如何使用额外列保存具有多对多映射的对象？

Question

如何使用额外列保存具有多对多映射的对象？ 专栏是“批准”。 使用多对多注释我只调用了setUsersDocuments（用户），它工作正常......如何才能使用额外的列？

文献

@JsonIgnore
    @OneToMany(mappedBy = "document")
    private List<UsersDocuments> documentsForUsers;

用户类

@OneToMany(mappedBy = "user", orphanRemoval = true, cascade= CascadeType.ALL)
private List<UsersDocuments> usersDocuments;

PK

@Embeddable
public class UserDocumentsId implements Serializable {

    @Column(name="user_id")
    private long user;

    @Column(name="document_id")
    private long document;

很多桌子

    @Entity
@Table(name="users_documents")
public class UsersDocuments {

    @EmbeddedId
    private UserDocumentsId id;

    @ManyToOne(fetch = FetchType.LAZY)
    @MapsId("user")
    @JoinColumn(name = "user_id")
    private User user;

    @ManyToOne(fetch = FetchType.LAZY)
    @MapsId("document")
    @JoinColumn(name = "document_id")
    private Document document;

    @Column(name="approval")
    private boolean approval;

保存文件

Document document = new Document(title, desc);
        document.setUploadDatetime(new Date());
        document.setUser(user.get());

        List<User> users = userService.getUsersByRoles(roles);

//        document.setDocumentsForUsers(users); THIS WAS WHEN USING ONLY MANY TO MANY ANNOTATION

        documentService.saveDocument(document);

编辑：Unsuccesfull保存对象 - document.getDocumentsForUsers（）。add（userDocuments）NULL。

Optional<User> user = userService.getUserByEmail(createdBy);
        Document document = new Document(title, desc);
        document.setUploadDatetime(new Date());
        document.setUser(user.get());

        List<User> users = userService.getUsersByRoles(roles);

        for(User userx : users){
            UsersDocuments userDocuments = new UsersDocuments();
            UserDocumentsId id = new UserDocumentsId();

            // Construct the Id with user and document
            id.setUser(userx.getId());
            id.setDocument(document.getId());

            userDocuments.setId(id);
            userDocuments.setApproval(true);

            // This is very important for saving and cascading to work.
            document.getDocumentsForUsers().add(userDocuments);
        }

        documentService.saveDocument(document);

编辑：错误

显示java.lang.NullPointerException：空在com.patrikmaryska.bc_prace.bc_prace.controller.DocumentController.getDocumentFromClient（DocumentController.java:85）〜[类/：NA]在com.patrikmaryska.bc_prace.bc_prace.controller.DocumentController $$ FastClassBySpringCGLIB $ 3a9de86b.invoke（）〜[classes /：na] at org.springframework.cglib.proxy.MethodProxy.invoke（MethodProxy.java:218)~ [spring-core-5.1.8.RELEASE.jar：5.1.8 .RELEASE]在com.patrikmaryska.bc_prace的org.springframework.aop.framework.CglibAopProxy $ DynamicAdvisedInterceptor.intercept（CglibAopProxy.java:684）〜[spring-aop-5.1.8.RELEASE.jar：5.1.8.RELEASE] .bc_prace.controller.DocumentController $$ EnhancerBySpringCGLIB $$ b46e5706.getDocumentFromClient（）〜[classes /：na] at java.base / jdk.internal.reflect.NativeMethodAccessorImpl.invoke0（Native Method）〜[na：na] at java。 java.base / jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke中的base / jdk.internal.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:62）〜[na：na]（DelegatingM ethodAccessorImpl.java:43）〜[na：na] at java.base / java.lang.reflect.Method.invoke（Method.java:567）〜[na：na] at org.springframework.web.method.support。 InvocableHandlerMethod.doInvoke（InvocableHandlerMethod.java:190）〜[弹簧网络5.1.8.RELEASE.jar：5.1.8.RELEASE]在org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest（InvocableHandlerMethod.java:138 ）〜[spring-web-5.1.8.RELEASE.jar：5.1.8.RELEASE]在org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle（ServletInvocableHandlerMethod.java:104）〜[spring- webmvc-5.1.8.RELEASE.jar：5.1.8.RELEASE] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod（RequestMappingHandlerAdapter.java:892)~ [spring-webmvc-5.1.8 .RELEASE.jar：5.1.8.RELEASE]在org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal（RequestMappingHandlerAdapter.java:797）〜[spring-webmvc-5.1.8.RELEASE.jar： 5.1.8.RELEASE]在o org.springframework.web.servlet上的rg.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle（AbstractHandlerMethodAdapter.java:87）〜[spring-webmvc-5.1.8.RELEASE.jar：5.1.8.RELEASE] .dispatcherServlet.doDispatch（DispatcherServlet.java:1039）〜[spring-webmvc-5.1.8.RELEASE.jar：5.1.8.RELEASE] org.springframework.web.servlet.DispatcherServlet.doService（DispatcherServlet.java:942） 〜[spring-webmvc-5.1.8.RELEASE.jar：5.1.8.RELEASE] org.springframework.web.servlet.FrameworkServlet.processRequest（FrameworkServlet.java：1005）〜[spring-webmvc-5.1.8.RELEASE .jar：5.1.8.RELEASE]在javax的org.springframework.web.servlet.FrameworkServlet.doPost（FrameworkServlet.java:908）〜[spring-webmvc-5.1.8.RELEASE.jar：5.1.8.RELEASE] org.springframework.web.servlet.FrameworkServlet.service上的.servlet.http.HttpServlet.service（HttpServlet.java:660）〜[tomcat-embed-core-9.0.21.jar：9.0.21]（FrameworkServlet.java： 882）〜[spring-webmvc-5.1.8.RELEASE.jar：5.1.8.RELEASE]在javax.servlet.http.HttpServlet.s ervice（HttpServlet.java:741）〜[tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:231）〜[tomcat-embed -core-9.0.21.jar：9.0.21] at org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166)~ [tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:53）〜[tomcat-embed-websocket-9.0.21.jar：9.0.21] at org.apache.catalina.core.ApplicationFilterChain。 internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-9.0.21.jar：9.0.21]在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）〜[tomcat-embed -core-9.0.21.jar：9.0.21] at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal（HttpTraceFilter.java:88）〜[spring-boot-actuator-2.1.6。 RELEASE.jar：2.1.6.RELEASE]在org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:109）〜[sprin gg-web-5.1.8.RELEASE.jar：5.1.8.RELEASE]在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-9.0.21.jar ：9.0.21] org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）〜[tomcat-embed-core-9.0.21.jar：9.0.21] org.springframework.security.web在org.springframework.security.web.access.intercept.FilterSecurityInterceptor中的.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:320）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE]。在org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter（FilterSecurityInterceptor.java）中调用（FilterSecurityInterceptor.java:127）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] ：91）〜org.springframework.security.web.FilterChainProxy $ [VirtualFilterChain.doFilter]（[...]在org.s的security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] org.springframework.security.web.FilterChainProxy中的pringframework.security.web.access.ExceptionTranslationFilter.doFilter（ExceptionTranslationFilter.java:119）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] org.springframework.security.web.session.SessionManagementFilter.doFilter（SessionManagementFilter。 java：137）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring -security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter（SecurityContextHolderAwareRequestFilter.java:170)~ [spring-security-web-5.1。 5.RELEASE.jar：5.1.5.RELEASE]在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.1.5.RELEASE。 jar：5.1.5.RELEASE] at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter（RequestCacheAwareFilter.java:63）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE在org.springframework.security的org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] .oauth2.provider.authentication.OAuth2AuthenticationProcessingFilter.doFilter（OAuth2AuthenticationProcessingFilter.java:176）〜[弹簧安全oauth2-2.3.4.RELEASE.jar：NA]在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（在org.springframework.security.web.authentication.logout.LogoutFilter.doFilter（LogoutFilter.java:116）的FilterChainProxy.java:334)~ [spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] ）org.springframework.security.web.FilterChainProxy $ [VirtualFilterChain.doFilter]（[...] - [spring-securit] y-web-5.1.5.RELEASE.jar：5.1.5.RELEASE]在org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal（HeaderWriterFilter.java:74）〜[spring-security-web-5.1.5 .RELEASE.jar：5.1.5.RELEASE]在org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:109）〜[spring-web-5.1.8.RELEASE.jar：5.1.8.RELEASE]在Org.springframework.security的org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE]。 