org.springframework.kafka.support

Class DefaultKafkaHeaderMapper

java.lang.Object

org.springframework.kafka.support.DefaultKafkaHeaderMapper

All Implemented Interfaces:

KafkaHeaderMapper

public class DefaultKafkaHeaderMapper
extends java.lang.Object
implements KafkaHeaderMapper

Default header mapper for Apache Kafka. Headers in KafkaHeaders are never mapped on outbound messages.

Since:

1.3

Author:

Gary Russell

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DefaultKafkaHeaderMapper.NonTrustedHeaderType Represents a header that could not be decoded due to an untrusted type.
protected static class	DefaultKafkaHeaderMapper.SimplePatternBasedHeaderMatcher A pattern-based header matcher that matches if the specified header matches the specified simple pattern.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	JSON_TYPES Header name for java types of other headers.

Constructor Summary

Constructors

Constructor and Description
DefaultKafkaHeaderMapper() Construct an instance with the default object mapper and default header patterns for outbound headers; all inbound headers are mapped.
DefaultKafkaHeaderMapper(com.fasterxml.jackson.databind.ObjectMapper objectMapper) Construct an instance with the provided object mapper and default header patterns for outbound headers; all inbound headers are mapped.
DefaultKafkaHeaderMapper(com.fasterxml.jackson.databind.ObjectMapper objectMapper, java.lang.String... patterns) Construct an instance with the provided object mapper and the provided header patterns for outbound headers; all inbound headers are mapped.
DefaultKafkaHeaderMapper(java.lang.String... patterns) Construct an instance with a default object mapper and the provided header patterns for outbound headers; all inbound headers are mapped.

Method Summary

Modifier and Type	Method and Description
void	addTrustedPackages(java.lang.String... trustedPackages) Add packages to the trusted packages list (default java.util, java.lang) used when constructing objects from JSON.
void	fromHeaders(org.springframework.messaging.MessageHeaders headers, org.apache.kafka.common.header.Headers target) Map from the given MessageHeaders to the specified target message.
protected com.fasterxml.jackson.databind.ObjectMapper	getObjectMapper() Return the object mapper.
protected boolean	matches(java.lang.String header)
void	toHeaders(org.apache.kafka.common.header.Headers source, java.util.Map<java.lang.String,java.lang.Object> headers) Map from the given target message to abstracted MessageHeaders.
protected boolean	trusted(java.lang.String requestedType)

Methods inherited from class java.lang.Object

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

Field Detail

JSON_TYPES

public static final java.lang.String JSON_TYPES

Header name for java types of other headers.

See Also:

Constant Field Values

Constructor Detail

DefaultKafkaHeaderMapper

public DefaultKafkaHeaderMapper()

Construct an instance with the default object mapper and default header patterns for outbound headers; all inbound headers are mapped. The default pattern list is "!id", "!timestamp" and "*". In addition, none of the headers in KafkaHeaders are ever mapped as headers since they represent data in consumer/producer records.

See Also:

DefaultKafkaHeaderMapper(ObjectMapper)

DefaultKafkaHeaderMapper

public DefaultKafkaHeaderMapper(com.fasterxml.jackson.databind.ObjectMapper objectMapper)

Construct an instance with the provided object mapper and default header patterns for outbound headers; all inbound headers are mapped. The patterns are applied in order, stopping on the first match (positive or negative). Patterns are negated by preceding them with "!". The default pattern list is "!id", "!timestamp" and "*". In addition, none of the headers in KafkaHeaders are ever mapped as headers since they represent data in consumer/producer records.

Parameters:

objectMapper - the object mapper.

See Also:

PatternMatchUtils.simpleMatch(String, String)

DefaultKafkaHeaderMapper

public DefaultKafkaHeaderMapper(java.lang.String... patterns)

Construct an instance with a default object mapper and the provided header patterns for outbound headers; all inbound headers are mapped. The patterns are applied in order, stopping on the first match (positive or negative). Patterns are negated by preceding them with "!". The patterns will replace the default patterns; you generally should not map the "id" and "timestamp" headers. Note: none of the headers in KafkaHeaders are ever mapped as headers since they represent data in consumer/producer records.

Parameters:

patterns - the patterns.

See Also:

PatternMatchUtils.simpleMatch(String, String)

DefaultKafkaHeaderMapper

public DefaultKafkaHeaderMapper(com.fasterxml.jackson.databind.ObjectMapper objectMapper,
                                java.lang.String... patterns)

Construct an instance with the provided object mapper and the provided header patterns for outbound headers; all inbound headers are mapped. The patterns are applied in order, stopping on the first match (positive or negative). Patterns are negated by preceding them with "!". The patterns will replace the default patterns; you generally should not map the "id" and "timestamp" headers. Note: none of the headers in KafkaHeaders are ever mapped as headers since they represent data in consumer/producer records.

Parameters:

objectMapper - the object mapper.

patterns - the patterns.

See Also:

PatternMatchUtils.simpleMatch(String, String)

Method Detail

getObjectMapper

protected com.fasterxml.jackson.databind.ObjectMapper getObjectMapper()

Return the object mapper.

Returns:

the mapper.

addTrustedPackages

public void addTrustedPackages(java.lang.String... trustedPackages)

Add packages to the trusted packages list (default java.util, java.lang) used when constructing objects from JSON. If any of the supplied packages is "*", all packages are trusted. If a class for a non-trusted package is encountered, the header is returned to the application with value of type DefaultKafkaHeaderMapper.NonTrustedHeaderType.

Parameters:

trustedPackages - the packages to trust.

fromHeaders

public void fromHeaders(org.springframework.messaging.MessageHeaders headers,
                        org.apache.kafka.common.header.Headers target)

Description copied from interface: KafkaHeaderMapper

Map from the given MessageHeaders to the specified target message.

Specified by:

fromHeaders in interface KafkaHeaderMapper

Parameters:

headers - the abstracted MessageHeaders.

target - the native target message.

matches

protected boolean matches(java.lang.String header)

toHeaders

public void toHeaders(org.apache.kafka.common.header.Headers source,
                      java.util.Map<java.lang.String,java.lang.Object> headers)

Description copied from interface: KafkaHeaderMapper

Map from the given target message to abstracted MessageHeaders.

Specified by:

toHeaders in interface KafkaHeaderMapper

Parameters:

source - the native target message.

headers - the target headers.

trusted

protected boolean trusted(java.lang.String requestedType)