In einer Service- bzw. Microservice-Architektur stellt sich irgendwann unweigerlich die Frage wie man komplexe Workflows, die über mehrere Services hinweg gehen, orchestrieren möchte. Dabei stehen sich die Event- und die Workflow-Architektur anscheinend als unterschiedliche Paradigmen gegenüber. Wie können wir mit einfachen Architekturmaßnahmen die Arbeitsteilung von Teams/Abteilungen unterstützen?
Um weiterführende Konzepte besser nachvollziehen zu können, wollen wir uns in den Grundlagen Datenbanken mit Spring Boot, Isolation Level (Isolationsgrad) und Locks beschäftigen.
Why Quartz? motivation Spring comes already with an own timer and this is fine if we have very simple requirements and we don’t really care about state or on which pod the timer is actually running. To be more precise the timer/ job is running in each of our spring containers independently. Lets be honest,…
Problem Often we write JPA Entity classes an have to ensure in a larger team that refactoring doesn’t create performance problems or logical errors in the entity model usual problems are: In your test
Problem In some projects we still may need to manually to reconnect to our JMS provider. For what ever reason the framework or the container cannot do the job for us. As so we have to ensure that an once registered JMS listener re-register itself if something bad happens. Note: Check first if your container…
TL;DR Summary Java Type DB Type Description SAVE Long NUMBER Just using a long as milliseconds, between the current time and midnight, January 1, 1970 UTC is the most secure way. SAVE Instant NUMBER Using in Java an Instant and converting it into a NUMBER to save it in the DB will also avoid any…
Overview To enable Activiti in our JEE project the following steps are needed: Add the maven dependencies — include spring-context Add log4j configuration Add the activiti configuration for CDI integration activiti.cfg.xml Add your first activiti workflow Add an activiti compatible data source to your container Deploy and run it Git Project. Eclipse Plugin To install the…
The problem Sometimes we want to register a default Entity Listeners which are called as soon an entity is persisted, without adding the @EntityListeners annotation to our classes, as in most cases we anyway provide interfaces so we can access data on the entity itself. The problem is, that we cannot annotate our entity listener with…
Problem Sometimes it is confusing how fragments work in Android and interesting side effects like: Why have Fragments empty constructors? Why shouldn’t I pass state variables like they are? Why do I need this Fragment transactions? What does addToBackStack mean and do I need it? Why is sometimes the Activity null in my fragment? Overview…
Problem Often we want to connect to create a secure SSL connection to an HTTPs endpoint which is secured by a self-signed Certificate. If we do so just with a simple call we usually face an nice exception like: Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested…