我有这个来自 https://github.com/szerhusenBC/jwt-spring-security-demo/ 的示例我正在尝试使用 mongodb 作为后端，但由于 JwtUserFactory.java
return authorities.stream()
.map(authority -> new SimpleGrantedAuthority(authority.getName().name()))
.collect(Collectors.toList());
这是因为 model.security 包中的 Authority 和 User 类使用 RDBMS 连接，但我使用的是 mongodb 和在我的代码中出现错误。我为 Mongodb 定义了 Authority 和 User，如下所示。谁能指导我开始工作
Authority.java
@Document(collection = "authority")
public class Authority {
@Id
private Long id;
private AuthorityName name;
@DBRef(lazy = true)
private List<User> users;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public AuthorityName getName() {
return name;
}
public void setName(AuthorityName name) {
this.name = name;
}
public List<User> getUsers() {
return users;
}
public void setUsers(List<User> users) {
this.users = users;
}
}
User.java
@Document(collection = "user")
public class User {
@Id
private Long _id;
private String username;
private String password;
private String firstname;
private String lastname;
private String email;
private Boolean enabled;
private Date lastPasswordResetDate;
@DBRef(lazy = true)
private List<Authority> authorities;
public Long getId() {
return _id;
}
public void setId(Long id) {
_id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getFirstname() {
return firstname;
}
public void setFirstname(String firstname) {
this.firstname = firstname;
}
public String getLastname() {
return lastname;
}
public void setLastname(String lastname) {
this.lastname = lastname;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Boolean getEnabled() {
return enabled;
}
public void setEnabled(Boolean enabled) {
this.enabled = enabled;
}
public List<Authority> getAuthorities() {
return authorities;
}
public void setAuthorities(List<Authority> authorities) {
this.authorities = authorities;
}
public Date getLastPasswordResetDate() {
return lastPasswordResetDate;
}
public void setLastPasswordResetDate(Date lastPasswordResetDate) {
this.lastPasswordResetDate = lastPasswordResetDate;
}
}
UserRepository.java
public interface UserRepository extends MongoRepository<User, Double> {
User findByUsername(String username);
}
异常(exception)
以下是我得到的异常
org.springframework.security.authentication.InternalAuthenticationServiceException: null
at org.springframework.security.authentication.dao.DaoAuthenticationProvider.retrieveUser(DaoAuthenticationProvider.java:126) ~[spring-security-core-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.authenticate(AbstractUserDetailsAuthenticationProvider.java:144) ~[spring-security-core-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.authentication.ProviderManager.authenticate(ProviderManager.java:174) ~[spring-security-core-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.parkcity.security.controller.AuthenticationRestController.createAuthenticationToken(AuthenticationRestController.java:44) ~[classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_111]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_111]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_111]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_111]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:220) ~[spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134) ~[spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:648) ~[tomcat-embed-core-8.5.6.jar:8.5.6]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127) ~[spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91) ~[spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:115) ~[spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:169) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.parkcity.security.JwtAuthenticationTokenFilter.doFilterInternal(JwtAuthenticationTokenFilter.java:58) [classes/:na]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:121) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:66) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177) [spring-security-web-4.1.4.RELEASE.jar:4.1.4.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:89) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.5.RELEASE.jar:4.3.5.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:108) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:784) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:802) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1410) [tomcat-embed-core-8.5.6.jar:8.5.6]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.6.jar:8.5.6]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_111]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_111]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.6.jar:8.5.6]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_111]
Caused by: java.lang.NullPointerException: null
at org.parkcity.security.JwtUserFactory.mapToGrantedAuthorities(JwtUserFactory.java:31) ~[classes/:na]
at org.parkcity.security.JwtUserFactory.create(JwtUserFactory.java:24) ~[classes/:na]
at org.parkcity.security.service.JwtUserDetailsServiceImpl.loadUserByUsername(JwtUserDetailsServiceImpl.java:25) ~[classes/:na]
at org.springframework.security.authentication.dao.DaoAuthenticationProvider.retrieveUser(DaoAuthenticationProvider.java:114) ~[spring-security-core-4.1.4.RELEASE.jar:4.1.4.RELEASE]
... 93 common frames omitted
2017-01-13 00:04:11.543 DEBUG 30067 --- [nio-8080-exec-1] o.s.s.w.a.ExceptionTranslationFilter : Calling Authentication entry point.
