Web Agents
Swim implements a general purpose distributed object model, called Web Agents, that's easy to program, and just works. It's what object-oriented programming was always meant to be. With key innovations in addressability, statefulness, consistency, boundedness, and composability, Web Agents breathe new life into the old idea of distributed objects.
To implement a Web Agent, simply extend the AbstractAgent Java class, and optionally add a @SwimRoute annotation to give your agents an address space.
@SwimRoute("/person/:id")
class PersonalAgent extends AbstractAgent {
}Jump ahead to lanes to see what goes inside a Web Agent. Dive into the tutorials to see Web Agents in action. Or read on to learn what it really means to be a Web Agent.
Universally Addressable
Every Web Agent has a universal, logical address, in the form of a URI. By decoupling Web Agent's logical addresses from the network addresses of their host machines, Swim applications become invariant to the infrastructure on which they're deployed.
Stateful
Web Agents remember their state in-between operations, eliminating the need for constant database round-trips, and greatly simplifying application development by avoiding object-relational mapping.
Atomic
Each Web Agent executes in a single thread at a time. Though as many distinct Web Agents execute in parallel as you have CPU cores. Combined with a built-in software transactional memory model, Web Agents are naturally atomic, without the overhead of locks or transactions.
Consistent
Together, Web Agents, Lanes, and Links implement a continuous consistency model that's largely transparent developers. Web Agents applications just stays consistent. Continuously. In network real-time.
Encapsulated
The only way in or out of a Web Agent is through links to its lanes. This gives Web Agents total control over the exposure of sensitive data. There's no database to compromise.
Persistent
Databases aren't the only way to store data. Web Agents are internally persistent. By taking persistence off the critical path, the single biggest bottleneck to application performances instantly vanishes. While still letting you keep all the data you have space for.
Bounded
Intrinsic and pervasive backpressure handling automatically adapts the behavior of your application based on network, disk, and CPU availability. And because of its continuous consistency model, developers, for the most part, don't have to care.
Decentralized
Web Agents inherit the natural decentralization of the World Wide Web. Any Web Agent can link to any other, given its URI, and appropriate permissions.
Composable
Unlink REST applications, which don't compose well without introducing significantly polling latency, caching overhead, and consistency problems, Web Agents frictionlessly compose, in real-time, at any scale.
As the name implies, Web Agents were designed from first principles to be first class citizens of the World Wide Web. The Web has evolved from a world-wide hypertext library, into the lingua franca of distributed applications. But the technical foundation of the Web, stateless remote procedurce calls over HTTP, is fundamentally incapable of meeting the needs of modern, autonomous, collaborative applications. Web Agents aim to fill that gap.