hibernate课程 初探单表映射3-3 对象类型

本节简介：

1　　　　简介对象类型（重点是音视频blob类型）

2　　　　demo(对图片的写入数据库与读取)

1　　　　简介对象类型

映射类型　　　　　　　　java类型　　　　标准sql类型　　　　mysql类型　　　　oracle类型

binary　　　　　　　　　byte[]　　　　　　varchar　　　　　　blob　　　　　　blob

text(大文本类型)　　 　　java.lang.String　　clob　　　　　　　text　　　　　　  clob

clob（大文本类型）    　　java.sql.Clob　　　clob　　　　　　　text　　　　　　 clob

blob(二进制数据类型)  　　java.sql.Blob　　　 blob　　　　　　　blob　　　　　　blog　　　　　　　　用于存储图片，音频，视频等

2　　　　demo

hibernate.cft.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="connection.driver_class">com.mysql.jdbc.Driver</property>
     <property name="connection.url">jdbc:mysql://localhost:3306/bendi</property>
     <property name="connection.username">root</property>
     <property name="connection.password"></property>
     <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
     
     <property name="show_sql">true</property>
     <property name="format_sql">true</property>
     <property name="hbm2ddl.auto">update</property>
  
  <mapping resource = "Student.hbm.xml"/>     
    </session-factory>
</hibernate-configuration>

Student.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">
<!-- Generated 2017-12-20 0:42:12 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping>
    <class name="com.ddwei.student.Student" table="STUDENT">
        <id name="pid" type="int">
            <column name="PID" />
            <generator class="increment" />
        </id>
        <property name="name" type="java.lang.String">
            <column name="NAME" />
        </property>
        <property name="sex" type="java.lang.String">
            <column name="SEX" />
        </property>
        <property name="birthday" type="date">
<!--         <property name="birthday" type="time"> -->
<!--         <property name="birthday" type="timestamp"> -->
            <column name="BIRTHDAY" />
        </property>
        <property name="address" type="java.lang.String">
            <column name="ADDRESS" />
        </property>
        <property name="picture" type="java.sql.Blob">
            <column name="Picture" />
        </property>
    </class>
</hibernate-mapping>

Student.java

package com.ddwei.student;

import java.sql.Blob; import java.util.Date;

public class Student {

// java beans 的设计原则  /**   * 1 公有的类 2 共有不带参数构造方法 3 私有属性 4 属性setter/getter方法   */

private int pid;// 学号  private String name;// 姓名  private String sex;// 性别  private Date birthday;// 出生日期  private String address;// 家庭地址  private Blob picture;//相片

public Student() {

}

public Student(int pid, String name, String sex, Date birthday,    String address) {   // super();   this.pid = pid;   this.name = name;   this.sex = sex;   this.birthday = birthday;   this.address = address;  }

@Override  public String toString() {   return "Student [pid=" + pid + ", name=" + name + ", sex=" + sex     + ", birthday=" + birthday + ", address=" + address + "]";  }

public int getPid() {   return pid;  }

public void setPid(int pid) {   this.pid = pid;  }

public Date getBirthday() {   return birthday;  }

public void setBirthday(Date birthday) {   this.birthday = birthday;  }

public String getAddress() {   return address;  }

public void setAddress(String address) {   this.address = address;  }

public String getName() {   return name;  }

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

public String getSex() {   return sex;  }

public void setSex(String sex) {   this.sex = sex;  }

public Blob getPicture() {   return picture;  }

public void setPicture(Blob picture) {   this.picture = picture;  }

}

StudentTest.java

package hibernate_001;

import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.sql.Blob; import java.sql.SQLException; import java.util.Date;

import org.hibernate.Hibernate; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.Transaction; import org.hibernate.cfg.Configuration; import org.hibernate.service.ServiceRegistry; import org.hibernate.service.ServiceRegistryBuilder; import org.junit.After; import org.junit.Before; import org.junit.Test;

import com.ddwei.student.Student;

public class StudentTest {    private SessionFactory sessionFactory;  private Session session;  private Transaction trasaction;    @Test  public void testSaveStudent(){ //  Student student =new Student(1,"周恩来","男",new Date(),"绍兴");//创建学生对象   Student student = new Student(); //  student.setPid(100);   student.setName("秦始皇");   student.setSex("男");   student.setBirthday(new Date());   student.setAddress("阿房宫");   session.save(student);//会话保存学生对象进入数据库  }              /**   * 图片(二进制)写入数据库   * @throws IOException   */  @Test  public void testWriteBlob() throws IOException{   Student student =new Student(1,"周恩来","男",new Date(),"绍兴");//创建学生对象      //1  先获取照片文件：  File.separator 是文件分隔符   File file = new File("g:"+File.separator+"tupian"+File.separator+"psb.jpg");   //2  获得文杰输入流（字节流）   InputStream input = new FileInputStream(file);   //3  创建一个blob对象  input.available()输入流的长度   Blob picture = Hibernate.getLobCreator(session).createBlob(input, input.available());   //4  设置照片属性   student.setPicture(picture);      //5  保存学生   session.save(student);     }        /**   * 图片(二进制)读取   * @throws SQLException   * @throws IOException   */  @Test  public void testReadBlob() throws SQLException, IOException{   //1  加载学生对象   Student student = (Student) session.get(Student.class, 1); //  System.out.println(student.getName());   //2  获得Blob对象   Blob picture = student.getPicture();   //3  获得输入流   InputStream input = picture.getBinaryStream();   //4  获得文件   File file = new File("d:"+File.separator+"a.jpg");   //5  获得输出流   OutputStream output = new FileOutputStream(file);   //6  创建缓冲区   byte[] buff = new byte[input.available()];      //7  把输入流读取到缓冲区   input.read(buff);   //8  输出流写入缓冲区的内容   output.write(buff);      //9  关闭输入流和输出流   input.close();   output.close();  }                                  @Before  public void init(){   //1  创建配置对象   Configuration config = new Configuration().configure();   //2  创建服务对象   ServiceRegistry serviceRe = new ServiceRegistryBuilder().applySettings(config.getProperties()).buildServiceRegistry();      //3  创建会话工厂   sessionFactory = config.buildSessionFactory(serviceRe);      //4  打开会话   session = sessionFactory.openSession();   //5  创建事务   trasaction = session.beginTransaction();  }      @After  public void destroy(){   trasaction.commit();   session.close();   sessionFactory.close();  }

}