Thoughts on Java: Java Weekly 17/15: Java stats, caching and JPA productivity

The Java world is evolving at a rapid pace and it can be challenging to keep track of it. Fortunately lots of great resources are created every week, explaining new features or looking at existing stuff from a different angle.

I am using the Java Weekly series to collect the most interesting links I found during the last week and present them to you all in one place. I hope you find it useful and that it makes it easier for you to keep up-to-date. If you like to suggest a resource or something I can improve on, please leave me a comment.

Java

Do you know which Java version is currently used the most? The people from Plumbr know, at least for their customer base. They collected some interesting statistics from the 758 JVMs monitored by their software: Java version statistics: 2015 edition.
Hell, there are a lot of legacy JVMs out there!

Due to the EOL of Java 7, the migration to Java 8 is currently a hot topic. And as soon as the migration is done, there is time to do some refactoring and use all these handy new features like streams and lambdas, isn't it?
Fabrizio Giudici wrote a blog post showing the refactoring steps in one of his projects and how the code becomes more readable: A real-world example of refactoring with Java 8 streams.

Java EE

If you read Java Weekly regularly (what you should ;-) ), you probably know Vlad Mihalcea and his excellent Hibernate articles. Not long ago, he started to write about caching in Hibernate:

You should definitely have a look at these articles, if you want to learn more about caching in Hibernate!

Caching is also the topic of the next link. The team from ConSol Labs created a nice introduction to
Java Caches: Ehcache, Hazelcast, Infinispan. After a short introduction to their example application, they talk about local and shared caches and show how to implement them with Ehcache, Hazelcast and Infinispan.

Last weeks Java Weekly 16/15 featured a post about the basics of JPA result set mappings and how they can be used to map the result of native queries to entities. This week we have the second post of this series, which shows how to use more complex mappings to map the result to multiple entities and handle additional columns.

Matti Tahvonen wrote some nice articles on how to be more productive when using JPA. In his first post, he showed how to use Spring Data in an Java EE environment and in the second, he used DeltaSpike Data. Both frameworks provide easy ways to generate the most common DAO methods for an entity and can save you quite some work when writing CRUD use cases.

Recordings

Josh Long gave an interesting talk about building microservices with Spring Boot at the vJUG. As always, the talk was recorded and Oleg Shelajev created a nice write-up and a short interview with Josh: Building “Bootiful” Microservices with Spring Cloud by Josh Long.