Package com.lucimber.dbus.netty

Class WriteOperationListener<T extends io.netty.util.concurrent.Future<?>>

java.lang.Object
com.lucimber.dbus.netty.WriteOperationListener<T>
Type Parameters:
T - the type of future being listened to, must extend Future
All Implemented Interfaces:
io.netty.util.concurrent.GenericFutureListener<T>, EventListener
public final class WriteOperationListener<T extends io.netty.util.concurrent.Future<?>> extends Object implements io.netty.util.concurrent.GenericFutureListener<T>
A GenericFutureListener that provides consistent logging for write operations and optionally chains custom completion logic.

This listener automatically logs the outcome of write operations using the LoggerUtils.TRANSPORT marker with appropriate log levels:

  • DEBUG - Successful operations
  • ERROR - Failed operations with exception details
  • WARN - Cancelled operations

After logging, the listener can optionally execute custom completion logic via the provided Consumer function.

Usage Examples

Basic logging only: 


 ctx.writeAndFlush(message)
    .addListener(new WriteOperationListener<>(LOGGER));

With custom completion logic: 


 ctx.writeAndFlush(message)
    .addListener(new WriteOperationListener<>(LOGGER, future -> {
        if (future.isSuccess()) {
            // Handle successful write
            processSuccessfulWrite();
        } else {
            // Handle failed write
            handleWriteFailure(future.cause());
        }
    }));

SASL authentication example: 


 ctx.writeAndFlush(authMessage)
    .addListener(new WriteOperationListener<>(LOGGER, future -> {
        if (future.isSuccess()) {
            currentState = State.AWAITING_RESPONSE;
            startResponseTimeout(ctx);
        } else {
            failAuthentication(ctx, "Failed to send auth message");
        }
    }));

This class is thread-safe and can be used across multiple channels and handlers. The logger instance is not required to be static final, making it suitable for use in various contexts where different loggers may be needed.

Since:
1.0
See Also:

  • Constructor Details

    • WriteOperationListener

      public WriteOperationListener(org.slf4j.Logger logger)
      Creates a new WriteOperationListener that only performs logging.

      This constructor creates a listener that will log the outcome of write operations but will not execute any custom completion logic.

      Parameters:
      logger - the logger to use for logging write operation outcomes; must not be null
      Throws:
      NullPointerException - if logger is null

    • WriteOperationListener

      public WriteOperationListener(org.slf4j.Logger logger, Consumer<T> futureConsumer)
      Creates a new WriteOperationListener with custom completion logic.

      This constructor creates a listener that will log the outcome of write operations and then execute the provided custom completion logic.

      Parameters:
      logger - the logger to use for logging write operation outcomes; must not be null
      futureConsumer - optional consumer to execute custom completion logic; may be null
      Throws:
      NullPointerException - if logger is null

  • Method Details

    • operationComplete

      public void operationComplete(T future)
      Called when the write operation completes, regardless of success or failure.

      This method first logs the outcome of the write operation using the LoggerUtils.TRANSPORT marker:

      • If the operation was successful, logs at DEBUG level
      • If the operation failed with an exception, logs at ERROR level with the exception
      • If the operation was cancelled, logs at WARN level

      After logging, if a custom completion consumer was provided during construction, it will be executed with the future as its argument.

      This method is thread-safe and can be called from any thread.

      Specified by:
      operationComplete in interface io.netty.util.concurrent.GenericFutureListener<T extends io.netty.util.concurrent.Future<?>>
      Parameters:
      future - the completed future representing the write operation result