Package io.temporal.common.converter

Interface PayloadConverter

All Known Implementing Classes:

ByteArrayPayloadConverter, GsonJsonPayloadConverter, JacksonJsonPayloadConverter, NullPayloadConverter, ProtobufJsonPayloadConverter, ProtobufPayloadConverter

public interface PayloadConverter

Used by the framework to serialize/deserialize method parameters that need to be sent over the wire.

Method Summary

Modifier and Type	Method	Description
<T> T	fromData(io.temporal.api.common.v1.Payload content, java.lang.Class<T> valueType, java.lang.reflect.Type valueGenericType)	Implements conversion of a single value.
java.lang.String	getEncodingType()	Each PayloadConverter has an Encoding Type that it handles.
java.util.Optional<io.temporal.api.common.v1.Payload>	toData(java.lang.Object value)	Implements conversion of a list of values.
default PayloadConverter	withContext(SerializationContext context)	A correct implementation of this interface should have a fully functional "contextless" implementation.

Method Detail

getEncodingType

java.lang.String getEncodingType()

Each PayloadConverter has an Encoding Type that it handles. Each PayloadConverter should add the information about its Encoding Type into the Payload it produces inside toData(Object) by associating it with the EncodingKeys.METADATA_ENCODING_KEY key attached to the Payload's Metadata using Payload.Builder.putMetadata(String, ByteString).

Returns:

encoding type that this converter handles.

toData

java.util.Optional<io.temporal.api.common.v1.Payload> toData(java.lang.Object value)
                                                      throws DataConverterException

Implements conversion of a list of values.

Parameters:

value - Java value to convert.

Returns:

converted value

Throws:

DataConverterException - if conversion of the value passed as parameter failed for any reason.

See Also:

getEncodingType javadoc for an important implementation detail

fromData

<T> T fromData(io.temporal.api.common.v1.Payload content,
               java.lang.Class<T> valueType,
               java.lang.reflect.Type valueGenericType)
        throws DataConverterException

Implements conversion of a single value.

Parameters:

content - Serialized value to convert to a Java object.

valueType - type of the value stored in the content

valueGenericType - generic type of the value stored in the content

Returns:

converted Java object

Throws:

DataConverterException - if conversion of the data passed as parameter failed for any reason.

withContext

@Nonnull
default PayloadConverter withContext(@Nonnull
                                     SerializationContext context)

A correct implementation of this interface should have a fully functional "contextless" implementation. Temporal SDK will call this method when a knowledge of the context exists, but DataConverter can be used directly by user code and sometimes SDK itself without any context.

Note: this method is expected to be cheap and fast. Temporal SDK doesn't always cache the instances and may be calling this method very often. Users are responsible to make sure that this method doesn't recreate expensive objects like Jackson's ObjectMapper on every call.

Parameters:

context - provides information to the data converter about the abstraction the data belongs to

Returns:

an instance of DataConverter that may use the provided context for serialization

See Also:

SerializationContext