java.lang.Object

org.springframework.kafka.support.serializer.JsonDeserializer<T>

Type Parameters:: T - class of the entity, representing messages

All Implemented Interfaces:: Closeable, AutoCloseable, org.apache.kafka.common.serialization.Deserializer<T>

public class JsonDeserializer<T> extends Object implements org.apache.kafka.common.serialization.Deserializer<T>

Generic Deserializer for receiving JSON from Kafka and return Java objects.

IMPORTANT: Configuration must be done completely with property setters or via configure(Map, boolean), not a mixture. If any setters have been called, configure(Map, boolean) will be a no-op.

Author:: Igor Stepanov, Artem Bilan, Gary Russell, Yanming Zhou, Elliot Kennedy, Torsten Schleede, Ivan Ponomarev

Field Summary

Fields

Modifier and Type

Field

Description

static final String

KEY_DEFAULT_TYPE

Kafka config property for the default key type if no header.

static final String

KEY_TYPE_METHOD

A method name to determine the JavaType to deserialize the key to: 'com.Foo.deserialize'.

protected final com.fasterxml.jackson.databind.ObjectMapper

objectMapper

static final String

REMOVE_TYPE_INFO_HEADERS

Kafka config property for removing type headers (default true).

protected com.fasterxml.jackson.databind.JavaType

targetType

static final String

TRUSTED_PACKAGES

Kafka config property for trusted deserialization packages.

static final String

TYPE_MAPPINGS

Kafka config property to add type mappings to the type mapper: 'foo=com.Foo,bar=com.Bar'.

protected Jackson2JavaTypeMapper

typeMapper

static final String

USE_TYPE_INFO_HEADERS

Kafka config property for using type headers (default true).

static final String

VALUE_DEFAULT_TYPE

Kafka config property for the default value type if no header.

static final String

VALUE_TYPE_METHOD

A method name to determine the JavaType to deserialize the value to: 'com.Foo.deserialize'.
Constructor Summary

Constructors

Constructor

Description

JsonDeserializer()

Construct an instance with a default ObjectMapper.

JsonDeserializer(com.fasterxml.jackson.core.type.TypeReference<? super T> targetType)

Construct an instance with the provided target type, and a default ObjectMapper.

JsonDeserializer(com.fasterxml.jackson.core.type.TypeReference<? super T> targetType, boolean useHeadersIfPresent)

Construct an instance with the provided target type, and useHeadersIfPresent with a default ObjectMapper.

JsonDeserializer(com.fasterxml.jackson.core.type.TypeReference<? super T> targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper)

Construct an instance with the provided target type, and ObjectMapper.

JsonDeserializer(com.fasterxml.jackson.core.type.TypeReference<? super T> targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper, boolean useHeadersIfPresent)

Construct an instance with the provided target type, ObjectMapper and useHeadersIfPresent.

JsonDeserializer(com.fasterxml.jackson.databind.JavaType targetType)

Construct an instance with the provided target type, and a default ObjectMapper.

JsonDeserializer(com.fasterxml.jackson.databind.JavaType targetType, boolean useHeadersIfPresent)

Construct an instance with the provided target type, and useHeadersIfPresent with a default ObjectMapper.

JsonDeserializer(com.fasterxml.jackson.databind.JavaType targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper)

Construct an instance with the provided target type, and ObjectMapper.

JsonDeserializer(com.fasterxml.jackson.databind.JavaType targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper, boolean useHeadersIfPresent)

Construct an instance with the provided target type, ObjectMapper and useHeadersIfPresent.

JsonDeserializer(com.fasterxml.jackson.databind.ObjectMapper objectMapper)

Construct an instance with the provided ObjectMapper.

JsonDeserializer(Class<? super T> targetType)

Construct an instance with the provided target type, and a default ObjectMapper.

JsonDeserializer(Class<? super T> targetType, boolean useHeadersIfPresent)

Construct an instance with the provided target type, and useHeadersIfPresent with a default ObjectMapper.

JsonDeserializer(Class<? super T> targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper)

Construct an instance with the provided target type, and ObjectMapper.

JsonDeserializer(Class<? super T> targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper, boolean useHeadersIfPresent)

Construct an instance with the provided target type, ObjectMapper and useHeadersIfPresent.
Method Summary

Modifier and Type

Method

Description

void

addTrustedPackages(String... packages)

Add trusted packages for deserialization.

void

close()

void

configure(Map<String,?> configs, boolean isKey)

<X> JsonDeserializer<X>

copyWithType(com.fasterxml.jackson.core.type.TypeReference<? super X> newTargetType)

Copies this deserializer with same configuration, except new target type reference is used.

