Module io.fluxzero.sdk
Package io.fluxzero.sdk.tracking.handling

Class MutableHandler<M>

java.lang.Object
io.fluxzero.sdk.tracking.handling.MutableHandler<M>
Type Parameters:
M - the message type this handler supports
All Implemented Interfaces:
io.fluxzero.common.handling.Handler<M>
public class MutableHandler<M> extends Object implements io.fluxzero.common.handling.Handler<M>
A specialized Handler that maintains and mutates an internal delegate instance.

This handler is designed for use cases where the state of the handler may evolve dynamically across message invocations. It is particularly suited for temporarily scoped objects (e.g. sagas, user sessions).

Behavior

When a handler method returns an instance of the handler’s target class, this instance is stored as the new delegate: 

 Object result = method.invoke(target);
 if (result instanceof MyHandler) {
     target = result; // promote new version
 }

If the method returns null and the method's return type matches the target class, the internal target is cleared, and any registered delete callbacks are triggered.

Lifecycle Hooks

A delete callback can be registered using onDelete(Runnable) to perform cleanup when the handler deletes its state (i.e., returns null).

  • Constructor Details

    • MutableHandler

      public MutableHandler()

  • Method Details

    • getInvoker

      public Optional<io.fluxzero.common.handling.HandlerInvoker> getInvoker(M message)
      Specified by:
      getInvoker in interface io.fluxzero.common.handling.Handler<M>

    • instantiateTarget

      public MutableHandler<M> instantiateTarget()

    • isEmpty

      public boolean isEmpty()

    • onDelete

      public io.fluxzero.common.Registration onDelete(Runnable callback)