（六）Hibernate 映射类型

所有项目导入对应的hibernate的jar包、mysql的jar包和添加每次都需要用到的HibernateUtil.java

第一节：基本类型映射

例子：

hibernate.cfg.xml

 1 <?xml version='1.0' encoding='utf-8'?>
 2 <!DOCTYPE hibernate-configuration PUBLIC
 3         "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
 4         "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
 5 
 6 <hibernate-configuration>
 7 
 8     <session-factory>
 9 
10         <!--数据库连接设置 -->
11         <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
12         <property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>
13         <property name="connection.username">root</property>
14         <property name="connection.password">123456</property>
15 
16        
17         <!-- 方言 -->
18         <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
19     
20         <!-- 控制台显示SQL -->
21         <property name="show_sql">true</property>
22 
23         <!-- 自动更新表结构 -->
24         <property name="hbm2ddl.auto">update</property>
25         
26           <mapping resource="com/wishwzp/model/Student.hbm.xml"/>
27           
28           <mapping resource="com/wishwzp/model/Book.hbm.xml"/>
29 
30     </session-factory>
31 
32 </hibernate-configuration>

Book.java

 1 package com.wishwzp.model;
 2 
 3 import java.sql.Blob;
 4 import java.util.Date;
 5 
 6 public class Book {
 7 
 8     private int id;
 9     private String bookName; // 图书名称
10     private float price; // 图书价格
11     private boolean specialPrice; // 是否是特价
12     private Date publishDate; // 发布日期
13     private String author; // 作者
14     private String introduction; // 简介
15     private Blob bookPic; // 图书图片
16     
17     public int getId() {
18         return id;
19     }
20     public void setId(int id) {
21         this.id = id;
22     }
23     public String getBookName() {
24         return bookName;
25     }
26     public void setBookName(String bookName) {
27         this.bookName = bookName;
28     }
29     public float getPrice() {
30         return price;
31     }
32     public void setPrice(float price) {
33         this.price = price;
34     }
35     public boolean isSpecialPrice() {
36         return specialPrice;
37     }
38     public void setSpecialPrice(boolean specialPrice) {
39         this.specialPrice = specialPrice;
40     }
41     public Date getPublishDate() {
42         return publishDate;
43     }
44     public void setPublishDate(Date publishDate) {
45         this.publishDate = publishDate;
46     }
47     public String getAuthor() {
48         return author;
49     }
50     public void setAuthor(String author) {
51         this.author = author;
52     }
53     public String getIntroduction() {
54         return introduction;
55     }
56     public void setIntroduction(String introduction) {
57         this.introduction = introduction;
58     }
59     public Blob getBookPic() {
60         return bookPic;
61     }
62     public void setBookPic(Blob bookPic) {
63         this.bookPic = bookPic;
64     }
65     
66     
67     
68 }

Book.hbm.xml

 1 <?xml version="1.0"?>
 2 <!DOCTYPE hibernate-mapping PUBLIC
 3         "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
 4         "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
 5 
 6 <hibernate-mapping package="com.wishwzp.model">
 7 
 8     <class name="Book" table="t_book">
 9         <id name="id" column="bookId">
10             <generator class="native"></generator>
11         </id>
12         
13         <property name="bookName" column="bookName" length="40"></property>
14         <property name="price" column="price" type="float"></property>
15         <property name="specialPrice" column="specialPrice" type="boolean"></property>
16         <property name="publishDate" column="publishDate" type="date"></property>
17         <property name="author" column="author" length="20"></property>
18         <property name="introduction" column="introduction" type="text"></property>
19         <property name="bookPic" column="bookPic" type="blob"></property>
20     </class>
21 
22 </hibernate-mapping>

BookTest.java

 1 package com.wishwzp.service;
 2 
 3 import java.io.FileInputStream;
 4 import java.io.InputStream;
 5 import java.sql.Blob;
 6 import java.text.SimpleDateFormat;
 7 
 8 import org.hibernate.LobHelper;
 9 import org.hibernate.Session;
10 import org.hibernate.SessionFactory;
11 
12 import com.wishwzp.model.Book;
13 import com.wishwzp.util.HibernateUtil;
14 
15 public class BookTest {
16     
17     public static void main(String[] args) throws Exception{
18         SessionFactory sessionFactory=HibernateUtil.getSessionFactory();
19         Session session=sessionFactory.openSession(); // 生成一个session
20         session.beginTransaction(); // 开启事务
21         
22         Book book=new Book();
23         book.setBookName("java编程思想");
24         book.setPrice(100);
25         book.setSpecialPrice(true);
26         book.setPublishDate(new SimpleDateFormat("yyyy-MM-dd").parse("2013-1-1"));
27         book.setAuthor("埃克尔");
28         book.setIntroduction("简介...");
29         
30         //
31         LobHelper lobHelper=session.getLobHelper();
32         InputStream in=new FileInputStream("c://java编程思想.jpg");
33         Blob bookPic=lobHelper.createBlob(in, in.available());
34         book.setBookPic(bookPic);
35        
36         session.save(book);
37         
38         session.getTransaction().commit(); // 提交事务
39         session.close(); // 关闭session
40      
41     }
42 }