<X> JsonDeserializer<X>

copyWithType(com.fasterxml.jackson.databind.JavaType newTargetType)

Copies this deserializer with same configuration, except new target java type is used.

<X> JsonDeserializer<X>

copyWithType(Class<? super X> newTargetType)

Copies this deserializer with same configuration, except new target type is used.

T

deserialize(String topic, byte[] data)

T

deserialize(String topic, org.apache.kafka.common.header.Headers headers, byte[] data)

JsonDeserializer<T>

dontRemoveTypeHeaders()

Don't remove type information headers.

JsonDeserializer<T>

forKeys()

Designate this deserializer for deserializing keys (default is values); only applies if the default type mapper is used.

Jackson2JavaTypeMapper

getTypeMapper()

JsonDeserializer<T>

ignoreTypeHeaders()

Ignore type information headers and use the configured target class.

void

setRemoveTypeHeaders(boolean removeTypeHeaders)

Set to false to retain type information headers after deserialization.

void

setTypeFunction(BiFunction<byte[],org.apache.kafka.common.header.Headers,com.fasterxml.jackson.databind.JavaType> typeFunction)

Set a BiFunction that receives the data to be deserialized and the headers and returns a JavaType.

void

setTypeMapper(Jackson2JavaTypeMapper typeMapper)

Set a customized type mapper.

void

setTypeResolver(JsonTypeResolver typeResolver)

Set a JsonTypeResolver that receives the data to be deserialized and the headers and returns a JavaType.

void

setUseTypeHeaders(boolean useTypeHeaders)

Set to false to ignore type information in headers and use the configured target type instead.

void

setUseTypeMapperForKey(boolean isKey)

Configure the default Jackson2JavaTypeMapper to use key type headers.

JsonDeserializer<T>

trustedPackages(String... packages)

Add trusted packages to the default type mapper.

JsonDeserializer<T>

typeFunction(BiFunction<byte[],org.apache.kafka.common.header.Headers,com.fasterxml.jackson.databind.JavaType> typeFunction)

Set a BiFunction that receives the data to be deserialized and the headers and returns a JavaType.

JsonDeserializer<T>

typeMapper(Jackson2JavaTypeMapper mapper)

Use the supplied Jackson2JavaTypeMapper.

JsonDeserializer<T>

typeResolver(JsonTypeResolver resolver)

Set a JsonTypeResolver that receives the data to be deserialized and the headers and returns a JavaType.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.kafka.common.serialization.Deserializer
deserialize

Field Details
- KEY_DEFAULT_TYPE
  
  public static final String KEY_DEFAULT_TYPE
  
  Kafka config property for the default key type if no header.
  See Also:
  
  Constant Field Values
- VALUE_DEFAULT_TYPE
  
  public static final String VALUE_DEFAULT_TYPE
  
  Kafka config property for the default value type if no header.
  See Also:
  
  Constant Field Values
- TRUSTED_PACKAGES
  
  public static final String TRUSTED_PACKAGES
  
  Kafka config property for trusted deserialization packages.
  See Also:
  
  Constant Field Values
- TYPE_MAPPINGS
  
  public static final String TYPE_MAPPINGS
  
  Kafka config property to add type mappings to the type mapper: 'foo=com.Foo,bar=com.Bar'.
  See Also:
  
  Constant Field Values
- REMOVE_TYPE_INFO_HEADERS
  
  public static final String REMOVE_TYPE_INFO_HEADERS
  
  Kafka config property for removing type headers (default true).
  See Also:
  
  Constant Field Values
- USE_TYPE_INFO_HEADERS
  
  public static final String USE_TYPE_INFO_HEADERS
  
  Kafka config property for using type headers (default true).
  Since:
  
  2.2.3
  
  See Also:
  
  Constant Field Values
- KEY_TYPE_METHOD
  
  public static final String KEY_TYPE_METHOD
  
  A method name to determine the JavaType to deserialize the key to: 'com.Foo.deserialize'. See JsonTypeResolver.resolveType(java.lang.String, byte[], org.apache.kafka.common.header.Headers) for the signature.
  See Also:
  
