第一次尝试从头开始使用Hibernate。 我有实体类：
package centaurus.domain;
import javax.persistence.*;
@Entity
@Table(name="users")
public class Player {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name="USER_ID")
private int id;
@Column(name="email")
private String email;
public Player(){};
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public void setId(int id) {
this.id = id;
}
public int getId() {
return id;
}
}
DAOimpl： 包centaurus.service;
import centaurus.domain.Player;
import restx.factory.Component;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.SessionFactory;
@Component
public class PlayerDAOimpl implements PlayerDAO{
private static SessionFactory factory;
public PlayerDAOimpl() {
try{
factory = new Configuration().
configure().addAnnotatedClass(Player.class).
buildSessionFactory();
//
}catch (Throwable ex) {
System.err.println("Failed to create sessionFactory object." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public Player savePlayer(Player player){
Session session = factory.openSession();
Transaction tx = null;
Integer playerID = null;
try{
tx = session.beginTransaction();
playerID = (Integer) session.save(player);
tx.commit();
}catch (HibernateException e) {
if (tx!=null) tx.rollback();
e.printStackTrace();
}finally {
session.close();
}
return player;
}
public Player getPlayer(Integer playerId){
Session session = factory.openSession();
try{
Player player = (Player)session.get(Player.class, playerId);
return player;
}catch (HibernateException e) {
}finally {
session.close();
}
return null;
}
}
演示错误我让它在startupscript上添加了一个播放器。
和错误：
-- RESTX >> LOAD ON REQUEST << >> DEV MODE << >> AUTO COMPILE <<
-- for admin console,
-- VISIT http://127.0.0.1:9091/api/@/ui/
--
2016-05-31 21:42:48,901 [main ] [ ] INFO restx.Apps - can't enable Apidocs doclet: make sure tools.jar is in your classpath
2016-05-31 21:42:49,978 [pool-1-thread-1 ] [ ] INFO restx.classloader.CompilationManager - compilation finished: 12 sources compiled in 1.015 s
2016-05-31 21:42:50,061 [main ] [ ] INFO restx.Apps - can't enable Apidocs doclet: make sure tools.jar is in your classpath
2016-05-31 21:42:50,078 [main ] [ ] INFO restx.classloader.CompilationManager - watching for changes in [src/main/java, src/main/resources]; current location is /home/arthur/elorhia/api/.
2016-05-31 21:42:50,145 [main ] [ ] INFO org.hibernate.Version - HHH000412: Hibernate Core {5.1.0.Final}
2016-05-31 21:42:50,146 [main ] [ ] INFO org.hibernate.cfg.Environment - HHH000206: hibernate.properties not found
2016-05-31 21:42:50,147 [main ] [ ] INFO org.hibernate.cfg.Environment - HHH000021: Bytecode provider name : javassist
2016-05-31 21:42:50,802 [main ] [ ] INFO o.h.annotations.common.Version - HCANN000001: Hibernate Commons Annotations {5.0.1.Final}
2016-05-31 21:42:50,851 [main ] [ ] WARN org.hibernate.orm.connections - HHH10001002: Using Hibernate built-in connection pool (not for production use!)
2016-05-31 21:42:50,856 [main ] [ ] INFO org.hibernate.orm.connections - HHH10001005: using driver [com.mysql.jdbc.Driver] at URL [jdbc:mysql://localhost/andromeda]
2016-05-31 21:42:50,857 [main ] [ ] INFO org.hibernate.orm.connections - HHH10001001: Connection properties: {user=api, password=****}
2016-05-31 21:42:50,858 [main ] [ ] INFO org.hibernate.orm.connections - HHH10001003: Autocommit mode: false
2016-05-31 21:42:50,860 [main ] [ ] INFO o.h.e.j.c.i.DriverManagerConnectionProviderImpl - HHH000115: Hibernate connection pool size: 1 (min=1)
2016-05-31 21:42:51,090 [main ] [ ] INFO org.hibernate.dialect.Dialect - HHH000400: Using dialect: org.hibernate.dialect.MySQLDialect
2016-05-31 21:42:51,321 [main ] [ ] INFO o.h.validator.internal.util.Version - HV000001: Hibernate Validator 5.0.1.Final
START SCRIPT!
