Hibernate-关系映射

一、一对一双向外键关联【Husband-Wife】

Husband.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.Entity;
 4 import javax.persistence.GeneratedValue;
 5 import javax.persistence.Id;
 6 import javax.persistence.JoinColumn;
 7 import javax.persistence.OneToOne;
 8 
 9 @Entity
10 public class Husband
11 {
12     private int id;
13     private String name;
14     private Wife wife;
15 
16     @OneToOne
17     @JoinColumn(name="wifeId")
18     public Wife getWife()
19     {
20         return wife;
21     }
22 
23     public void setWife(Wife wife)
24     {
25         this.wife = wife;
26     }
27 
28     @Id
29     @GeneratedValue
30     public int getId()
31     {
32         return id;
33     }
34 
35     public void setId(int id)
36     {
37         this.id = id;
38     }
39 
40     public String getName()
41     {
42         return name;
43     }
44 
45     public void setName(String name)
46     {
47         this.name = name;
48     }
49 
50 }

Wife.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.CascadeType;
 4 import javax.persistence.Entity;
 5 import javax.persistence.GeneratedValue;
 6 import javax.persistence.Id;
 7 import javax.persistence.JoinColumn;
 8 import javax.persistence.OneToOne;
 9 
10 @Entity
11 public class Wife
12 {
13     private int id;
14     private String name;
15     private Husband husband=new Husband();
16 
17     @OneToOne(mappedBy="wife",cascade=CascadeType.ALL)    
18     public Husband getHusband()
19     {
20         return husband;
21     }
22 
23     public void setHusband(Husband husband)
24     {
25         this.husband = husband;
26     }
27 
28     @Id
29     @GeneratedValue
30     public int getId()
31     {
32         return id;
33     }
34 
35     public void setId(int id)
36     {
37         this.id = id;
38     }
39 
40     public String getName()
41     {
42         return name;
43     }
44 
45     public void setName(String name)
46     {
47         this.name = name;
48     }
49 }

生成的SQL语句如下：

View Code

 1 16:06:06,578  INFO SchemaExport:226 - Running hbm2ddl schema export
 2 16:06:06,578 DEBUG SchemaExport:242 - import file not found: /import.sql
 3 16:06:06,578  INFO SchemaExport:251 - exporting generated schema to database
 4 16:06:06,765 DEBUG SchemaExport:377 - 
 5     drop table Husband cascade constraints
 6 16:06:06,906 DEBUG SchemaExport:377 - 
 7     drop table Wife cascade constraints
 8 16:06:06,968 DEBUG SchemaExport:377 - 
 9     drop sequence hibernate_sequence
10 16:06:06,984 DEBUG SchemaExport:377 - 
11     create table Husband (
12         id number(10,0) not null,
13         name varchar2(255 char),
14         wifeId number(10,0),
15         primary key (id)
16     )
17 16:06:07,062 DEBUG SchemaExport:377 - 
18     create table Wife (
19         id number(10,0) not null,
20         name varchar2(255 char),
21         primary key (id)
22     )
23 16:06:07,109 DEBUG SchemaExport:377 - 
24     alter table Husband 
25         add constraint FKAEEA401BD5255EDF 
26         foreign key (wifeId) 
27         references Wife
28 16:06:07,109 DEBUG SchemaExport:377 - 
29     create sequence hibernate_sequence
30 16:06:07,109  INFO SchemaExport:268 - schema export complete

生成的表结构如下：

二、一对多单向关联【UserGroup-User】

User.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.Entity;
 4 import javax.persistence.GeneratedValue;
 5 import javax.persistence.Id;
 6 import javax.persistence.Table;
 7 
 8 @Entity
 9 @Table(name = "t_User")
10 public class User
11 {
12     private int id;
13     private String name;
14 
15     public User()
16     {
17 
18     }
19 
20     public User(String name)
21     {
22         super();
23         this.name = name;
24     }
25 
26     @Id
27     @GeneratedValue
28     public int getId()
29     {
30         return id;
31     }
32 
33     public void setId(int id)
34     {
35         this.id = id;
36     }
37 
38     public String getName()
39     {
40         return name;
41     }
42 
43     public void setName(String name)
44     {
45         this.name = name;
46     }
47 
48 }

