Differences between jar and war in Spring Boot?
Spring Boot can be told to produce a 'fat JAR' which includes all of your module/service's dependencies and can be run with java -jar <your jar>
. See "Create an executable JAR with Maven" here.
Spring Boot can also be told to produce a WAR file, in which case you'll likely choose to deploy it to a web container such as Tomcat or Jetty.
Plenty more details on Spring Boot deployment here.
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:
- Change
packaging
towar
(talking about maven'spom.xml
) - Inherit main
spring-boot
application class fromSpringBootServletInitializer
and overrideSpringApplicationBuilder configure(SpringApplicationBuilder)
method (see javadoc) - Make sure to set the
scope
ofspring-boot-starter-tomcat
asprovided
More info in spring-boot documentation
Depends on your deployment. If you are planning to deploy your application to an existing Java EE Application Server (e.g. Tomcat), then standard approach is to perform a war
build.
When you use fat jar approach, your application will be deployed on embedded application container provided by spring boot. Conduct Deploying Spring Boot Applications for more information.