

postgresql-*.jar library should be loaded by tomcat: place it to its tomcat's classpath: .../tomcat/lib/

Note access rights and ownership: tomcat:tomcat

-rw-r-----. 1 tomcat tomcat 825943 Mar 23 08:03 /opt/tomcat/latest/lib/postgresql-42.2.5.jar

also schema in URL access should be: jdbc:postgresql (not only postgresql://)

jdbc:postgresql://127.0.0.1:5432/vialactea


Manual: https://jdbc.postgresql.org/documentation/use/


