Hibernate-简单的crud案例

一.导包

二.写总配置文件 hibernate.cfg.xml

<!DOCTYPE hibernate-configuration PUBLIC    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"    "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"><hibernate-configuration>    <session-factory>         <!--数据库连接配置-->        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>        <property name="hibernate.connection.url">jdbc:mysql:///learnstruts</property>        <property name="hibernate.connection.username">root</property>        <property name="hibernate.connection.password">33269456.cx</property>        <property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>        <property name="hibernate.show_sql">true</property>        <!--加载所有映射-->        <mapping resource="com/cx/hello/Employee.hbm.xml"></mapping>    </session-factory></hibernate-configuration>

三.写entity类

package com.cx.hello;import java.util.Date;/** * Created by cxspace on 16-7-16. */public class Employee {    private int empId;    private String empName;    private Date workDate;    public int getEmpId() {        return empId;    }    public void setEmpId(int empId) {        this.empId = empId;    }    public String getEmpName() {        return empName;    }    public void setEmpName(String empName) {        this.empName = empName;    }    public Date getWorkDate() {        return workDate;    }    public void setWorkDate(Date workDate) {        this.workDate = workDate;    }    @Override    public String toString() {        return "Employee{" +                "empId=" + empId +                ", empName='" + empName + '\'' +                ", workDate=" + workDate +                '}';    }}

四,编写对象关系配置文件  Employee.hbm.xml

<?xml version="1.0"?><!DOCTYPE hibernate-mapping PUBLIC        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"        "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><hibernate-mapping package="com.cx.hello">    <class name="Employee" table="employee">        <!--对象与表,字段与属性-->        <!--主键,映射-->        <id name="empId" column="id">            <generator class="native"/>        </id>        <!--非主键,映射-->        <property name="empName" column="empName" ></property>        <property name="workDate" column="workDate"></property>    </class></hibernate-mapping>

五.编写接口com.cx.crud.IEmployeeDao

package com.cx.crud;import com.cx.hello.Employee;import java.io.Serializable;import java.util.List;/** * Created by cxspace on 16-7-19. */public interface IEmployeeDao {    void save(Employee emp);    void update(Employee emp);    Employee findById(Serializable id);    List<Employee> getAll();    List<Employee> getAll(String employeeName);    List<Employee> getAll(int index , int count);    void delete(Serializable id);}

六.编写实现

package com.cx.crud;import com.cx.hello.Employee;import com.cx.utils.HibernateUtils;import org.hibernate.Query;import org.hibernate.Session;import org.hibernate.Transaction;import java.io.Serializable;import java.util.List;/** * Created by cxspace on 16-7-19. */public class EmployeeDao implements IEmployeeDao {    @Override    public void save(Employee emp) {        Session session = null;        Transaction tx = null;        try {            //获取session            session = HibernateUtils.getSession();            //开启事务            tx = session.beginTransaction();            //执行保存操作            session.save(emp);        } catch (Exception e){            throw new RuntimeException(e);        }finally {            tx.commit();            session.close();        }    }    @Override    public void update(Employee emp) {        Session session = null;        Transaction tx = null;        try {            //获取session            session = HibernateUtils.getSession();            //开启事务            tx = session.beginTransaction();            session.update(emp);        } catch (Exception e){            throw new RuntimeException(e);        }finally {            tx.commit();            session.close();        }    }    @Override    public Employee findById(Serializable id) {        Session session = null;        Transaction tx = null;        try {            //获取session             session = HibernateUtils.getSession();            //开启事务             tx = session.beginTransaction();            //主键查询            return (Employee) session.get(Employee.class, id);        } catch (Exception e){            throw new RuntimeException(e);        }finally {            tx.commit();            session.close();        }    }    @Override    public List<Employee> getAll() {        Session session = null;        Transaction tx = null;        try {            session = HibernateUtils.getSession();            tx = session.beginTransaction();            //HQL查询            Query q = session.createQuery("from Employee");            return q.list();        }catch (Exception e){            throw new RuntimeException(e);        }finally {            tx.commit();            session.close();        }    }    @Override    public List<Employee> getAll(String employeeName) {        Session session = null;        Transaction tx = null;        try {            session = HibernateUtils.getSession();            tx = session.beginTransaction();            Query q = session.createQuery("from Employee where empName = ?");             //下标必须从0开始            q.setParameter(0,employeeName);            //执行这行开始查询            return q.list();        }catch (Exception e){            throw new RuntimeException(e);        }finally {            tx.commit();            session.close();        }    }    @Override    public List<Employee> getAll(int index, int count) {        Session session = null;        Transaction tx = null;        try {            session = HibernateUtils.getSession();            tx = session.beginTransaction();            Query q = session.createQuery("from Employee ");            //设置查询起始行            q.setFirstResult(index);            //查询返回的行数            q.setMaxResults(count);            List<Employee> list = q.list();            return list;        }catch (Exception e){            throw new RuntimeException(e);        }finally {            tx.commit();            session.close();        }    }    @Override    public void delete(Serializable id) {        Session session = null;        Transaction tx = null;        try {            session = HibernateUtils.getSession();            tx = session.beginTransaction();            //删除，先根据id查到对象，再删除对象            Object obj = session.get(Employee.class,id);            if (obj != null){                session.delete(obj);            }        }catch (Exception e){            throw new RuntimeException(e);        }finally {            tx.commit();            session.close();        }    }}