HibernateUtil.java

 1 package com.wishwzp.util;
 2 
 3 import org.hibernate.SessionFactory;
 4 import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
 5 import org.hibernate.cfg.Configuration;
 6 import org.hibernate.service.ServiceRegistry;
 7 
 8 /**
 9  * 
10  * hibernate封装
11  * @author wishwzp
12  *
13  */
14 public class HibernateUtil {
15     
16     private static final SessionFactory sessionFactory=buildSessionFactory();
17 
18     /**
19      * 绑定SessionFactory
20      * @return
21      */
22     private static SessionFactory buildSessionFactory(){
23         // 实例化配置文件
24         Configuration configuration=new Configuration().configure(); 
25         // 实例化服务登记
26         ServiceRegistry serviceRegistry=new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();
27         //获取Session工厂
28         return configuration.buildSessionFactory(serviceRegistry);
29     }
30     
31     public static SessionFactory getSessionFactory(){
32         return sessionFactory;
33     }
34 }

第二节：集合类型映射

hibernate.cfg.xml

 1 <?xml version='1.0' encoding='utf-8'?>
 2 <!DOCTYPE hibernate-configuration PUBLIC
 3         "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
 4         "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
 5 
 6 <hibernate-configuration>
 7 
 8     <session-factory>
 9 
10         <!--数据库连接设置 -->
11         <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
12         <property name="connection.url">jdbc:mysql://localhost:3306/hibernate</property>
13         <property name="connection.username">root</property>
14         <property name="connection.password">123456</property>
15 
16        
17         <!-- 方言 -->
18         <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
19     
20         <!-- 控制台显示SQL -->
21         <property name="show_sql">true</property>
22 
23         <!-- 自动更新表结构 -->
24         <property name="hbm2ddl.auto">update</property>
25         
26           <mapping resource="com/wishwzp/model/Student.hbm.xml"/>
27           <mapping resource="com/wishwzp/model/Student2.hbm.xml"/>
28           <mapping resource="com/wishwzp/model/Student3.hbm.xml"/>
29           <mapping resource="com/wishwzp/model/Student4.hbm.xml"/>
30 
31     </session-factory>
32 
33 </hibernate-configuration>

1，Set 无序元素不可重复

Student.java

 1 package com.wishwzp.model;
 2 
 3 import java.util.Set;
 4 
 5 public class Student {
 6 
 7     private long id;
 8     private String name;
 9     private Set<String> images;
10     
11     public long getId() {
12         return id;
13     }
14     public void setId(long id) {
15         this.id = id;
16     }
17     public String getName() {
18         return name;
19     }
20     public void setName(String name) {
21         this.name = name;
22     }
23     public Set<String> getImages() {
24         return images;
25     }
26     public void setImages(Set<String> images) {
27         this.images = images;
28     }
29     
30     
31     
32     
33 }

Student.hbm.xml

 1 <?xml version="1.0"?>
 2 <!DOCTYPE hibernate-mapping PUBLIC
 3         "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
 4         "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
 5 
 6 <hibernate-mapping package="com.wishwzp.model">
 7 
 8     <class name="Student" table="t_student">
 9         <id name="id" column="stuId">
10             <generator class="native"></generator>
11         </id>
12         
13         <property name="name" column="stuName"></property>
14         
15         <set name="images" table="t_image">
16             <key column="studentId"></key>
17             <element column="imageName" type="string"></element>
18         </set>
19     </class>
20 
21 </hibernate-mapping>

2，List 有序元素可重复

Studnet2.java

 1 package com.wishwzp.model;
 2 
 3 import java.util.List;
 4 
 5 public class Student2 {
 6 
 7     private long id;
 8     private String name;
 9     private List<String> images;
10     
11     public long getId() {
12         return id;
13     }
14     public void setId(long id) {
15         this.id = id;
16     }
17     public String getName() {
18         return name;
19     }
20     public void setName(String name) {
21         this.name = name;
22     }
23     public List<String> getImages() {
24         return images;
25     }
26     public void setImages(List<String> images) {
27         this.images = images;
28     }
29     
30 }