  Constant Field Values
- VALUE_TYPE_METHOD
  
  public static final String VALUE_TYPE_METHOD
  
  A method name to determine the JavaType to deserialize the value to: 'com.Foo.deserialize'. See JsonTypeResolver.resolveType(java.lang.String, byte[], org.apache.kafka.common.header.Headers) for the signature.
  See Also:
  
  Constant Field Values
- objectMapper
  
  protected final com.fasterxml.jackson.databind.ObjectMapper objectMapper
- targetType
  
  protected com.fasterxml.jackson.databind.JavaType targetType
- typeMapper
  
  protected Jackson2JavaTypeMapper typeMapper
Constructor Details
- JsonDeserializer
  
  public JsonDeserializer()
  
  Construct an instance with a default ObjectMapper.
- JsonDeserializer
  
  public JsonDeserializer(com.fasterxml.jackson.databind.ObjectMapper objectMapper)
  
  Construct an instance with the provided ObjectMapper.
  
  Parameters:
  
  objectMapper - a custom object mapper.
- JsonDeserializer
  
  public JsonDeserializer(@Nullable Class<? super T> targetType)
  
  Construct an instance with the provided target type, and a default ObjectMapper.
  
  Parameters:
  
  targetType - the target type to use if no type info headers are present.
- JsonDeserializer
  
  public JsonDeserializer(@Nullable com.fasterxml.jackson.core.type.TypeReference<? super T> targetType)
  
  Construct an instance with the provided target type, and a default ObjectMapper.
  
  Parameters:
  
  targetType - the target type reference to use if no type info headers are present.
  
  Since:
  
  2.3
- JsonDeserializer
  
  public JsonDeserializer(@Nullable com.fasterxml.jackson.databind.JavaType targetType)
  
  Construct an instance with the provided target type, and a default ObjectMapper.
  
  Parameters:
  
  targetType - the target java type to use if no type info headers are present.
  
  Since:
  
  2.3
- JsonDeserializer
  
  public JsonDeserializer(@Nullable Class<? super T> targetType, boolean useHeadersIfPresent)
  
  Construct an instance with the provided target type, and useHeadersIfPresent with a default ObjectMapper.
  
  Parameters:
  
  targetType - the target type.
  
  useHeadersIfPresent - true to use headers if present and fall back to target type if not.
  
  Since:
  
  2.2
- JsonDeserializer
  
  public JsonDeserializer(com.fasterxml.jackson.core.type.TypeReference<? super T> targetType, boolean useHeadersIfPresent)
  
  Construct an instance with the provided target type, and useHeadersIfPresent with a default ObjectMapper.
  
  Parameters:
  
  targetType - the target type reference.
  
  useHeadersIfPresent - true to use headers if present and fall back to target type if not.
  
  Since:
  
  2.3
- JsonDeserializer
  
  public JsonDeserializer(com.fasterxml.jackson.databind.JavaType targetType, boolean useHeadersIfPresent)
  
  Construct an instance with the provided target type, and useHeadersIfPresent with a default ObjectMapper.
  
  Parameters:
  
  targetType - the target java type.
  
  useHeadersIfPresent - true to use headers if present and fall back to target type if not.
  
  Since:
  
  2.3
- JsonDeserializer
  
  public JsonDeserializer(Class<? super T> targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper)
  
  Construct an instance with the provided target type, and ObjectMapper.
  
  Parameters:
  
  targetType - the target type to use if no type info headers are present.
  
  objectMapper - the mapper. type if not.
- JsonDeserializer
  
  public JsonDeserializer(com.fasterxml.jackson.core.type.TypeReference<? super T> targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper)
  
  Construct an instance with the provided target type, and ObjectMapper.
  
  Parameters:
  
  targetType - the target type reference to use if no type info headers are present.
  
  objectMapper - the mapper. type if not.
- JsonDeserializer
  
  public JsonDeserializer(com.fasterxml.jackson.databind.JavaType targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper)
  
  Construct an instance with the provided target type, and ObjectMapper.
  
  Parameters:
  
  targetType - the target java type to use if no type info headers are present.
  
  objectMapper - the mapper. type if not.
- JsonDeserializer
  
  public JsonDeserializer(@Nullable Class<? super T> targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper, boolean useHeadersIfPresent)
  
  Construct an instance with the provided target type, ObjectMapper and useHeadersIfPresent.
  
