2 Verticles: The basic processing units of Vert.x

Put simply, a verticle is the fundamental processing unit in Vert.x. The role of a verticle is to encapsulate a technical functional unit for processing events, such as exposing an HTTP API and responding to requests, providing a repository interface on top of a database, or issuing requests to a third-party system. Much like components in technologies like Enterprise JavaBeans, verticles can be deployed, and they have a life cycle.

Asynchronous programming is key to building reactive applications, since they have to scale, and verticles are fundamental in Vert.x for structuring (asynchronous) event-processing code and business logic.

2.1 Writing a verticle

2.1.1 Preparing the project

2.1.2 The verticle class

2.1.3 Running and first observations

2.2 More on verticles

2.2.1 Blocking and the event loop

2.2.2 Asynchronous notification of life-cycle events

2.2.3 Deploying verticles

2.2.4 Passing configuration data

2.3 When code needs to block

2.3.1 Worker verticles

2.3.2 The executeBlocking operation

2.4 So what is really in a verticle?

2.4.1 Verticles and their environment

2.4.2 More on contexts

2.4.3 Bridging Vert.x and non-Vert.x threading models

Summary