Java 线程“main” org.hibernate.MappingException 中的异常：未知实体：
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Exception in thread "main" org.hibernate.MappingException: Unknown entity:
提问by PKK
I'm using myeclipse IDE After executing my code i'm getting the below Exception
我正在使用 myeclipse IDE 执行我的代码后，我得到以下异常
log4j:WARN No appenders could be found for logger
(org.hibernate.cfg.Environment).
log4j:WARN Please initialize the log4j system properly.
Exception in thread "main" org.hibernate.MappingException: Unknown entity:info.inetsolv.Emp
at org.hibernate.impl.SessionFactoryImpl.getEntityPersister
(SessionFactoryImpl.java:628)
at org.hibernate.impl.SessionImpl.getEntityPersister
(SessionImpl.java:1366)
at org.hibernate.engine.ForeignKeys.isTransient(ForeignKeys.java:203)
at org.hibernate.event.def.AbstractSaveEventListener.getEntityState
(AbstractSaveEventListener.java:535)
at org.hibernate.event.def.DefaultPersistEventListener.onPersist
(DefaultPersistEventListener.java:93)
at org.hibernate.event.def.DefaultPersistEventListener.onPersist
(DefaultPersistEventListener.java:61)
at org.hibernate.impl.SessionImpl.firePersist(SessionImpl.java:646)
at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:620)
at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:624)
at info.inetsolv.InsertEmprecord.main(InsertEmprecord.java:22)
POJO CLASS
POJO类
package info.inetsolv;
@SuppressWarnings("serial")
public class Emp implements java.io.Serializable {
// Fields
private Integer eno;
private String name;
private Double salary;
// Constructors
/** default constructor */
public Emp() {
}
/** minimal constructor */
public Emp(Integer eno) {
this.eno = eno;
}
/** full constructor */
public Emp(Integer eno, String name, Double salary) {
this.eno = eno;
this.name = name;
this.salary = salary;
}
// Property accessors
public Integer getEno() {
return this.eno;
}
public void setEno(Integer eno) {
this.eno = eno;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public Double getSalary() {
return this.salary;
}
public void setSalary(Double salary) {
this.salary = salary;
}
}
}
HibernateSessionFactory.java
HibernateSessionFactory.java
package info.inetsolv;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.cfg.Configuration;
public class HibernateSessionFactory {
private static final ThreadLocal<Session> threadLocal = new
ThreadLocal<Session>();
private static org.hibernate.SessionFactory sessionFactory;
private static Configuration configuration = new Configuration();
private static String CONFIG_FILE_LOCATION = "/hibernate.cfg.xml";
private static String configFile = CONFIG_FILE_LOCATION;
static {
try {
configuration.configure(configFile);
sessionFactory = configuration.buildSessionFactory();
} catch (Exception e) {
System.err.println("%%%% Error Creating SessionFactory %%%%");
e.printStackTrace();
}
}
private HibernateSessionFactory() {
}
public static Session getSession() throws HibernateException {
Session session = (Session) threadLocal.get();
if (session == null || !session.isOpen()) {
if (sessionFactory == null) {
rebuildSessionFactory();
}
session = (sessionFactory != null) ? sessionFactory.openSession(): null;
threadLocal.set(session);
}
return session;
}
public static void rebuildSessionFactory() {
try {
configuration.configure(configFile);
sessionFactory = configuration.buildSessionFactory();
} catch (Exception e) {
System.err.println("%%%% Error Creating SessionFactory %%%%");
e.printStackTrace();
}
}
public static void closeSession() throws HibernateException {
Session session = (Session) threadLocal.get();
threadLocal.set(null);
if (session != null) {
session.close();
}
}
public static org.hibernate.SessionFactory getSessionFactory() {
return sessionFactory;
}
public static void setConfigFile(String configFile) {
HibernateSessionFactory.configFile = configFile;
sessionFactory = null;
}
public static Configuration getConfiguration() {
return configuration;
}
}
}
client program to insert record into DB
将记录插入数据库的客户端程序
InsertEmprecord.java
插入Emprecord.java
package info.inetsolv;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
public class InsertEmprecord {
public static void main(String[] args) {
Configuration cfg = new Configuration();
cfg.configure();
SessionFactory sf = cfg.buildSessionFactory();
Session hsession = sf.openSession();
Transaction tx = hsession.beginTransaction();
Emp e = new Emp();
e.setEno(6);
e.setName("six");
e.setSalary(1234d);
hsession.persist(e);
tx.commit();
hsession.close();
sf.close();
}
}
And below is my hibernate mapping file Emp.hbm.xml
下面是我的休眠映射文件 Emp.hbm.xml
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD
3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="info.inetsolv.Emp" table="EMP" schema="HIB">
<id name="eno" type="java.lang.Integer">
<column name="ENO" precision="5" scale="0" />
<generator class="assigned" />
</id>
<property name="name" type="java.lang.String">
<column name="NAME" length="10" />
</property>
<property name="salary" type="java.lang.Double">
<column name="SALARY" precision="10" />
</property>
</class>
</hibernate-mapping>
AND below is my hibernate configuration file
下面是我的休眠配置文件
hibernate.cfg.xml
休眠文件.cfg.xml
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<!-- Generated by MyEclipse Hibernate Tools. -->
<hibernate-configuration>
<session-factory>
<property name="dialect">
org.hibernate.dialect.Oracle9Dialect
</property>
<property name="connection.url">
jdbc:oracle:thin:@localhost:1521:xe
</property>
<property name="connection.username">hib</property>
<property name="connection.password">abc</property>
<property name="connection.driver_class">
oracle.jdbc.driver.OracleDriver
</property>
<property name="myeclipse.connection.profile">
my oracle drive
</property>
<property name="show_sql">true</property>
</session-factory>
</hibernate-configuration>
采纳答案by Sandhu Santhakumar
You didn't configure mapping for the object Emp. The configuration file hibernate.cfg.xmlshould contain the mapping to the resource Emp.hbm.xml.
您没有为 object 配置映射Emp。配置文件hibernate.cfg.xml应包含到资源的映射Emp.hbm.xml。
<mapping resource="info/inetsolv/Emp.hbm.xml"/>
回答by Madhan Ganesh
I had similar problem for a simple Console application trying to use Hibernate. The solution I arrived to make the add the "packagesToScan" property explicitly for LocalSessionFactoryBean.
对于尝试使用 Hibernate 的简单控制台应用程序，我遇到了类似的问题。我到达的解决方案是为 LocalSessionFactoryBean 显式添加“packagesToScan”属性。
<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="packagesToScan" value="com.mg.learning.spring.orm"/> <--- this SOLVED!
<property name="hibernateProperties">
<props>
<prop key="dialect">org.hibernate.dialect.MySQL5Dialect</prop>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</prop>
</props>
</property>
</bean>
回答by Java_Explorer
@Sandhu Santakumar , answer is absolutely right.
@Sandhu Santakumar ，答案绝对正确。
Just adding the reason behind this. By default the JBoss hibernate reverse engineering tool maps class inside the mapping tab but resource attribute is the required attribute that hibernate.cfg.xml should have. class attribute is optional.
只是添加了这背后的原因。默认情况下，JBoss 休眠逆向工程工具映射映射选项卡内的类，但资源属性是 hibernate.cfg.xml 应该具有的必需属性。class 属性是可选的。
e.g. if your mapping is like this
例如，如果您的映射是这样的
resource is mandatory attribute and class is optional attribute.
资源是强制性属性，类是可选属性。
Hope this additional information helps.
希望这些附加信息有帮助。