web.context.SecurityContextPersistenceFilter.doFilter（SecurityContextPersistenceFilter.java:105）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter （FilterChainProxy.java:334）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE]位于org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal（WebAsyncManagerIntegrationFilter。 java的：56 ）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE]在org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:109）〜[spring-web-5.1。 8.RELEASE.jar：5.1.8.RELEASE]在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:334）〜[spring-security-web-5.1.5.RELEASE.jar：5.1 .5.RELEASE] org.springframework上的org.springframework.security.web.FilterChainProxy.doFilterInternal（FilterChainProxy.java:215）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate上的.security.web.FilterChainProxy.doFilter（FilterChainProxy.java:178）〜[spring-security-web-5.1.5.RELEASE.jar：5.1.5.RELEASE] DelegatingFilterProxy.java:357）〜[spring-web-5.1.8.RELEASE.jar：5.1.8.RELEASE] org.springframework.web.filter.DelegatingFilterProxy.doFilter（DelegatingFilterProxy.java:270)~ [spring-web -5.1.8.RELEASE.jar：5.1.8.RELEASE]在org.apache.catalina.core.ApplicationFilterChain。 internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-9.0.21.jar：9.0.21]在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）〜[tomcat-embed -core-9.0.21.jar：9.0.21] at org.springframework.web.filter.FormContentFilter.doFilterInternal（FormContentFilter.java:92）〜[spring-web-5.1.8.RELEASE.jar：5.1.8。发布在org.apache.catalina.core上的org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:109）〜[spring-web-5.1.8.RELEASE.jar：5.1.8.RELEASE]。 ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166)~ [tomcat -embed-core-9.0.21.jar：9.0.21] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal（HiddenHttpMethodFilter.java：93）〜[spring-web-5.1.8.RELEASE.jar：5.1。 8.RELEASE]在org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerR） equestFilter.java:109）〜[spring-web-5.1.8.RELEASE.jar：5.1.8.RELEASE]在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed -core-9.0.21.jar：9.0.21] at org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166)~ [tomcat-embed-core-9.0.21.jar：9.0.21]在组织的org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:114）〜[spring-boot-actuator-2.1.6.RELEASE.jar：2.1.6.RELEASE]。 org.springframework.web上的springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal（WebMvcMetricsFilter.java:104）〜[spring-boot-actuator-2.1.6.RELEASE.jar：2.1.6.RELEASE] .filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:109）〜[spring-web-5.1.8.RELEASE.jar：5.1.8.RELEASE] org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java： 193）〜[tomcat-embed-core-9.0.21.jar：9.0.21]在org.apache。 catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166)~ [tomcat-embed-core-9.0.21.jar：9.0.21] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal（CharacterEncodingFilter.java:200 ）〜[spring-web-5.1.8.RELEASE.jar：5.1.8.RELEASE] org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:109）〜[spring-web-5.1.8。在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）〜[tomcat-embed-core-9.0.21.jar：9.0.21]的RELEASE.jar：5.1.8.RELEASE]。 apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166)~ [tomcat-embed-core-9.0.21.jar：9.0.21] at com.patrikmaryska.bc_prace.bc_prace.config.CorsConfig.doFilter（CorsConfig） .java：34）〜[classes /：na] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193)~ [tomcat-embed-core-9.0.21.jar：9.0.21] at at org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFi lterChain.java:166)~ [tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:202）〜[tomcat-embed-core -9.0.21.jar:9.0.21] org.apache.catalina.core.StandardContextValve.invoke（StandardContextValve.java:96）〜[tomcat-embed-core-9.0.21.jar：9.0.21] at org .apache.catalina.authenticator.AuthenticatorBase.invoke（AuthenticatorBase.java:490）〜[tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.catalina.core.StandardHostValve.invoke（StandardHostValve。 java：139）〜[tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java:92）〜[tomcat-embed-core-9.0 。orj.:7.0.21]在org.apache的org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve.java:74）〜[tomcat-embed-core-9.0.21.jar：9.0.21] .catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:343）〜[tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.coyote.http11.Http11Processor.service（Http11Processor.java： 408）〜[t omcat-embed-core-9.0.21.jar：9.0.21] at org.apache.coyote.AbstractProcessorLight.process（AbstractProcessorLight.java:66）〜[tomcat-embed-core-9.0.21.jar：9.0.21 ] org.apache.coyote.AbstractProtocol $ ConnectionHandler.process（AbstractProtocol.java:853）〜[tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.tomcat.util.net.NioEndpoint $ SocketProcessor.doRun（NioEndpoint.java:1587）〜[tomcat-embed-core-9.0.21.jar：9.0.21] at org.apache.tomcat.util.net.SocketProcessorBase.run（SocketProcessorBase.java:49） 〜[tomcat-embed-core-9.0.21.jar：9.0.21]在java.base / java.base / java.base / java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1128）〜[na：na] java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:628）〜[na：na] at org.apache.tomcat.util.threads.TaskThread $ WrappingRunnable.run（TaskThread.java:61）〜[tomcat -embed-core-9.0.21.jar：9.0.21]在java.base / java.lang.Thread.run（Thread.java:835）〜[na：na]

Answer 1

1）在Document实体中添加级联到UserDocuments关系：

@OneToMany(mappedBy = "document", cascade= CascadeType.ALL)
private List<UsersDocuments> usersDocuments;

2）您需要以不同方式设置实体：

Document document = new Document(title, desc);
document.setUploadDatetime(new Date());

List<User> users = userService.getUsersByRoles(roles);

for(Use user: users){
    UserDocuments userDocuments = new UserDocuments();
    UserDocumentsId id = new UserDocumentsId();

    // Construct the Id with user and document
    id.setUser(user);
    id.setDocument(document);

    userDocuments.setDocumentsId(id);
    userDocuments.setActivtity(true);

    // This is very important for saving and cascading to work.
    document.getUserDocuments().add(userDocuments);
}

documentService.saveDocument(document);