java无法访问实体类中的字段
我正在尝试创建一个示例EAR、maven项目，我几乎所有的东西都在工作，但由于某种原因，我的entity类存在一个问题。在我的数据库中，我有一个多对一的关系，尝试将列与实体类中的另一个表连接起来是一件痛苦的事情。我找了一段时间，但什么都没找到。我希望在这方面能得到一些帮助
import java.io.Serializable;
import javax.persistence.*;
/**
* The persistent class for the "city" database table.
*
*/
@Entity
@Table(name="\"city\"")
@NamedQuery(name="City.findAll", query="SELECT c FROM City c")
public class City extends com.dozie.example.util.Entity implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="\"id\"")
private Integer id;
@Column(name="\"country_id\"")
private int countryId;
@Column(name="\"name\"")
private String name;
//bi-directional many-to-one association to Country
@ManyToOne
@JoinColumns({
@JoinColumn(name="\"country_id\"", referencedColumnName="\"id\"")
})
private Country country;
public City() {
}
public Integer getId() {
return this.id;
}
public void setId(Integer id) {
this.id = id;
}
public int getCountryId() {
return this.countryId;
}
public void setCountryId(int countryId) {
this.countryId = countryId;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public Country getCountry() {
return this.country;
}
public void setCountry(Country country) {
this.country = country;
}
}
还有我的另一个实体类
import java.io.Serializable;
import javax.persistence.*;
import java.util.Set;
/**
* The persistent class for the "country" database table.
*
*/
@Entity
@Table(name="\"country\"")
@NamedQuery(name="Country.findAll", query="SELECT c FROM Country c")
public class Country extends com.dozie.example.util.Entity implements Serializable {
private static final long serialVersionUID = 1L;
private Integer id;
private String name;
private Set<City> cities;
public Country() {
}
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="\"id\"")
public Integer getId() {
return this.id;
}
public void setId(Integer id) {
this.id = id;
}
@Column(name="\"name\"")
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
//bi-directional many-to-one association to City
@OneToMany(mappedBy="country")
public Set<City> getCities() {
return this.cities;
}
public void setCities(Set<City> cities) {
this.cities = cities;
}
public City addCity(City city) {
getCities().add(city);
city.setCountry(this);
return city;
}
public City removeCity(City city) {
getCities().remove(city);
city.setCountry(null);
return city;
}
}
这是我的数据库表的脚本，这是一个Postgres数据库
CREATE TABLE city
(
id integer NOT NULL,
country_id integer NOT NULL,
name character varying(30) NOT NULL,
CONSTRAINT city_pk PRIMARY KEY (id),
CONSTRAINT city_country_fk FOREIGN KEY (country_id)
REFERENCES country (id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE CASCADE,
CONSTRAINT city_name_idx UNIQUE (name)
)
CREATE TABLE country
(
id integer NOT NULL,
name character varying(10) NOT NULL,
CONSTRAINT country_pk PRIMARY KEY (id),
CONSTRAINT country_name_idx UNIQUE (name)
)
当我的服务器运行时，我收到这个错误消息
javax.persistence.PersistenceException: [PersistenceUnit: cookbook-entities] Unable to build EntityManagerFactory at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:915) at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:890) at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:74) at org.glassfish.persistence.jpa.PersistenceUnitLoader.loadPU(PersistenceUnitLoader.java:206) at org.glassfish.persistence.jpa.PersistenceUnitLoader.(PersistenceUnitLoader.java:120) at org.glassfish.persistence.jpa.JPADeployer$1.visitPUD(JPADeployer.java:224) at org.glassfish.persistence.jpa.JPADeployer$PersistenceUnitDescriptorIterator.iteratePUDs(JPADeployer.java:495) at org.glassfish.persistence.jpa.JPADeployer.createEMFs(JPADeployer.java:233) at org.glassfish.persistence.jpa.JPADeployer.prepare(JPADeployer.java:168) at com.sun.enterprise.v3.server.ApplicationLifecycle.prepareModule(ApplicationLifecycle.java:871) at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:410) at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:240) at org.glassfish.deployment.admin.DeployCommand.execute(DeployCommand.java:389) at com.sun.enterprise.v3.admin.CommandRunnerImpl$1.execute(CommandRunnerImpl.java:348) at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:363) at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:1085) at com.sun.enterprise.v3.admin.CommandRunnerImpl.access$1200(CommandRunnerImpl.java:95) at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1291) at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1259) at com.sun.enterprise.v3.admin.AdminAdapter.doCommand(AdminAdapter.java:461) at com.sun.enterprise.v3.admin.AdminAdapter.service(AdminAdapter.java:212) at com.sun.grizzly.tcp.http11.GrizzlyAdapter.service(GrizzlyAdapter.java:179) at com.sun.enterprise.v3.server.HK2Dispatcher.dispath(HK2Dispatcher.java:117) at com.sun.enterprise.v3.services.impl.ContainerMapper$Hk2DispatcherCallable.call(ContainerMapper.java:354) at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195) at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:849) at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:746) at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1045) at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:228) at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90) at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79) at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54) at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59) at com.sun.grizzly.ContextTask.run(ContextTask.java:71) at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532) at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513) at java.lang.Thread.run(Thread.java:722) Caused by: org.hibernate.MappingException: Unable to find column with logical name: "id" in org.hibernate.mapping.Table(country) and its related supertables and secondary tables at org.hibernate.cfg.Ejb3JoinColumn.checkReferencedColumnsType(Ejb3JoinColumn.java:552) at org.hibernate.cfg.BinderHelper.createSyntheticPropertyReference(BinderHelper.java:257) at org.hibernate.cfg.ToOneFkSecondPass.doSecondPass(ToOneFkSecondPass.java:116) at org.hibernate.cfg.Configuration.processEndOfQueue(Configuration.java:1521) at org.hibernate.cfg.Configuration.processFkSecondPassInOrder(Configuration.java:1446) at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1351) at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1733) at org.hibernate.ejb.EntityManagerFactoryImpl.(EntityManagerFactoryImpl.java:94) at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:905) ... 38 more
当我尝试更新City实体中的join列以不包含referenceColumnName时，我会收到另一个错误，即物理名称与逻辑名称不同。 我还注意到，在实体类中，我不能在不将字段加引号的情况下命名字段（我不知道这是否是一种正常行为），我认为这可能与我的问题有关，但我尝试过不加引号，每当发生这种情况时，我都会出错
如果能帮上忙，我将不胜感激
# 1 楼答案
你到处都加了双引号。你不应该，比如
应该是
及
应该是
及
应该只是