  Parameters:
  
  targetType - the target type.
  
  objectMapper - the mapper.
  
  useHeadersIfPresent - true to use headers if present and fall back to target type if not.
  
  Since:
  
  2.2
- JsonDeserializer
  
  public JsonDeserializer(com.fasterxml.jackson.core.type.TypeReference<? super T> targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper, boolean useHeadersIfPresent)
  
  Construct an instance with the provided target type, ObjectMapper and useHeadersIfPresent.
  
  Parameters:
  
  targetType - the target type reference.
  
  objectMapper - the mapper.
  
  useHeadersIfPresent - true to use headers if present and fall back to target type if not.
  
  Since:
  
  2.3
- JsonDeserializer
  
  public JsonDeserializer(@Nullable com.fasterxml.jackson.databind.JavaType targetType, com.fasterxml.jackson.databind.ObjectMapper objectMapper, boolean useHeadersIfPresent)
  
  Construct an instance with the provided target type, ObjectMapper and useHeadersIfPresent.
  
  Parameters:
  
  targetType - the target type reference.
  
  objectMapper - the mapper.
  
  useHeadersIfPresent - true to use headers if present and fall back to target type if not.
  
  Since:
  
  2.3
Method Details
- getTypeMapper
  
  public Jackson2JavaTypeMapper getTypeMapper()
- setTypeMapper
  
  public void setTypeMapper(Jackson2JavaTypeMapper typeMapper)
  
  Set a customized type mapper. If the mapper is an AbstractJavaTypeMapper, any class mappings configured in the mapper will be added to the trusted packages.
  
  Parameters:
  
  typeMapper - the type mapper.
  
  Since:
  
  2.1
- setUseTypeMapperForKey
  
  public void setUseTypeMapperForKey(boolean isKey)
  
  Configure the default Jackson2JavaTypeMapper to use key type headers.
  
  Parameters:
  
  isKey - Use key type headers if true
  
  Since:
  
  2.1.3
- setRemoveTypeHeaders
  
  public void setRemoveTypeHeaders(boolean removeTypeHeaders)
  
  Set to false to retain type information headers after deserialization. Default true.
  
  Parameters:
  
  removeTypeHeaders - true to remove headers.
  
  Since:
  
  2.2
- setUseTypeHeaders
  
  public void setUseTypeHeaders(boolean useTypeHeaders)
  
  Set to false to ignore type information in headers and use the configured target type instead. Only applies if the preconfigured type mapper is used. Default true.
  
  Parameters:
  
  useTypeHeaders - false to ignore type headers.
  
  Since:
  
  2.2.8
- setTypeFunction
  
  public void setTypeFunction(BiFunction<byte[],org.apache.kafka.common.header.Headers,com.fasterxml.jackson.databind.JavaType> typeFunction)
  
  Set a BiFunction that receives the data to be deserialized and the headers and returns a JavaType.
  
  Parameters:
  
  typeFunction - the function.
  
  Since:
  
  2.5
- setTypeResolver
  
  public void setTypeResolver(JsonTypeResolver typeResolver)
  
  Set a JsonTypeResolver that receives the data to be deserialized and the headers and returns a JavaType.
  
  Parameters:
  
  typeResolver - the resolver.
  
  Since:
  
  2.5.3
- configure
  
  public void configure(Map<String,?> configs, boolean isKey)
  
  Specified by:
  
  configure in interface org.apache.kafka.common.serialization.Deserializer<T>
- addTrustedPackages
  
  public void addTrustedPackages(String... packages)
  
  Add trusted packages for deserialization.
  
  Parameters:
  
  packages - the packages.
  
  Since:
  
  2.1
- deserialize
  
  public T deserialize(String topic, org.apache.kafka.common.header.Headers headers, byte[] data)
  
  Specified by:
  
  deserialize in interface org.apache.kafka.common.serialization.Deserializer<T>
- deserialize
  
  public T deserialize(String topic, @Nullable byte[] data)
  
  Specified by:
  
  deserialize in interface org.apache.kafka.common.serialization.Deserializer<T>
- close
  
  public void close()
  
  Specified by:
  
  close in interface AutoCloseable
  
  Specified by:
  
  close in interface Closeable
  
  Specified by:
  
  close in interface org.apache.kafka.common.serialization.Deserializer<T>
- copyWithType
  
  public <X> JsonDeserializer<X> copyWithType(Class<? super X> newTargetType)
  
  Copies this deserializer with same configuration, except new target type is used.
  