Student2.hbm.xml

 1 <?xml version="1.0"?>
 2 <!DOCTYPE hibernate-mapping PUBLIC
 3         "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
 4         "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
 5 
 6 <hibernate-mapping package="com.wishwzp.model">
 7 
 8     <class name="Student2" table="t_student">
 9         <id name="id" column="stuId">
10             <generator class="native"></generator>
11         </id>
12         
13         <property name="name" column="stuName"></property>
14         
15         <list name="images" table="t_image2">
16             <key column="studentId"></key>
17             <list-index column="imageIndex"></list-index>
18             <element column="imageName" type="string"></element>
19         </list>
20     </class>
21 
22 </hibernate-mapping>

3，Bag 无序元素可重复

Student3.java

 1 package com.wishwzp.model;
 2 
 3 import java.util.List;
 4 
 5 public class Student3 {
 6 
 7     private long id;
 8     private String name;
 9     private List<String> images;
10     
11     public long getId() {
12         return id;
13     }
14     public void setId(long id) {
15         this.id = id;
16     }
17     public String getName() {
18         return name;
19     }
20     public void setName(String name) {
21         this.name = name;
22     }
23     public List<String> getImages() {
24         return images;
25     }
26     public void setImages(List<String> images) {
27         this.images = images;
28     }
29     
30 }

Student3.hbm.xml

 1 <?xml version="1.0"?>
 2 <!DOCTYPE hibernate-mapping PUBLIC
 3         "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
 4         "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
 5 
 6 <hibernate-mapping package="com.wishwzp.model">
 7 
 8     <class name="Student3" table="t_student">
 9         <id name="id" column="stuId">
10             <generator class="native"></generator>
11         </id>
12         
13         <property name="name" column="stuName"></property>
14         
15         <idbag name="images" table="t_image3">
16             <collection-id type="long" column="imageId">
17                 <generator class="increment"></generator>
18             </collection-id>
19             <key column="studentId"></key>
20             <element column="imageName" type="string"></element>
21         </idbag>
22         
23     
24     </class>
25 
26 </hibernate-mapping>

4，Map 键值对

Student4.java

 1 package com.wishwzp.model;
 2 
 3 import java.util.Map;
 4 
 5 public class Student4 {
 6 
 7     private long id;
 8     private String name;
 9     private Map<String,String> images;
10     
11     public long getId() {
12         return id;
13     }
14     public void setId(long id) {
15         this.id = id;
16     }
17     public String getName() {
18         return name;
19     }
20     public void setName(String name) {
21         this.name = name;
22     }
23     public Map<String, String> getImages() {
24         return images;
25     }
26     public void setImages(Map<String, String> images) {
27         this.images = images;
28     }
29     
30 }

Student4.hbm.xml

 1 <?xml version="1.0"?>
 2 <!DOCTYPE hibernate-mapping PUBLIC
 3         "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
 4         "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
 5 
 6 <hibernate-mapping package="com.wishwzp.model">
 7 
 8     <class name="Student4" table="t_student">
 9         <id name="id" column="stuId">
10             <generator class="native"></generator>
11         </id>
12         
13         <property name="name" column="stuName"></property>
14         
15         <map name="images" table="t_image4">
16             <key column="studentId"></key>
17             <map-key column="imageKey" type="string"></map-key>
18             <element column="imageName" type="string"></element>
19         </map>
20         
21     
22     </class>
23 
24 </hibernate-mapping>

