code: public SpringApplication build(String... args) {
  		configureAsChildIfNecessary(args);
  		this.application.addPrimarySources(this.sources);
  		return this.application;
  	}
docs: Returns a fully configured {@link SpringApplication} that is ready to run. Any
  parent that has been configured will be run with the given {@code args}.
  @param args the parent's args
  @return the fully configured {@link SpringApplication}.