  Type Parameters:
  
  X - new deserialization result type
  
  Parameters:
  
  newTargetType - type used for when type headers are missing, not null
  
  Returns:
  
  new instance of deserializer with type changes
  
  Since:
  
  2.6
- copyWithType
  
  public <X> JsonDeserializer<X> copyWithType(com.fasterxml.jackson.core.type.TypeReference<? super X> newTargetType)
  
  Copies this deserializer with same configuration, except new target type reference is used.
  
  Type Parameters:
  
  X - new deserialization result type
  
  Parameters:
  
  newTargetType - type reference used for when type headers are missing, not null
  
  Returns:
  
  new instance of deserializer with type changes
  
  Since:
  
  2.6
- copyWithType
  
  public <X> JsonDeserializer<X> copyWithType(com.fasterxml.jackson.databind.JavaType newTargetType)
  
  Copies this deserializer with same configuration, except new target java type is used.
  
  Type Parameters:
  
  X - new deserialization result type
  
  Parameters:
  
  newTargetType - java type used for when type headers are missing, not null
  
  Returns:
  
  new instance of deserializer with type changes
  
  Since:
  
  2.6
- forKeys
  
  public JsonDeserializer<T> forKeys()
  
  Designate this deserializer for deserializing keys (default is values); only applies if the default type mapper is used.
  
  Returns:
  
  the deserializer.
  
  Since:
  
  2.3
- dontRemoveTypeHeaders
  
  public JsonDeserializer<T> dontRemoveTypeHeaders()
  
  Don't remove type information headers.
  Returns:
  
  the deserializer.
  
  Since:
  
  2.3
  
  See Also:
  
  setRemoveTypeHeaders(boolean)
- ignoreTypeHeaders
  
  public JsonDeserializer<T> ignoreTypeHeaders()
  
  Ignore type information headers and use the configured target class.
  Returns:
  
  the deserializer.
  
  Since:
  
  2.3
  
  See Also:
  
  setUseTypeHeaders(boolean)
- typeMapper
  
  public JsonDeserializer<T> typeMapper(Jackson2JavaTypeMapper mapper)
  
  Use the supplied Jackson2JavaTypeMapper.
  Parameters:
  
  mapper - the mapper.
  
  Returns:
  
  the deserializer.
  
  Since:
  
  2.3
  
  See Also:
  
  setTypeMapper(Jackson2JavaTypeMapper)
- trustedPackages
  
  public JsonDeserializer<T> trustedPackages(String... packages)
  
  Add trusted packages to the default type mapper.
  
  Parameters:
  
  packages - the packages.
  
  Returns:
  
  the deserializer.
  
  Since:
  
  2,5
- typeFunction
  
  public JsonDeserializer<T> typeFunction(BiFunction<byte[],org.apache.kafka.common.header.Headers,com.fasterxml.jackson.databind.JavaType> typeFunction)
  
  Set a BiFunction that receives the data to be deserialized and the headers and returns a JavaType.
  
  Parameters:
  
  typeFunction - the function.
  
  Returns:
  
  the deserializer.
  
  Since:
  
  2.5
- typeResolver
  
  public JsonDeserializer<T> typeResolver(JsonTypeResolver resolver)
  
  Set a JsonTypeResolver that receives the data to be deserialized and the headers and returns a JavaType.
  
  Parameters:
  
  resolver - the resolver.
  
  Returns:
  
  the deserializer.
  
  Since:
  
  2.5.3

Class JsonDeserializer<T>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.kafka.common.serialization.Deserializer

Field Details

KEY_DEFAULT_TYPE

VALUE_DEFAULT_TYPE

TRUSTED_PACKAGES

TYPE_MAPPINGS

REMOVE_TYPE_INFO_HEADERS

USE_TYPE_INFO_HEADERS

KEY_TYPE_METHOD

VALUE_TYPE_METHOD

objectMapper

targetType

typeMapper

Constructor Details

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

JsonDeserializer

Method Details

getTypeMapper

setTypeMapper

setUseTypeMapperForKey

setRemoveTypeHeaders

setUseTypeHeaders

setTypeFunction

setTypeResolver

configure

addTrustedPackages

deserialize

deserialize

close

copyWithType

copyWithType

copyWithType

forKeys

dontRemoveTypeHeaders

ignoreTypeHeaders

typeMapper

trustedPackages

typeFunction

typeResolver