MappingException: Named query not known

问题

Trying to learn Hibernate, i am trying to learn how to execute NamedQuries but evertime i am getting Exception in thread "main" org.hibernate.MappingException: Named query not known.Please help me out here

Error (only the message, not showing complete stack)

Exception in thread "main" org.hibernate.MappingException: Named query not known: hibernate_tut_emp.Employee.FindCountOfNames
    at org.hibernate.internal.AbstractSessionImpl.getNamedQuery(AbstractSessionImpl.java:177)
    at org.hibernate.internal.SessionImpl.getNamedQuery(SessionImpl.java:1372)
    at hibernate_tut_emp.MyOps.main(MyOps.java:20)

Employee.java

package hibernate_tut_emp;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

import javax.persistence.Table;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;



@Entity
@Table(name="Hib1")

@NamedQueries({
    @NamedQuery(name="GetDetailsByName" , query="select * from hib1 h where h.name=:name"),
    @NamedQuery(name="FindCountOfNames", query="select count(1) as cnt from hib1 h where h.name=:name")
})
public class Employee {
    private int id;
    private String name;

    @Id
    @Column(name="id")
    public int getId() {
        return id;
    }

    public void setId(int id) {
            this.id = id;
    }

    @Column(name="name")
    public String getName() {
            return name;
    }

    public void setName(String empName) {
            this.name = empName;
    }


}

MyOps.java

package hibernate_tut_emp;

import java.util.Scanner;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;

public class MyOps {

    public static void main(String[] args) {

        Scanner scnr = new Scanner(System.in);
        System.out.print("Enter a name : ");
        String name = scnr.next();

        SessionFactory ses = HibernateUtil.getSessionFactory();
        Session session = ses.openSession();

        Query query = session.getNamedQuery("hibernate_tut_emp.Employee.FindCountOfNames");


        query.setString("name", name);
        int count = ((Integer)query.iterate().next()).intValue();
        System.out.println("count : "+count);
    }
}

employee.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="hibernate_tut_emp.Employee" table="hib1">
        <id name="id" type="int" column="id">
            <generator class="native" />
        </id>
        <property name="name" type="string" column="name" />
    </class>
</hibernate-mapping>

hibernate.cfg.xml

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>
        <!-- Database connection settings -->
         <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
         <property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>
         <property name="connection.username">root</property>
         <property name="connection.password">mayank</property>

        <!-- JDBC connection pool (use the built-in) -->
         <property name="connection.pool_size">1</property>

        <!-- SQL dialect -->
         <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Enable Hibernate's automatic session context management -->
          <property name="current_session_context_class">thread</property>

        <!-- Disable the second-level cache -->
         <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout -->
         <property name="show_sql">true</property>

        <!-- Drop and re-create the database schema on startup -->
         <property name="hbm2ddl.auto">update</property>

      <mapping class="hibernate_tut_emp.Employee" />
      <mapping resource="employee.hbm.xml"/>

     </session-factory>
 </hibernate-configuration>

I googled out everything possible but i think i am overlooking some basic stuff.Any indication in right direction is appreciated! :)

One thing i considered is that if i have defined in class file NamedQueries, i do not need to mention it in xml file.Please correct me if i am wrong!

回答1:

There are several issues here:

1. Your named queries should use entities not tables. If you want native queries you should use NamedNativeQuery instead.

2. You don't need to supply the entity name when fetching the query.

   Change this:

   Query query = session.getNamedQuery("hibernate_tut_emp.Employee.FindCountOfNames");
   

   to:

   Query query = session.getNamedQuery("FindCountOfNames");
   

来源：https://stackoverflow.com/questions/26084031/mappingexception-named-query-not-known