[java] How to set Spring profile from system variable?

I normally configure the applicationContext using Annotation based configuration rather than XML based configuration. Anyway, I believe both of them have the same priority.

*Answering your question, system variable has higher priority *

Getting profile based beans from applicationContext

• Use @Profile on a Bean

@Component
@Profile("dev")
public class DatasourceConfigForDev

Now, the profile is dev

Note : if the Profile is given as @Profile("!dev") then the profile will exclude dev and be for all others.

• Use profiles attribute in XML

<beans profile="dev">
    <bean id="DatasourceConfigForDev" class="org.skoolguy.profiles.DatasourceConfigForDev"/>
</beans>

Set the value for profile:

• Programmatically via WebApplicationInitializer interface

  In web applications, WebApplicationInitializer can be used to configure the ServletContext programmatically

@Configuration
public class MyWebApplicationInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
            servletContext.setInitParameter("spring.profiles.active", "dev");
    }
}

• Programmatically via ConfigurableEnvironment

  You can also set profiles directly on the environment:

    @Autowired
    private ConfigurableEnvironment env;

    // ...

    env.setActiveProfiles("dev");

• Context Parameter in web.xml

  profiles can be activated in the web.xml of the web application as well, using a context parameter:

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/app-config.xml</param-value>
    </context-param>
    <context-param>
        <param-name>spring.profiles.active</param-name>
        <param-value>dev</param-value>
    </context-param>

• JVM System Parameter

  The profile names passed as the parameter will be activated during application start-up:

  -Dspring.profiles.active=dev
  

  In IDEs, you can set the environment variables and values to use when an application runs. The following is the Run Configuration in Eclipse:

• Environment Variable

  to set via command line : export spring_profiles_active=dev

Any bean that does not specify a profile belongs to “default” profile.

The priority order is :

1. Context parameter in web.xml
2. WebApplicationInitializer
3. JVM System parameter
4. Environment variable