Mr. Mhetre's Tech Diary

  How I got Groovy Gorilla (Ubuntu 20.10) on Raspberry Pi 400 Raspberry Pi 400 is an awesome Raspberry Pi 4 device which comes packaged in a keyboard. Just hook it up to monitors and you got a working computer. Raspberry Pi 400 comes with a Raspberry Pi OS preinstalled, but it has it's quirks. I bought Pi 400 to replace my 10 year old laptop which couldn't handle the abuse anymore. My primary use of the Pi 400 is to use it as a workstation and to connect to my work computer over Citrix. There are 2 issues with out-of-the-box Raspberry PI OS which forced me to get back to Ubuntu which is my OS of choice for 15+ years. Citrix could not use both monitors. Though I spent decent number of hours to attempt to use different desktop manager, it just didn't work. Getting sound output to a Bluetooth headset was pain in the neck. Still didn't work reliably all the time. Now, coming to the point, installing

How I got my SpringBoot application to execute a service in multiple threads Enabled SpringBoot application run Async tasks Defined a service method which can be invoked asynchronously and returns CompletableFuture object as required by Spring Let Spring manage service component instance Though not required, configured TaskExecutor Spring could use Enable SpringBoot application to run tasks asynchronously To be able to execute tasks using multiple threads asynchronously SpringBoot application must be annotated with @EnableAsync .   I defined this annotation right after   @SpringBootApplication . @SpringBootApplication @EnableAsync public class NosqlApplication implements CommandLineRunner { Logger logger = LoggerFactory. getLogger (NosqlApplication. class ) ; Aync service method returning CompletableFuture object Spring could invoke tasks synchronously and asynchronously. To be able to invoke tasks asynchronously (and let main thread do other things) I annotated the service method

Spring application can be configured using YAML as effectively as using properties file. With YAML file one can, Create environment specific profiles Define properties at application level Define (or override) properties at profile level Spring Framework loads application.yml by default just the way it loads application.properties. If you want to change the name of the yml file you'll have to use context loader to tell what file to look for. Must knows of the yml based configuration Profiles - YML supports multiple profiles in a single file. One can define environment specific configurations as profiles in a single file. Profiles separator - YML configuration file uses 3 dashes ( --- ) to separate a profile. Every property you define after --- is specific to that profile. Profile name - Give profile a name using spring.config.activate.on-profile property. Active profile(s) - Define which profile or profiles are active using spring.profiles.active property. More than one profile c