上面4种情况的总测试类：

StudentTest.java

  1 package com.wishwzp.service;
  2 
  3 import java.util.ArrayList;
  4 import java.util.HashMap;
  5 import java.util.HashSet;
  6 import java.util.Iterator;
  7 import java.util.List;
  8 import java.util.Map;
  9 import java.util.Set;
 10 
 11 import org.hibernate.Session;
 12 import org.hibernate.SessionFactory;
 13 import org.junit.After;
 14 import org.junit.Before;
 15 import org.junit.Test;
 16 
 17 import com.wishwzp.model.Student;
 18 import com.wishwzp.model.Student2;
 19 import com.wishwzp.model.Student3;
 20 import com.wishwzp.model.Student4;
 21 import com.wishwzp.util.HibernateUtil;
 22 
 23 public class StudentTest {
 24 
 25     private SessionFactory sessionFactory=HibernateUtil.getSessionFactory();
 26     private Session session;
 27     
 28     @Before
 29     public void setUp() throws Exception {
 30         session=sessionFactory.openSession(); // 生成一个session
 31         session.beginTransaction(); // 开启事务
 32     }
 33 
 34     @After
 35     public void tearDown() throws Exception {
 36          session.getTransaction().commit(); // 提交事务
 37          session.close(); // 关闭session
 38     }
 39 
 40     //1、Set 无序元素不可重复
 41     @Test
 42     public void testSetSave(){
 43         Set<String> imageSet=new HashSet<String>();
 44         imageSet.add("image1.png");
 45         imageSet.add("image2.png");
 46         imageSet.add("image3.png");
 47         imageSet.add("image3.png");//这里有重复，但在数据库里面只有一个image3.png并且是无序的。。。所以set元素不可重复
 48         
 49         Student s1=new Student();
 50         s1.setImages(imageSet);
 51         session.save(s1);
 52     }
 53     
 54     //打印出来Student表id为1的images表的所有image信息
 55     @Test
 56     public void testSetFetch(){
 57         Student student=(Student)session.get(Student.class, Long.valueOf(1));
 58         Iterator it=student.getImages().iterator();
 59         while(it.hasNext()){
 60             System.out.println(it.next());
 61         }
 62     }
 63     
 64     //2、List 有序元素可重复
 65     @Test
 66     public void testListSave(){
 67         List<String> imageList=new ArrayList<String>();
 68         imageList.add("image1.png");
 69         imageList.add("image2.png");
 70         imageList.add("image3.png");
 71         imageList.add("image3.png");//这里有重复，数据库里面也可以有两个image3.png并且是有序的。。。所以list元素可重复
 72         
 73         Student2 s2=new Student2();
 74         s2.setImages(imageList);
 75         session.save(s2);
 76     }
 77     
 78     //打印出来Student表id为1的images表的所有image信息
 79     @Test
 80     public void testListFetch(){
 81         Student2 student2=(Student2)session.get(Student2.class, Long.valueOf(2));
 82         Iterator it=student2.getImages().iterator();
 83         while(it.hasNext()){
 84             System.out.println(it.next());
 85         }
 86     }
 87     
 88     //3、Bag 无序元素可重复
 89     @Test
 90     public void testBagSave(){
 91         List<String> imageList=new ArrayList<String>();
 92         imageList.add("image1.png");
 93         imageList.add("image2.png");
 94         imageList.add("image3.png");
 95         imageList.add("image3.png");//这里有重复，数据库里面也有两个image3.png而且是无序的。。。所以Bag 无序元素可重复
 96         
 97         Student3 s3=new Student3();
 98         s3.setImages(imageList);
 99         session.save(s3);
100     }
101     
102     
103     @Test
104     public void testBagFetch(){
105         Student3 student3=(Student3)session.get(Student3.class, Long.valueOf(3));
106         Iterator it=student3.getImages().iterator();
107         while(it.hasNext()){
108             System.out.println(it.next());
109         }
110     }
111     
112     //4、Map 键值对
113     @Test
114     public void testMapSave(){
115         Map<String,String> imageMap=new HashMap<String,String>();
116         imageMap.put("i1", "image1.png");
117         imageMap.put("i2", "image2.png");
118         imageMap.put("i3", "image3.png");
119         imageMap.put("i4", "image4.png");//这里都是键值对的
120         
121         Student4 s4=new Student4();
122         s4.setImages(imageMap);
123         session.save(s4);
124     }
125     
126     
127     @Test
128     public void testMapFetch(){
129         Student4 student4=(Student4)session.get(Student4.class, Long.valueOf(4));
130         Map<String,String> imageMap=student4.getImages();
131         Set keys=imageMap.keySet();
132         Iterator it=keys.iterator();
133         while(it.hasNext()){
134             String key=(String)it.next();
135             System.out.println(key+":"+imageMap.get(key));
136         }
137     }
138 
139 }

结果显示：

1，Set 无序元素不可重复

testSetSave()方法：

testSetFech()方法：

2，List 有序元素可重复

testListSave()方法：

testListFech()方法：

3，Bag 无序元素可重复

testBagSave()方法:

testBagFech()方法:

4，Map 键值对

testMapSave()方法：

testMapFech()方法：

所有表之间的关系：

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原文地址：https://www.cnblogs.com/wishwzp/p/5481270.html