[spring boot] war를 만들때 rootAbsolutePath가 null일 경우

@Component
public class CommonMessageContainer {
	@Inject
	RootAbsolutePath rootAbsolutePath;

	@Autowired
	WebApplicationContext webApplicationContext;
    
	public void init() throws Exception {
    	// 그냥 run 할 때에는 rootAbsolutePath가 있으나,
        // war 파일을 만들때는 webApplicationContext에서 값을 넣어줘야 함.
		rootAbsolutePath.setRootAbsolutePath(webApplicationContext.getServletContext().getRealPath("/"));
        
        System.out.println(rootAbsolutePath.toString());
	}
}