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Fundamental rules of nature, such as the speed of light and general information theory, set significant limits on the maximum performance we can obtain from traditional system architectures. Learn how you, as a Java developer, can improve performance by orders of magnitude using in-JVM-technology and Java Streams. If, for example, the application server and the database server are located 100 ...

An interesting question was posed in a comment on the DZone-syndicated version of my recent blog post “Arrays.hashCode() Vs. Objects.hash()“. The comment’s author set up examples similar to those used in my blog post and showed different results than I saw. I appreciate the comment author taking the time to post this as it brings up a subtle nuance in ...

Cross-Origin Resource Sharing No ‘Access-Control-Allow-Origin’ header is present on the requested resource. Origin http://www.sesamestreet.com  is therefore not allowed access. If you work with a frontend sometimes, the chances are that you’ve seen the error above before. When it had happened to you for the first time, like any proper developer does, you googled that. As a result, you have probably ...

Learn how leverage Spock 1.2 to slice a Spring context of a legacy application writing integration tests. Have you ever wanted, having some legacy application which you were starting to work on, to write some tests to get know what is going on and possibly be notified about regressions? That feeling when you want to instantiate a single class and ...

This post shows how you can convert a java.sql.ResultSet to JSON and stream it back to the caller. This is useful if you want to send a large dataset from a JDBC DataSource to a web application in JSON format. Streaming allows you to transfer the data, little by little, without having to load it all into the server’s memory. ...

A guide to building the perfect stack for enterprise DevOps teams Every team approaches software tooling differently, but overall we see similar frameworks across most enterprise DevOps teams. Tooling follows the the product from creation to delivery to success (ideally) and back to creation of new releases and products. Most tools fall solidly into one of these 3 categories: product ...

Continuously build, test and monitor your Microservices for optimal performance. Summary For companies migrating their architecture to microservices, anti-patterns can be a major obstacle to success. Here’s how to identify and avoid them. In my last article, Microservice Patterns That Help Large Enterprises Speed Development, Deployment and Extension, we went over some deployment and communication patterns that help keep microservices ...

Get Your Coding Stripes by Building Real Web Projects with 60+ Hrs of Training From the Pros Hey fellow geeks, This week, on our JCG Deals store, we have another extreme offer. We are offering a massive 92% off on The 2019 Interactive Coding Bootcamp. Get it now with only $39, instead of the original price of $499. The 2019 ...

We use ActiveMQ as our messaging layer – sending large volumes of messages with a need for low-latency. Generally it works fine, however in some situations we’ve seen performance problems. After spending too much time testing our infrastructure I think I’ve learned something interesting about ActiveMQ: it can be really quite slow. Although in general messages travel over ActiveMQ without ...