我最近创建了一个由Hibernate映射的新子对象，但由于某种原因它破坏了我的hibernate初始化代码，并提供了一个我似乎无法找到的null指针。
private static void init()
{
final StandardServiceRegistry registry = new StandardServiceRegistryBuilder().configure() // configures settings from hibernate.cfg.xml
.build();
MetadataSources mds = new MetadataSources(registry);
Metadata md = mds.buildMetadata();
sessionFactory = md.buildSessionFactory();
Runtime.getRuntime().addShutdownHook(new Thread(() -> {
StandardServiceRegistryBuilder.destroy(registry);
}));
}
我调试了该代码，并在Metadata md = mds.buildMetadata();上抛出了一个nullpointer，但是mds不为null。
stacktrace也指向该行。
因此，我试图保存的对象与一个对象的一对一映射，该对象具有针对新创建的类的一对多映射
最外面的对象：
@Entity
@Table(name = "movie")
public class Movie
{
@SerializedName("internal_id")
@Column(name = "movie_id")
@Id
public String internalID;
@SerializedName("image_url")
@Column(name = "image_url")
public String imageURL;
@Column(name = "title")
public String title;
@Column(name = "year")
public int year;
@OneToMany(fetch = FetchType.EAGER, cascade = {CascadeType.ALL}, mappedBy = "rating")
public List<Rating> rating = new ArrayList<>();
@SerializedName("extended_movie")
@OneToOne(fetch = FetchType.EAGER, cascade = {CascadeType.ALL})
@JoinColumn(name = "movie_id")
public ExtendedMovie extendedMovie;
@ElementCollection
@CollectionTable(name = "genre", joinColumns = @JoinColumn(name = "movie_id"))
@Column(name = "genre")
public List<String> genre = new ArrayList<>();
}
中间对象：
@Entity
@Table(name = "extended_movie")
public class ExtendedMovie
{
@Id
@OneToOne(fetch = FetchType.EAGER)
@PrimaryKeyJoinColumn
public Movie parent;
@Column(name = "description")
public String description;
@OneToMany(fetch = FetchType.EAGER, cascade = {CascadeType.ALL}, mappedBy = "starredIn", orphanRemoval = true)
public List<Cast> cast = new ArrayList<>();
@SerializedName("poster_url")
@Column(name = "poster_url")
public String posterURL;
}
leaf object：
@JsonInclude(JsonInclude.Include.NON_NULL)
@Entity
@Table(name = "cast")
public class Cast implements Serializable
{
@Id
@JsonIgnore
@ManyToOne(fetch = FetchType.EAGER, cascade = {CascadeType.ALL})
@JoinColumn(name = "movie_id")
public Movie starredIn;
@Column(name = "department")
public String department;
@Column(name = "job")
public String job;
@Column(name = "character")
public String character;
@Id
@Column(name = "name")
public String name;
@JsonProperty("profile_url")
@SerializedName("profile_url")
@Column(name = "profile_url")
public String profileURL;
}
我之前从未见过这种行为，所以我不知道从哪里开始，因为除了错误之外，nullpointer没有给我任何额外的信息。
以前有人见过这样的事吗？
堆栈跟踪：
java.lang.NullPointerException
at org.hibernate.mapping.PersistentClass.createPrimaryKey(PersistentClass.java:363)
at org.hibernate.cfg.CreateKeySecondPass.doSecondPass(CreateKeySecondPass.java:31)
at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1621)
at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1585)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:278)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
at org.hibernate.boot.MetadataSources.buildMetadata(MetadataSources.java:179)
at se.mulander.cosmos.common.database.jpa.Database.init(Database.java:38)
at se.mulander.cosmos.common.database.jpa.Database.getObjects(Database.java:151)
at se.mulander.cosmos.movies.util.Movies.lambda$getRecomendations$7(Movies.java:77)
at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1374)
at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:580)
at se.mulander.cosmos.movies.util.Movies.getRecomendations(Movies.java:71)
at se.mulander.cosmos.movies.business.Movies.getRecomendations(Movies.java:37)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory$1.invoke(ResourceMethodInvocationHandlerFactory.java:81)
at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher$1.run(AbstractJavaResourceMethodDispatcher.java:144)
at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:161)
at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$ResponseOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:160)
at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:99)
at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:389)
at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:347)
at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:102)
at org.glassfish.jersey.server.ServerRuntime$2.run(ServerRuntime.java:326)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:271)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:267)
at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
at org.glassfish.jersey.internal.Errors.process(Errors.java:267)
at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:317)
at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:305)
at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1154)
at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:473)
at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:427)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:388)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:341)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:228)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
at se.mulander.cosmos.common.swagger.ApiOriginFilter.doFilter(ApiOriginFilter.java:20)
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:670)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)