xyz.jetdrone.vertx.lambda

Interface Lambda<T>

All Superinterfaces:

io.vertx.core.Handler<io.vertx.core.eventbus.Message<T>>

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface Lambda<T>
extends io.vertx.core.Handler<io.vertx.core.eventbus.Message<T>>

Your Lambda function's handler is the method that Lambda calls when your function is invoked. In the following example, the class MyFunction implements a lambda handler. The handler takes one object as input and returns a JSON document. (msg) -> { System.out.println(msg.body()); msg.reply(new JsonObject().put("hello", "world")); } The message body is an object that contains the payload that's provided by the invoker. If the payload is a JSON document, the event object is a JsonObject. Otherwise, it's a Buffer. The Message object has methods and properties that provide information about the invocation, the headers, and the execution environment. The handler is executed every time your Lambda function is invoked. Static code outside of the handler or the init(Vertx) method is executed once per instance of the function. If your handler uses resources like SDK clients and database connections, you can create them outside of the handler method to reuse them for multiple invocations. Each instance of your lambda can process multiple invocation events, but it only processes one event at a time. The number of instances processing an event at any given time is your function's concurrency. For more information about the Lambda execution context, see AWS Lambda Execution Context.

Method Summary

Modifier and Type	Method and Description
default java.lang.String	alias()
default void	init(io.vertx.core.Vertx vertx) Default initialization.

Methods inherited from interface io.vertx.core.Handler

handle

Method Detail

alias

default java.lang.String alias()

init

default void init(io.vertx.core.Vertx vertx)

Default initialization. It can be used if a function needs to access vertx or the eventbus.

Parameters:

vertx - the current vertx instance.