spring-boot - 我如何使用注释将3个类彼此连接？（JPA / Spring-Boot）

@Entity @Table(name = "tweet") public class Tweet { @Id @Column(name = "ID") @GeneratedValue private long id; private String tweetID; private String parentTweetID; private String avatar; private String owner_name; private String owner_nick; private String content; private String sent_time; private String sent_date; private String retweet_count; private String like_count; private String owner_link; @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "thread_id") private Thread thread; @OneToMany(fetch = FetchType.LAZY,mappedBy = "tweet") private List<Media> mediaURLs; ....(getter/setter) }

@Entity public class Thread { @Id @Column(name = "ID") @GeneratedValue private Long id; @OneToMany(fetch = FetchType.LAZY,mappedBy = "thread") private List<Tweet> listOfTweets; .....(getter/setter) }

@Entity @Table(name="media") public class Media { @Id @Column(name = "ID") @GeneratedValue private long id; private String mediaID; private String mediaType; private String mediaUrl; private String mediaUrlHttps; private String mediaVideoUrl; @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "tweetID") private Tweet tweet; .....(getter/setter) }

spring.datasource.url=jdbc:mysql://localhost:3306/tweetdb?useUnicode=true&characterEncoding=utf8&useSSL=false spring.datasource.username=tweet spring.datasource.password=root spring.datasource.driver-class-name=com.mysql.jdbc.Driver spring.jpa.show-sql=true spring.jpa.hibernate.ddl-auto=update spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect spring.thymeleaf.templates_root=src/main/resources/templates/ logging.level.org.springframework.web= DEBUG logging.level.com.savetweet= DEBUG logging.level.org.hibernate= ERROR

