Tag Archives: javaee7

Accessing HTTP Session in WebSocket endpoint

It’s possible to obtain a reference to the HttpSession within a WebSocket application using a custom implementation of ServerEndpointConfig.Configurator Here is an example application on Github Steps… Override the modifyHandshakeRequest method call the getHttpSession method on the HandshakeRequest object which is passed into the … Continue reading

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Handling ‘state’ in Java WebSocket applications

By and large, there are two kinds of states in a WebSocket application User/client specific: related to a connected user/Session e.g. user ID, list of subscriptions, last message received etc. Global: state which is relevant across your application and something … Continue reading

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Using CDI with Java EE Concurrency Utilities

This blog post explores usage of CDI along with Java EE Concurrency Utilities – specifically using CDI beans as managed tasks. Here is the sample application on Github Lets begin with a quick overview Java EE Concurrency Utilities provides APIs … Continue reading

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Trending Meetup groups with Redis and Java EE

This is an application which displays the currently trending Meetup groups based on their (live) RSVPs feed. It’s built using Java EE 7 (uses WebSocket client & server APIs, Singleton EJB timers and CDI events to wire things up) and … Continue reading

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Quick tip: managing Stateful EJBs in WebSocket endpoints

@Stateful EJBs can be injected in WebSocket endpoints (supported by the WebSocket specification). There is an one-to-one association between the WebSocket client & endpoint (which is by default) as well as the injected Stateful EJB instance, which makes it an good candidate for storing … Continue reading

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WebSocket endpoint as Singleton EJB

By default … … a WebSocket implementation creates a new (server) endpoint instance per client. In case you need a single instance, you can implement this using a custom ServerEndpointConfig.Configurator (by overriding the getEndpointInstance method) The catch: you might have to sacrifice some … Continue reading

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Using Asynchronous timeouts in the Java WebSocket API

Sending messages in an asynchronous manner avoid blocking the sending thread. This is a great where your solution needs to scale in order to support a large number of clients. But there is a limit on how long can we … Continue reading

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Dynamic provider registration in JAX-RS

The DynamicFeature class in JAX-RS (2.0) allows you to register providers Dynamically i.e. without any pre-defined binding strategy (e.g. annotations) Based on criteria i.e. to help decide which provider to bind to which JAX-RS resource(s) The JAX-RS implementation detects and executes … Continue reading

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WebSocket and CDI integration.. again..

In one of my older blog posts, I had written about what does not work as far as WebSocket and CDI integration within the Java EE Platform 😉 This one talks about what’s possible with CDI in terms of Dependency Injection Interceptors … Continue reading

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Configuring WebSocket server endpoints

WebSocket Server endpoint configuration Before we dive into the details, here is a quick snapshot of the related interfaces Class/Interface Description ServerEndpointConfig A derivative of EndpointConfig interface which is specific for configuration related to server side WebSocket endpoints ServerEndpointConfig.Configurator An … Continue reading

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