"How to change a e.g. JDBC URI in the configuration of a Java EE application server running in docker and staged environment?"...is one of the recurring airhacks.com, airhacks.io and airhacks.tv questions.
The answer is: don't change it:
Web Apps, SPA, PWA with vanilla Java Script (ES 6+), CSS 3 and WebStandards only. As simple as possible, but not simpler. See you at: (Progressive) Web apps, Single Page Apps and WebStandards airhacks workshops at MUC airport, Winter Edition
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