<?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>
    <!-- 数据库URL -->
    <property name="connection.url">jdbc:oracle:thin:@localhost:1521:orcl</property>
    <!-- 用户-->
    <property name="connection.username">scott</property>
    <!-- 密码 -->
    <property name="connection.password">orcl</property>
    <!-- jdbc驱动 -->
    <property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
    <!-- 每个数据库都有其对应的方言(Dialect)以匹配其平台特效 -->
    <property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>
    <!-- 指定session范围和上下文 -->
    <property name="current_session_context_class">thread</property>
    <!-- 是否将运行期间生成的SQL输出到日志以共调试 -->
    <property name="show_sql">true</property>
    <!-- 是否格式化SQL -->
    <property name="format_sql">true</property>
    <!-- 映射文件配置位置  -->
    <mapping resource="entity/EmpDao.xml"/>
  </session-factory>
</hibernate-configuration>

package entity;

import java.sql.Date;

public class Emp {
    //编号
    private Integer empno;
    //名称
    private String ename;
    //部门
    private String job;
    //上级编号
    private double MGR;
    //入职时间
    private Date hiretDate;
    //工资
    private double sal;
    //年终奖
    private double comm;
    //岗位id
    private Integer deptNo;

    public void setEmpno(Integer empno) {
        this.empno = empno;
    }

    public void setEname(String ename) {
        this.ename = ename;
    }

    public void setJob(String job) {
        this.job = job;
    }

    public void setMGR(Object MGR) {
        if (MGR!=null)
            this.MGR = (double)MGR;
    }

    public void setHiretDate(Date hiretDate) {
        this.hiretDate = hiretDate;
    }

    public void setSal(double sal) {
        this.sal = sal;
    }

    public void setComm(Object comm) {
        if(comm!=null){
            this.comm =(double)comm;
        }
    }

    public void setDeptNo(Integer deptNo) {
        this.deptNo = deptNo;
    }

    public Integer getEmpno() {
        return empno;
    }

    public String getEname() {
        return ename;
    }

    public String getJob() {
        return job;
    }

    public double getMGR() {
        return MGR;
    }

    public Date getHiretDate() {
        return hiretDate;
    }

    public double getSal() {
        return sal;
    }

    public double getComm() {
        return comm;
    }

    public Integer getDeptNo() {
        return deptNo;
    }

}

<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <!-- name实体类路径 table数据库表名 schema表的拥有者-->
    <class name="entity.Emp" table="emp" schema="scott">
        <!-- 此id属性表示 持久化的OID和表的主键映射
            name为实体类中的属性名称 type为数据类型 column为数据库中的列名 -->
        <id name="empno" type="java.lang.Integer" column="empno">
            <!-- 此属性用于指定具体注解生成策略 assigned策略,就是不使用主键生成策略,由手工输入ID. -->
            <generator class="assigned"/>
        </id>
        <!-- name为实体类中的属性名称 type为数据类型 column为数据库中的列名 not-null表示不为空与数据库列对应 -->
        <property name="ename" type="string"  not-null="true" column="ename"/>
        <property name="deptNo" type="java.lang.Integer" column="deptNo"/>
        <property name="job" type="string"column="job"/>
        <property name="MGR" type="java.lang.Double" column="MGR"/>
        <property name="hiretDate" type="java.sql.Date" column="hireDate"/>
        <property name="sal" type="java.lang.Double" column="sal"/>
        <property name="comm" type="java.lang.Double" column="comm"/>
    </class>
</hibernate-mapping>

package dao;

import entity.Emp;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

import java.io.Serializable;

public class EmpDao {
    public Emp get(Serializable id){
        //初始化配置和sessionFactory
        Configuration configuration = new Configuration().configure();
        SessionFactory sessionFactory =configuration.buildSessionFactory();
        //打开事务
        sessionFactory.getCurrentSession().beginTransaction();
        //通过session的get方法根据加载指定对象
        return (Emp)sessionFactory.getCurrentSession().get(Emp.class,id);
    }
}

package service;

import dao.EmpDao;
import entity.Emp;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

import java.io.Serializable;

public class EmpSerivce {
    EmpDao empDao =new EmpDao();
    public Emp get(Integer id){
        return empDao.get(id);
    }
}

package test;

import service.EmpSerivce;

public class Test {
    public static void main(String[] args){
        EmpSerivce empSerivce = new EmpSerivce();
        System.out.println(empSerivce.get(7788).getEname());
    }
}