2019-02-10 21:09:03.662 INFO 7080 --- [ restartedMain] com.savetweet.tweet.TweetApplication : Starting TweetApplication on DESKTOP-ND86E11 with PID 7080 (C:\Users\iko\Desktop\tweet\target\classes started by iko in C:\Users\iko\Desktop\tweet) 2019-02-10 21:09:03.668 DEBUG 7080 --- [ restartedMain] com.savetweet.tweet.TweetApplication : Running with Spring Boot v2.1.2.RELEASE, Spring v5.1.4.RELEASE 2019-02-10 21:09:03.669 INFO 7080 --- [ restartedMain] com.savetweet.tweet.TweetApplication : No active profile set, falling back to default profiles: default WARNING: An illegal reflective access operation has occurred WARNING: Illegal reflective access by org.codehaus.groovy.vmplugin.v7.Java7$1 (file:/C:/Users/iko/.m2/repository/org/codehaus/groovy/groovy/2.5.5/groovy-2.5.5.jar) to constructor java.lang.invoke.MethodHandles$Lookup(java.lang.Class,int) WARNING: Please consider reporting this to the maintainers of org.codehaus.groovy.vmplugin.v7.Java7$1 WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations WARNING: All illegal access operations will be denied in a future release 2019-02-10 21:09:04.037 INFO 7080 --- [ restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable 2019-02-10 21:09:04.037 INFO 7080 --- [ restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG' 2019-02-10 21:09:05.035 INFO 7080 --- [ restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data repositories in DEFAULT mode. 2019-02-10 21:09:05.125 INFO 7080 --- [ restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 79ms. Found 1 repository interfaces. 2019-02-10 21:09:05.680 INFO 7080 --- [ restartedMain] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration' of type [org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration$$EnhancerBySpringCGLIB$$5fbd0686] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying) 2019-02-10 21:09:06.245 INFO 7080 --- [ restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http) 2019-02-10 21:09:06.292 INFO 7080 --- [ restartedMain] o.apache.catalina.core.StandardService : Starting service [Tomcat] 2019-02-10 21:09:06.292 INFO 7080 --- [ restartedMain] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.14] 2019-02-10 21:09:06.303 INFO 7080 --- [ restartedMain] o.a.catalina.core.AprLifecycleListener : The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: [C:\Program Files\Java\jdk-9.0.4\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\ProgramData\DockerDesktop\version-bin;C:\Program Files\Docker\Docker\Resources\bin;C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\ProgramData\Oracle\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\Skype\Phone\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program Files (x86)\GtkSharp\2.12\bin;C:\Program Files\nodejs\;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files\dotnet\;C:\Program Files\Java\jdk-9.0.4\bin;C:\Program Files\Java\jdk-9.0.4\bin;C:\Program Files\apache-maven-3.5.2;C:\Program Files\apache-maven-3.5.2\bin;C:\Program Files (x86)\Microsoft Emulator Manager\1.0\;C:\Program Files\PuTTY\;C:\Program Files\Microsoft SQL Server\130\Tools\Binn\;C:\Program Files\Microsoft SQL Server\Client SDK\ODBC\130\Tools\Binn\;C:\Program Files (x86)\Microsoft SQL Server\140\Tools\Binn\;C:\Program Files\Microsoft SQL Server\140\Tools\Binn\;C:\Program Files\Microsoft SQL Server\140\DTS\Binn\;C:\Program Files (x86)\Microsoft SQL Server\Client SDK\ODBC\130\Tools\Binn\;C:\Program Files (x86)\Microsoft SQL Server\140\DTS\Binn\;C:\Program Files (x86)\Microsoft SQL Server\140\Tools\Binn\ManagementStudio\;C:\Users\iko\Desktop\TensorFlow\bazel;C:\WINDOWS\System32\OpenSSH\;C:\Program Files\Git\cmd;C:\Program Files\Git\mingw64\bin;C:\Program Files\Git\usr\bin;C:\Users\iko\AppData\Local\Microsoft\WindowsApps;C:\Program Files (x86)\Microsoft VS Code\bin;C:\Users\iko\AppData\Roaming\npm;C:\Users\iko\AppData\Local\Programs\Fiddler;C:\Users\iko\Desktop\TensorFlow\bazel;C:\Users\iko\Desktop\TensorFlow\bazel.exe;;%USERPROFILE%\AppData\Local\Microsoft\WindowsApps;.] 2019-02-10 21:09:06.487 INFO 7080 --- [ restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext 2019-02-10 21:09:06.487 DEBUG 7080 --- [ restartedMain] o.s.web.context.ContextLoader : Published root WebApplicationContext as ServletContext attribute with name [org.springframework.web.context.WebApplicationContext.ROOT] 2019-02-10 21:09:06.487 INFO 7080 --- [ restartedMain] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 2450 ms Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary. 2019-02-10 21:09:06.682 INFO 7080 --- [ restartedMain] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Starting... 2019-02-10 21:09:06.686 WARN 7080 --- [ restartedMain] com.zaxxer.hikari.util.DriverDataSource : Registered driver with driverClassName=com.mysql.jdbc.Driver was not found, trying direct instantiation. 2019-02-10 21:09:06.883 INFO 7080 --- [ restartedMain] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Start completed. 2019-02-10 21:09:08.537 ERROR 7080 --- [ restartedMain] o.h.engine.jdbc.spi.SqlExceptionHelper : null 2019-02-10 21:09:08.547 WARN 7080 --- [ restartedMain] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.exception.GenericJDBCException: Unable to open JDBC Connection for DDL execution 2019-02-10 21:09:08.549 INFO 7080 --- [ restartedMain] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Shutdown initiated... 2019-02-10 21:09:08.562 INFO 7080 --- [ restartedMain] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Shutdown completed. 2019-02-10 21:09:08.565 INFO 7080 --- [ restartedMain] o.apache.catalina.core.StandardService : Stopping service [Tomcat] 2019-02-10 21:09:08.578 INFO 7080 --- [ restartedMain] ConditionEvaluationReportLoggingListener : Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled. 2019-02-10 21:09:08.593 ERROR 7080 --- [ restartedMain] o.s.boot.SpringApplication : Application run failed org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.exception.GenericJDBCException: Unable to open JDBC Connection for DDL execution at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1745) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:576) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:498) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1083) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:853) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:546) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) ~[spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE] at com.savetweet.tweet.TweetApplication.main(TweetApplication.java:35) [classes/:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na] at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na] at java.base/java.lang.reflect.Method.invoke(Method.java:564) ~[na:na] at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-2.1.2.RELEASE.jar:2.1.2.RELEASE] Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.exception.GenericJDBCException: Unable to open JDBC Connection for DDL execution at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:402) ~[spring-orm-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:377) ~[spring-orm-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341) ~[spring-orm-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1804) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1741) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE] ... 21 common frames omitted Caused by: org.hibernate.exception.GenericJDBCException: Unable to open JDBC Connection for DDL execution at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:47) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:113) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:99) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.resource.transaction.backend.jdbc.internal.DdlTransactionIsolatorNonJtaImpl.getIsolatedConnection(DdlTransactionIsolatorNonJtaImpl.java:69) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.internal.exec.ImprovedExtractionContextImpl.getJdbcConnection(ImprovedExtractionContextImpl.java:60) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.internal.exec.ImprovedExtractionContextImpl.getJdbcDatabaseMetaData(ImprovedExtractionContextImpl.java:67) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.getTables(InformationExtractorJdbcDatabaseMetaDataImpl.java:329) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.extract.internal.DatabaseInformationImpl.getTablesInformation(DatabaseInformationImpl.java:120) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.internal.GroupedSchemaMigratorImpl.performTablesMigration(GroupedSchemaMigratorImpl.java:65) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.performMigration(AbstractSchemaMigrator.java:207) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.internal.AbstractSchemaMigrator.doMigration(AbstractSchemaMigrator.java:114) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.performDatabaseAction(SchemaManagementToolCoordinator.java:183) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.process(SchemaManagementToolCoordinator.java:72) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:310) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:467) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:939) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:57) ~[spring-orm-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.1.4.RELEASE.jar:5.1.4.RELEASE] at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:390) ~[spring-orm-5.1.4.RELEASE.jar:5.1.4.RELEASE] ... 25 common frames omitted Caused by: java.sql.SQLFeatureNotSupportedException: null at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:135) ~[HikariCP-3.2.0.jar:na] at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator$ConnectionProviderJdbcConnectionAccess.obtainConnection(JdbcEnvironmentInitiator.java:180) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] at org.hibernate.resource.transaction.backend.jdbc.internal.DdlTransactionIsolatorNonJtaImpl.getIsolatedConnection(DdlTransactionIsolatorNonJtaImpl.java:43) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final] ... 40 common frames omitted