I've got 5 files 3 xml and 2 java (to connect and execute HQL query),
hibernate.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">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://host:3306/wwwgeeksearthcom_geeksearth_test</property>
<property name="hibernate.connection.username">username</property>
<property name="hibernate.connection.password">******</property>
<property name="hibernate.show_sql">true</property>
<mapping resource="hibernate.hbm.xml"/>
</session-factory>
</hibernate-configuration>
hibernate.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 package="client">
<class name="HiberTest" table="guests">
<id name="id" column="g_id">
<generator class="native"/>
</id>
</class>
</hibernate-mapping>
hibernate.hbm.xml
&l开发者_运维问答t;?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-reverse-engineering PUBLIC "-//Hibernate/Hibernate Reverse Engineering DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-reverse-engineering-3.0.dtd">
<hibernate-reverse-engineering>
<schema-selection match-catalog="wwwgeeksearthcom_geeksearth_test"/>
<table-filter match-name="guests"/>
</hibernate-reverse-engineering>
HiberTest.java
import org.hibernate.*;
import org.hibernate.cfg.*;
import java.util.*;
public class HiberTest {
private static SessionFactory sessionFactory;
private int id;
protected static void setUp() throws Exception {
// A SessionFactory is set up once for an application
sessionFactory = new Configuration()
.configure() // configures settings from hibernate.cfg.xml
.buildSessionFactory();
}
public static void main(String[] args) throws Exception {
setUp();
Session session = HibernateUtil.getSessionFactory().openSession();
session.beginTransaction();
Query q = session.createQuery("from guests");
List resultList = q.list();
System.out.println(resultList);
session.getTransaction().commit();
session.close();
}
}
HibernateUtil.java
import org.hibernate.cfg.*;
import org.hibernate.SessionFactory;
/**
* Hibernate Utility class with a convenient method to get Session Factory object.
*
* @author arthurkushman
*/
public class HibernateUtil {
private static final SessionFactory sessionFactory = buildSessionFactory();
private static SessionFactory buildSessionFactory() {
try {
// Create the SessionFactory from hibernate.cfg.xml
return new Configuration().configure().buildSessionFactory();
}
catch (Throwable ex) {
// Make sure you log the exception, as it might be swallowed
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}
The error:
Exception in thread "main" org.hibernate.hql.ast.QuerySyntaxException: guests is not mapped [from guests]
at org.hibernate.hql.ast.util.SessionFactoryHelper.requireClassPersister(SessionFactoryHelper.java:158)
at org.hibernate.hql.ast.tree.FromElementFactory.addFromElement(FromElementFactory.java:87)
at org.hibernate.hql.ast.tree.FromClause.addFromElement(FromClause.java:70)
at org.hibernate.hql.ast.HqlSqlWalker.createFromElement(HqlSqlWalker.java:255)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.fromElement(HqlSqlBaseWalker.java:3056)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.fromElementList(HqlSqlBaseWalker.java:2945)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.fromClause(HqlSqlBaseWalker.java:688)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:544)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:281)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:229)
at org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:228)
at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:160)
at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:111)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:77)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:56)
at org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:72)
at org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:133)
at org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:112)
at org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1623)
at HiberTest.main(HiberTest.java:27)
Java Result: 1
HQL queries should specify the entity class, not the table name.
Looking at your mapping, that means "from HiberTest"
, instead of "from guests"
.
Having said that, your example makes no sense. The class
specified in the mapping should refer to a persistent entity class (e.g. Guest
), which is mapped to your guests
database table. Your HiberTest
class is a piece of test logic, and has nothing to do with the mapping.
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