It's a little late, but I attended Java Day 2018 on Thursday, so I'd like to share my thoughts here.
When I got out of the office building at noon, it was a sunny day. It's already early summer, but it was relatively cool today. At lunch, I decided to go to the sword-cut noodle shop for the first time in a while at the recommendation of a colleague. I ordered Marler sword-cut noodles, but my colleague made mapo tofu. Although I'm from Hunan, China (Hunan food is said to be the hottest food in China), I'm vulnerable to spicy foods and my friends often call me "fake Hunan people". Therefore, when I order spicy foods, I'm always thrilled and I'm worried that I can eat them today. I was sweating today, but I was able to do it normally. On the contrary, my colleague who is usually strong in spicy foods was too spicy and left half of the mapo tofu. Even though they are of the same manner type, I couldn't even tell the "fake Hunan people" why the spiciness was so different. I hope that the upcoming "Java Day 2018" will be as hot as this Manner taste.
When I arrived at the venue, Sheraton Miyako Hotel Tokyo, it was already past 2 o'clock, and the session from 2 o'clock had already started. This is the first time I have participated in Java Day in many years, but it was my first impression that the scale and number of sponsors have shrunk compared to the past. Since Oracle gave up the development of the JDK, it has been talked about for a while as the end of Java. I wonder if Oracle will not devote itself to Java as much as it used to.
Java EE 8 and now Jakarta EE Various things such as JAX-RS, JSON, Servlet4.0, HTTP / 2, JSF2.3, CDI2.0, BeanValidation2.0 were introduced, but it didn't feel very fresh. I was interested in JSON Pointer / JSON Patch / JSON Binding because of product development, but in the other person's Benchmark result of JSON processing The result was that javax-json wasn't even there.
In the first place, there are still quite a few Application Servers that support Java EE 8, and Java EE has also been transferred to the Eclipse Foundation and will be restarted under the new brand name "Jakarta EE", but I'm wondering what the future path will be.
Java in Serverless Land An open source project called ** Fn Project ** was introduced. The homepage of Fn Project states as follows. 「The Fn project is an open-source container-native serverless platform that you can run anywhere -- any cloud or on-premise. It’s easy to use, supports every programming language, and is extensible and performant. 」 I would like to pay attention to the Fn Project in the future for the purpose of providing a FaaS (Function-as-a-Service) system, which is said to be a further evolution of the serverless architecture.
Get ready for a cloud native, service-meshed Java EE He introduced how to integrate Java EE into the mesh of applications managed by Kubernetes and Istio. Nowadays, business systems are becoming more and more cloud-based, and how Java supports the cloud is an important point related to the future development of Java.
Performance tuning with poor tools and cheap drink JPDM (Java Performance Diagrostic Model) was introduced. Demonstrations of techniques for visualizing the behavior of the JVM, identifying application performance bottlenecks, and improving programs were also conducted using VisualVM. It was.
--Make the scope of synchronization by synchronization as small as possible (naturally) --Performance is better with ConcurrentHashMap than making Map threadsafe with Collections.synchronizedMap --It is better to create a composite key class than to concatenate multiple strings (firstName + familyName) as a HashMap key.
Zhou @ Soft Sink