How to hide credentials in application.properties

create env.properties

add it to .gitignore env.properties

after that inside it fill the credentials

DB_DATABASE=NameofyourappSavedIntoYourDB
DB_USER=yourUsername
DB_PASSWORD=SuperStrongPassword
API_KEY=superkey

import it in application.properties

this will enable to access it but still not committing the credentials

spring.config.import=file:env.properties

spring.datasource.url=jdbc:h2:file:~/${DB_DATABASE}
spring.datasource.username=${DB_USER}
spring.datasource.password=${DB_PASSWORD}