从start.spring.io下载的maven项目,功能选择的web,部署到本地后controller断点能击中，但retrun后提示404，同时后台打印一条error日志
Cannot forward to error page for request [/] as the response has already been committed. As a result, the response may have the wrong status code. If your application is running on WebSphere Application Server you may be able to resolve this problem by setting com.ibm.ws.webcontainer.invokeFlushAfterService to false
解决方法
pom.xm引入
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
就好了。
原文：https://www.cnblogs.com/s1956/p/9214742.html