2017-01-13 00:04:11.544 DEBUG 30067 --- [nio-8080-exec-1] o.s.s.w.header.writers.HstsHeaderWriter : Not injecting HSTS header since it did not match the requestMatcher org.springframework.security.web.header.writers.HstsHeaderWriter$SecureRequestMatcher@12337118
2017-01-13 00:04:11.544 DEBUG 30067 --- [nio-8080-exec-1] s.s.w.c.SecurityContextPersistenceFilter : SecurityContextHolder now cleared, as request processing completed
最佳答案
基本上，您的代码存在不止一个问题。首先，您所指的项目是基于 JPA(即关系数据库)创建的，如果您想使用与 Mongo DB(文档存储)相同的代码库，至少您需要重新考虑数据模型(用户和权威)。但首先让我们试着让这个例子工作，最后我只是建议什么也可以改变。
首先，如果您使用 MongoDb 以获得最佳体验，域对象 id 字段应该具有 String 类型，因为您知道 mongodb 将 id 存储为 ObjectId bson无法转换为 Long 的类型。所以首先把 User.java 改成
@Document(collection = "user")
public class User {
@Id
private String _id;
// bla bla bla
}
与权威对象相同
@Document(collection = "authority")
public class Authority {
@Id
private String _id;
// TODO remove this right now !!! :)
@DBRef(lazy = true)
private List<User> users;
// bla bla bla
}
和用户存储库
public interface UserRepository extends MongoRepository<User, String> {
User findByUsername(String username);
}
在这两个更改之后，您还需要重构引用。
您有权威机构对用户的引用吗？ !!!那是什么 ？ :) 那是来自 JPA 的东西，对于 MongoDb，这个引用毫无意义。删除它!
该项目的下一件事是它依赖于数据存储区有一些预定义数据的事实，请参见 import.sql，因此对于 MongoDb，您需要将数据导入 mongodb 才能成为能够运行该项目。我已经将import.sql转换成MongoShell格式，方便大家使用。
将此插入到 authority 集合中:
{
"_id" : ObjectId("587cb19d1db2732183afb0a9"),
"_class" : "org.parkcity.model.security.Authority",
"name" : "ROLE_ADMIN"
}
{
"_id" : ObjectId("587cb19d1db2732183afb0aa"),
"_class" : "org.parkcity.model.security.Authority",
"name" : "ROLE_USER"
}
将此插入到 user 集合中:
{
"_id" : ObjectId("587cb19d1db2732183afb0ab"),
"_class" : "org.parkcity.model.security.User",
"username" : "admin",
"password" : "$2a$08$lDnHPz7eUkSi6ao14Twuau08mzhWrL4kyZGGU5xfiGALO/Vxd5DOi",
"firstname" : "admin",
"lastname" : "admin",
"email" : "admin@admin.com",
"enabled" : true,
"lastPasswordResetDate" : ISODate("2017-01-16T11:42:21.537+0000"),
"authorities" : [
DBRef("authority", ObjectId("587cb19d1db2732183afb0a9")),
DBRef("authority", ObjectId("587cb19d1db2732183afb0aa"))
]
}
{
"_id" : ObjectId("587cb1a11db2732183afb0ac"),
"_class" : "org.parkcity.model.security.User",
"username" : "user",
"password" : "$2a$08$UkVvwpULis18S19S5pZFn.YHPZt3oaqHZnDwqbCW9pft6uFtkXKDC",
"firstname" : "user",
"lastname" : "user",
"email" : "user@user.com",
"enabled" : true,
"lastPasswordResetDate" : ISODate("2017-01-16T11:42:21.620+0000"),
"authorities" : [
DBRef("authority", ObjectId("587cb19d1db2732183afb0aa"))
]
}
如您所见，我已将包从“org.zerhusen”调整为“org.parkcity”。
就是这样，现在您可以启动项目并进行一些测试。如您所见，我没有添加禁用用户(因此您可以自己添加)。
仅出于您对这种特殊情况的考虑，使用 @DBRefs 纯粹是邪恶的 :) 您在 MogoDb 上，因此将权限存储在与用户相同的集合和对象中，这样会很多更快。
还创建了一个功能齐全的分支(基于 MongoDB)，可在此处获得 https://github.com/babltiga/jwt-spring-security-demo
关于java - 如何以 ManyToMany (RDBMS) 的形式加入两个集合 spring-data-mongodb，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/41534708/