Hibernate 使用HQL做查询，hibernatehql,package cn.o

Hibernate 使用HQL做查询，hibernatehql,package cn.o

package cn.outofmemory.snippets.enterprise;import java.util.List;import org.hibernate.HibernateException;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.cfg.Configuration;public class RetrieveObjectsInHibernateWithHQLQuery {    @SuppressWarnings("unchecked")    public static void main(String[] args) {        SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();        Session session = sessionFactory.getCurrentSession();        try {            session.beginTransaction();            List<Employee> employees = (List<Employee>) session.createQuery("from Employee").list();            if (employees!=null) {                for (Employee employee : employees) {                    System.out.println(employee.getId() + " - " + employee.getName());                }            }            session.getTransaction().commit();        }        catch (HibernateException e) {            e.printStackTrace();            session.getTransaction().rollback();        }    }}

package cn.outofmemory.snippets.enterprise;import java.util.Date;public class Employee {    private Long id;    private String name;    private String surname;    private String title;    private Date created;    public Long getId() {        return id;    }    public void setId(Long id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getSurname() {        return surname;    }    public void setSurname(String surname) {        this.surname = surname;    }    public String getTitle() {        return title;    }    public void setTitle(String title) {        this.title = title;    }    public Date getCreated() {        return created;    }    public void setCreated(Date created) {        this.created = created;    }}

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>        <!-- JDBC connection settings -->        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>        <property name="connection.url">jdbc:mysql://localhost/companydb</property>        <property name="connection.username">jcg</property>        <property name="connection.password">jcg</property>        <!-- JDBC connection pool, use Hibernate internal connection pool -->        <property name="connection.pool_size">5</property>        <!-- Defines the SQL dialect used in Hiberante's application -->        <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>        <!-- Display and format all executed SQL to stdout -->        <property name="show_sql">true</property>        <property name="format_sql">true</property>        <!-- Drop and re-create the database schema on startup -->        <property name="hbm2ddl.auto">update</property>        <!-- Mapping to hibernate mapping files -->        <mapping resource="Employee.hbm.xml" />    </session-factory></hibernate-configuration>

Employee.hbm.xml

<?xml version="1.0"?><!DOCTYPE hibernate-mapping PUBLIC        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"        "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"><hibernate-mapping>    <class name="cn.outofmemory.snippets.enterprise.Employee" table="employee">        <id name="id" column="id">            <generator class="native"/>        </id>        <property name="name" not-null="true" length="50" />        <property name="surname" not-null="true" length="50" />        <property name="title" length="50" />        <property name="created" type="timestamp" />    </class></hibernate-mapping>

CREATE TABLE `companydb`.`employee` (  `id` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT,  `name` VARCHAR(45) NOT NULL,  `surname` VARCHAR(45) NOT NULL,  `title` VARCHAR(45) NOT NULL,  `created` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,  PRIMARY KEY (`id`));

输出：

Hibernate:     select        employee0_.id as id0_,        employee0_.name as name0_,        employee0_.surname as surname0_,        employee0_.title as title0_,        employee0_.created as created0_     from        employee employee0_2 - Tom3 - Jack