Usually to build a Spring Boot executable JAR file is to set
<executable>true</executable> under the
spring-boot-maven-plugin section in pom.xml. I tried that plus
changing layout and packaging to jar, but still cannot run the
resulting jar or war file by itself. Spewed out infinite loop stack
trace.
A little more digging seems to suggest war overlay does not play
nicely with Spring Boot executable pacakaging in general, see:
https://github.com/spring-projects/spring-boot/issues/1030
So you may have to resort to Ray's suggestion of running the war
file via java -jar, or deploy the war file to a container of your
choice.
David