

Return the Jackson JavaType for the specified type and context class.

参数:

type - the generic type to return the Jackson JavaType for

contextClass - a context class for the target type, for example a class in which the target type appears in a method signature (can be null)

返回:

the Jackson JavaType

getJsonEncoding

protected JsonEncoding getJsonEncoding(@Nullable
 MediaType contentType)

Determine the JSON encoding to use for the given content type.

参数:

contentType - the media type as requested by the caller

返回:

the JSON encoding to use (never null)

getDefaultContentType

@Nullable
protected MediaType getDefaultContentType(Object object)
                                   throws IOException

从类复制的说明: AbstractHttpMessageConverter

Returns the default content type for the given type. Called when AbstractHttpMessageConverter.write(T, cn.taketoday.http.MediaType, cn.taketoday.http.HttpOutputMessage) is invoked without a specified content type parameter.

By default, this returns the first element of the supportedMediaTypes property, if any. Can be overridden in subclasses.

覆盖:

getDefaultContentType 在类中 AbstractHttpMessageConverter<Object>

参数:

object - the type to return the content type for

返回:

the content type, or null if not known

抛出:

IOException

getContentLength

protected Long getContentLength(Object object,
 @Nullable
 MediaType contentType)
                         throws IOException

从类复制的说明: AbstractHttpMessageConverter

Returns the content length for the given type.

By default, this returns null, meaning that the content length is unknown. Can be overridden in subclasses.

覆盖:

getContentLength 在类中 AbstractHttpMessageConverter<Object>

参数:

object - the type to return the content length for

返回:

the content length, or null if not known

抛出:

IOException