Differences between jar and war in Spring Boot?

Question

I\'m about to build my first website in Java with Spring Framework using Spring Boot and it\'s much easier to build it in jar, but I have a few questions about

Answer 1

Running spring-boot application as fat *.jar

It is possible to build so called fat JAR that is executable *.jar file with embedded application container (Tomcat as default option). There are spring-boot plugins for various build systems. Here is the one for maven: spring-boot-maven-plugin

To execute the kind of fat *.jar you could simple run command:

java -jar *.jar

Or using spring-boot-maven goal:

mvn spring-boot:run

Building spring-boot application as *.war archive

The other option is to ship your application as old-fashioned war file. It could be deployed to any servlet container out there. Here is step by step how-to list:

1. Change packaging to war (talking about maven's pom.xml)
2. Inherit main spring-boot application class from SpringBootServletInitializer and override SpringApplicationBuilder configure(SpringApplicationBuilder) method (see javadoc)
3. Make sure to set the scope of spring-boot-starter-tomcat as provided

More info in spring-boot documentation