SpringBoot配置SSLUnable to start ServletWebServerApplicationContext due to multiple ServletWebServerFa

SpringBoot配置SSL后出现如下错误：

Unable to start ServletWebServerApplicationContext due to multiple ServletWebServerFactory beans : webServerFactory,servletContainer

完整报错：

org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to multiple ServletWebServerFactory beans : webServerFactory,servletContainer
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:162) ~[spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:582) ~[spring-context-5.3.3.jar:5.3.3]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:144) ~[spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:767) [spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) [spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:426) [spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:326) [spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1311) [spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1300) [spring-boot-2.4.2.jar:2.4.2]
	at ..main(.java:21) [classes/:na]
Caused by: org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to multiple ServletWebServerFactory beans : webServerFactory,servletContainer
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.getWebServerFactory(ServletWebServerApplicationContext.java:214) ~[spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:179) ~[spring-boot-2.4.2.jar:2.4.2]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:159) ~[spring-boot-2.4.2.jar:2.4.2]
	... 9 common frames omitted

也就是由于多个ServletWebServerFactory bean，无法启动ServletWebServerApplicationContext，具体纠错过程不说了，解决步骤：

查看代码里是不是有多个TomcatConfig
查看入口函数是不是加了 TomcatServletWebServerFactory，去掉一个。解决。

@OneToMany、@ManyToOne以及@ManyToMany讲解

一、一对多（@OneToMany）1、单向一对多模型假设通过一个客户实体可以获得多个地址信息。对于一对多的实体关系而言，表结构有两种设计策略，分别是外键关联和表关联。(1) 映射策略---外键关联在数据库中表customer和表结构address定义，如下：

1	create table customer ( id int(20) not null auto_increment, name varchar(100), primary key(id))create table address ( id int(20) not null auto_increment, province varchar(50), city varchar(50), postcode varchar(50), detail varchar(50), customer_id int(20), primary key (id))

注意此时外键定义在多的一方，也就是address表中。