问如何修改Spring boot2 embedded tomcat的文档根

EN

@Value("${server.tomcat.document-root}")
private String documentRoot;

@Bean
public WebServerFactoryCustomizer<ConfigurableWebServerFactory> webServerFactoryCustomizer() {
    return new WebServerFactoryCustomizer<ConfigurableWebServerFactory>() {
        @Override
        public void customize(ConfigurableWebServerFactory factory) {
            if (factory instanceof TomcatServletWebServerFactory) {
                TomcatServletWebServerFactory tomcat = (TomcatServletWebServerFactory) factory;
                if (!StringUtils.isEmpty(documentRoot)) {
                    File root = new File(documentRoot);
                    tomcat.setDocumentRoot(root);
                }
            }
        }
    };
}

server.servlet.contextPath=/yourpathgoeshere