[Hibernate单表操作] 对象类型

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一 对象类型

 

 

二 将图片写入数据库

1、Students

import java.sql.Blob;

import java.util.Date;

//学生类

public class Students {

        /*

         * JavaBeans的四点原则

         * 1.必须是公有的类

         * 2.提供公有的不带参数的默认的构造方法

         * 3.属性私有

         * 4.属性setter/getter封装

         */

        private int sid; // 学号

        private String sname; // 姓名

        private String gender; // 性别

        private Date birthday; // 出生日期

        private String address; // 地址

        private Blob picture;//照片

        

        public Blob getPicture() {

                return picture;

        }

 

        public void setPicture(Blob picture) {

                this.picture = picture;

        }

 

        public Students() {

        }

 

        public Students(int sid, String sname, String gender, Date birthday,

                        String address) {

                // super();

                this.sid = sid;

                this.sname = sname;

                this.gender = gender;

                this.birthday = birthday;

                this.address = address;

        }

 

        public int getSid() {

                return sid;

        }

 

        public void setSid(int sid) {

                this.sid = sid;

        }

 

        public String getSname() {

                return sname;

        }

 

        public void setSname(String sname) {

                this.sname = sname;

        }

 

        public String getGender() {

                return gender;

        }

 

        public void setGender(String gender) {

                this.gender = gender;

        }

 

        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;

        }

 

        @Override

        public String toString() {

                return "Students [sid=" + sid + ", sname=" + sname + ", gender="

                                + gender + ", birthday=" + birthday + ", address=" + address

                                + "]";

        }

 

}

2、hibernate.cfg.xml配置

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="Students" table="STUDENTS">

        <id name="sid" type="int">

            <column name="SID" />

            <generator class="native" />

           

        id>

        <property name="sname" type="java.lang.String">

            <column name="SNAME" />

        property>

        <property name="gender" type="java.lang.String">

            <column name="GENDER" />

        property>

        <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>

3、测试方法

        @Test

        public void testWriteBlog() throws Exception{

                Students s= new Students(1,"张三丰","男",new Date(),"武当山");

                //先获得照片文件

                File f = new File("E:"+File.separator+"1.png");

                //获得照片文件的输入流

                InputStream input = new FileInputStream(f);

                //创建一个Blob对象

                Blob image = Hibernate.getLobCreator(session).createBlob(input, input.available());

                //设置照片属性

                s.setPicture(image);

            session.save(s);

        }

4、测试结果

 

 

三 将图片从数据库读出

1、测试方法

        @Test

        public void testReadBlog() throws Exception{

                Students s= (Students)session.get(Students.class, 1);

                //获得Blob对象

                Blob image = s.getPicture();

                //获得照片的输入流

                InputStream input = image.getBinaryStream();

                //创建文件

                File f = new File("E:"+File.separator+"2.png");

                //获得输出流

                OutputStream output = new FileOutputStream(f);

                //创建缓冲区

                byte[] buff = new byte[input.available()];

                input.read(buff);

                output.write(buff);

                input.close();

                output.close();

        }

2、测试结果

 

 

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