session获取工具类

package com.cx.utils;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.cfg.Configuration;/** * Created by cxspace on 16-7-19. */public class HibernateUtils {    private static SessionFactory sf;    static {        //加载主配置文件，并创建session对象        sf = new Configuration().configure().buildSessionFactory();    }    public static Session getSession(){        return sf.openSession();    }}

 

七.编写测试

package com.cx.test;import com.cx.crud.EmployeeDao;import com.cx.hello.Employee;/** * Created by cxspace on 16-7-23. */public class Test {    private EmployeeDao employeeDao = new EmployeeDao();    @org.junit.Test    public void testsave(){        Employee employee = new Employee();        employee.setEmpName("奥巴马");        employeeDao.save(employee);    }    public void testupdate(){        Employee employee =new Employee();        //更新必须设置主键        employee.setEmpId(24);        employee.setEmpName("new奥巴吗");        employeeDao.update(employee);    }    public void testfindById(){        System.out.println(employeeDao.findById(1));    }    public void testgetAll(){        System.out.println(employeeDao.getAll());    }    public void testgetByname(){        System.out.println(employeeDao.getAll("张三"));    }    public void testgetAllfenye(){        System.out.println(employeeDao.getAll(0,2));    }    public void delete(){        employeeDao.delete(27);    }}

附：数据库脚本

CREATE TABLE `employee` (  `id` int(11) NOT NULL AUTO_INCREMENT,  `empName` varchar(20) DEFAULT NULL,  `workDate` date DEFAULT NULL,  PRIMARY KEY (`id`)) ENGINE=InnoDB AUTO_INCREMENT=28 DEFAULT CHARSET=utf8

测试数据

1    张三    2016-07-182    jhon    2008-03-193    tim    2008-03-194    ooo    2013-04-105    cx    2008-03-196    eee22    2013-04-097    dedede    2009-04-308    abc    2009-04-309    eqwe    2009-04-3010    qwqwqw    2009-04-3011    ssdada    2009-04-3012    wqeqe    2009-04-2313    weqeqwewqe    2009-04-2314    abc    2009-04-3015    weqrq    2009-04-3016    cxspace    2009-04-2317    2132131    2009-04-3018    wtewtrt    2009-04-3019    eqrqrq    2009-04-3020    rwqrerq    2009-04-2321    aaasadad    1330-02-1922    小明    2016-07-1623    小华    2016-07-1628    奥巴马