Posts by Neil Stevenson

Neil is a solution architect for Hazelcast®, the world's leading open source in-memory data grid. In more than 25 years of work in IT, Neil has designed, developed and debugged a number of software systems for companies large and small.

Times Table with JCache 1.1

An example showing Hazelcast support for JCache 1.1. As a maintenance release to the JSR 107 Java Caching Specification, JCache 1.1 was released on 16th December 2017. This is now supported by Hazelcast, from release 3.9.3 onwards, released on 16th…

Hazelcast for Go Getters

Know “Go” but don’t know about “Hazelcast” ? Know “Hazelcast” but don’t know about “Go” ? This tutorial gets you going with both together, in a follow-along style, assuming you only know one of the two. Hello World Naturally, this…

Projections, Joins and Partition Awareness

This example shows some of the newer features of querying, a way that joins can be achieved, and shows the pros and cons of partition aware routing. Although mainly an Hazelcast IMDG example, Hazelcast Jet puts in a guest appearance…

Priority Queueing Using the SPI

Hazelcast provides distributed queues, an implementation of java.util.concurrent.BlockingQueue. However, an implementation of java.util.concurrent.PriorityBlockingQueue is not yet provided. In this example, we’ll see how to write this yourself, using Hazelcast’s SPI (Service Provider Interface). (Note: this is just an example, deliberately…

Fraud Detection near-cache example

An example demonstrating how a near-cache configuration option can be added to an existing application to improve performance. Performance increases, no coding is required. But it’s not a universally applicable solution, there are downsides to be aware of. What is…

Tricolor: Multiple classloaders, multiple Hazelcasts, multiple loggers and multiple colours — all in the one JVM

Why? The normal deployment is for a JVM to contain a single Hazelcast instance, a client or a server. This means that the instance can utilise all the resources available to that JVM. In automated tests, it can frequently be…

Step Away From The Database

A step-by-step example of how to introduce Hazelcast into an existing database backed application. The example here takes a Spring JPA example and augments this with Spring Data Hazelcast for added speed and resilience, without discarding what is already there.…

Spring Boot: Hazelcast for Session Replication

In an earlier blog post, Caching Made Bootiful: The Hazelcast Way, Hazelcast’s Viktor Gamov demonstrated the ease of doing caching with Hazelcast in Spring. In this post, we’ll continue the theme to show how trivial session clustering is to implement…