Class Stream<T>

java.lang.Object

io.superdurable.dex.PersistenceDefinition

io.superdurable.dex.Stream<T>

Type Parameters:

T - the message type

public final class Stream<T>
extends PersistenceDefinition

Defines a typed best-effort resumable message Stream owned by one Flow type.

Register the exact definition in one PersistenceSchema. All instances of that Flow type share the approximate byte budget. Step writes are immediate and do not roll back when the handler later fails.

Method Summary

Modifier and Type	Method	Description
static <T> Stream<T>	define(String name, Class<T> valueType, long streamCapacityBytes)	Creates a typed Stream definition.
long	getStreamCapacityBytes()	Returns the approximate shared byte budget.
String	getStreamName()	Returns the logical Stream name.
void	write(Context context, T value)	Appends one message immediately from the current Step execution.

Methods inherited from class Object

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

Method Details

define

public static <T> Stream<T> define(String name,
 Class<T> valueType,
 long streamCapacityBytes)

Creates a typed Stream definition.

Type Parameters:

T - the message type

Parameters:

name - the nonblank logical name unique within its Flow

valueType - the concrete message class used for decoding

streamCapacityBytes - the positive approximate shared byte budget

Returns:

an immutable Stream definition

write

public void write(Context context,
 T value)

Appends one message immediately from the current Step execution.

This method sends a fire-and-forget frame to Dex. It may be called repeatedly for the same Stream. Each frame also acts as an implicit activity heartbeat. Storage failures do not fail the Step, but local validation, serialization, or transport failures may throw.

Parameters:

context - the current Step Context; RPC and Flow timeout Contexts are rejected

value - the typed message to append

Throws:

IllegalStateException - if the Context belongs to an RPC or Flow timeout handler

io.grpc.StatusRuntimeException - if the Step invocation is canceled or transport fails

ValueMappingException - if the value cannot be encoded

getStreamName

public String getStreamName()

Returns the logical Stream name.

Returns:

the stable protocol name

getStreamCapacityBytes

public long getStreamCapacityBytes()

Returns the approximate shared byte budget.

Returns:

the positive budget in bytes