org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private java.lang.String centaurus.domain.Player.email] by reflection for persistent property [centaurus.domain.Player#email] : centaurus.domain.Player@507b79f7
at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:43)
at org.hibernate.property.access.spi.GetterFieldImpl.getForInsert(GetterFieldImpl.java:58)
at org.hibernate.tuple.entity.AbstractEntityTuplizer.getPropertyValuesToInsert(AbstractEntityTuplizer.java:521)
at org.hibernate.tuple.entity.PojoEntityTuplizer.getPropertyValuesToInsert(PojoEntityTuplizer.java:228)
at org.hibernate.persister.entity.AbstractEntityPersister.getPropertyValuesToInsert(AbstractEntityPersister.java:4701)
at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:254)
at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:182)
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:113)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:192)
at org.hibernate.event.internal.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:38)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:177)
at org.hibernate.event.internal.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:32)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:73)
at org.hibernate.internal.SessionImpl.fireSave(SessionImpl.java:682)
at org.hibernate.internal.SessionImpl.save(SessionImpl.java:674)
at org.hibernate.internal.SessionImpl.save(SessionImpl.java:669)
at centaurus.service.PlayerDAOimpl.savePlayer(PlayerDAOimpl.java:39)
at centaurus.Dbmaintain.start(Dbmaintain.java:26)
at restx.factory.Factory.start(Factory.java:846)
at restx.RestxMainRouterFactory.build(RestxMainRouterFactory.java:450)
at restx.RestxMainRouterFactory.newInstance(RestxMainRouterFactory.java:70)
at restx.servlet.RestxMainRouterServlet.init(RestxMainRouterServlet.java:74)
at org.eclipse.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:519)
at org.eclipse.jetty.servlet.ServletHolder.doStart(ServletHolder.java:331)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
at org.eclipse.jetty.servlet.ServletHandler.initialize(ServletHandler.java:747)
at org.eclipse.jetty.servlet.ServletContextHandler.startContext(ServletContextHandler.java:265)
at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1250)
at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:706)
at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:492)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
at org.eclipse.jetty.server.handler.HandlerCollection.doStart(HandlerCollection.java:229)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
at org.eclipse.jetty.server.handler.HandlerCollection.doStart(HandlerCollection.java:229)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:95)
at org.eclipse.jetty.server.Server.doStart(Server.java:277)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
at restx.server.JettyWebServer.start(JettyWebServer.java:109)
at restx.server.JettyWebServer.startAndAwait(JettyWebServer.java:114)
at centaurus.AppServer.main(AppServer.java:30)
Caused by: java.lang.IllegalArgumentException: Can not set java.lang.String field centaurus.domain.Player.email to centaurus.domain.Player
at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:167)
at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:171)
at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:58)
at sun.reflect.UnsafeObjectFieldAccessorImpl.get(UnsafeObjectFieldAccessorImpl.java:36)
at java.lang.reflect.Field.get(Field.java:393)
at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:39)
... 40 more
2016-05-31 21:42:51,673 [main ] [ ] INFO restx.monitor.MetricsConfiguration - registering Metrics JVM metrics
2016-05-31 21:44:41,646 [pool-2-thread-1 ] [ ] INFO restx.classloader.CompilationManager - compilation finished: 1 sources compiled in 86.94 ms
看起来它试图将电子邮件字段设置为播放器对象。 我无法解决原因！我做错了什么？
编辑：根据要求我添加了创建播放器的代码并调用dao
package centaurus;
import centaurus.domain.Player;
import centaurus.service.PlayerDAO;
import centaurus.service.PlayerDAOimpl;
import restx.factory.AutoStartable;
import restx.factory.Component;
import javax.inject.Named;
@Component
public class Dbmaintain implements AutoStartable{
private PlayerDAO playerDAO;
public Dbmaintain(@Named("PlayerDAOimpl") PlayerDAO playerDAO) {
this.playerDAO = playerDAO;
}
public void start(){
System.out.println("START SCRIPT!");
//test
Player p = new Player();
p.setEmail("test");
playerDAO.savePlayer(p);
try {
// URL configurationUrl = new File("dbmaintain.properties").toURI().toURL();
// MainFactory mainFactory = new MainFactory(configurationUrl);
// DbMaintainer dbMaintainer = mainFactory.createDbMaintainer();
// dbMaintainer.updateDatabase(false);
} catch(Exception e) {
}
}
}
如果人们想要其他位，请编辑添加的git链接： https://github.com/ArthurGibbs/Centaurus-
答案 0 :(得分：0)
您如何设置/创建Player？
Caused by: java.lang.IllegalArgumentException: Can not set java.lang.String field centaurus.domain.Player.email to centaurus.domain.Player
这就是说，尝试将类centaurus.domain.Player的对象存储到String字段中。有关进一步说明，请附上正在修改/创建播放器的实际代码，并将其传递给DAO
答案 1 :(得分：0)
我使用了你的确切类Player来执行这段代码并且完全没有错误。正确地在表USERS中插入一行。
public class TestPlayer {
public static void main(String[] args) {
EntityManagerFactory emf = Persistence.createEntityManagerFactory("TestDB");
EntityManager em = emf.createEntityManager();
Session session = (Session) em.getDelegate();
Transaction tx = session.beginTransaction();
try {
Player p = new Player();
p.setEmail("email");
session.save(p);
tx.commit();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
em.close();
emf.close();
}
}
}
问题不在实体类中。也许您所做的某些更改在部署时无法正确刷新。