UserGroup.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import java.util.HashSet;
 4 import java.util.Set;
 5 
 6 import javax.persistence.CascadeType;
 7 import javax.persistence.Entity;
 8 import javax.persistence.GeneratedValue;
 9 import javax.persistence.Id;
10 import javax.persistence.JoinColumn;
11 import javax.persistence.OneToMany;
12 
13 @Entity
14 public class UserGroup
15 {
16     private int id;
17     private String name;
18     private Set<User> moreUsers=new HashSet<User>();
19     
20     @OneToMany(cascade=CascadeType.ALL)    
21     @JoinColumn(name="groupId") //向多的一方(User)加外键，必须要指定外键的名称，否则会出现中间表
22     public Set<User> getMoreUsers()
23     {
24         return moreUsers;
25     }
26 
27     public void setMoreUsers(Set<User> moreUsers)
28     {
29         this.moreUsers = moreUsers;
30     }
31 
32     @Id
33     @GeneratedValue
34     public int getId()
35     {
36         return id;
37     }
38 
39     public void setId(int id)
40     {
41         this.id = id;
42     }
43 
44     public String getName()
45     {
46         return name;
47     }
48 
49     public void setName(String name)
50     {
51         this.name = name;
52     }
53 
54 }

生成的SQL语句如下：

View Code

 1 16:17:23,625  INFO SchemaExport:226 - Running hbm2ddl schema export
 2 16:17:23,625 DEBUG SchemaExport:242 - import file not found: /import.sql
 3 16:17:23,625  INFO SchemaExport:251 - exporting generated schema to database
 4 16:17:23,781 DEBUG SchemaExport:377 - 
 5     drop table UserGroup cascade constraints
 6 16:17:23,812 DEBUG SchemaExport:377 - 
 7     drop table t_User cascade constraints
 8 16:17:23,828 DEBUG SchemaExport:377 - 
 9     drop sequence hibernate_sequence
10 16:17:23,828 DEBUG SchemaExport:377 - 
11     create table UserGroup (
12         id number(10,0) not null,
13         name varchar2(255 char),
14         primary key (id)
15     )
16 16:17:23,906 DEBUG SchemaExport:377 - 
17     create table t_User (
18         id number(10,0) not null,
19         name varchar2(255 char),
20         groupId number(10,0),
21         primary key (id)
22     )
23 16:17:23,968 DEBUG SchemaExport:377 - 
24     alter table t_User 
25         add constraint FKCB5540D68698CAAC 
26         foreign key (groupId) 
27         references UserGroup
28 16:17:23,968 DEBUG SchemaExport:377 - 
29     create sequence hibernate_sequence
30 16:17:23,968  INFO SchemaExport:268 - schema export complete

生成的表结构如下：

插入数据：

View Code

 1 @Test
 2     public void testUserGroupAdd()
 3     {
 4         Transaction transaction = null;
 5         try
 6         {
 7             Session session = sessionFactory.getCurrentSession();
 8             transaction = session.beginTransaction();
 9             UserGroup group=new UserGroup();
10             group.setName("组1");
11             User u1=new User("张三");            
12             User u2=new User("李四");
13             User u3=new User("王武");
14             group.getMoreUsers().add(u1);
15             group.getMoreUsers().add(u2);
16             group.getMoreUsers().add(u3);
17             session.save(group);
18 
19             transaction.commit();
20         }
21         catch (Exception e)
22         {
23             e.printStackTrace();
24             transaction.rollback();
25         }
26     }

三、多对一单向关联【User-UserGroup】

User.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.CascadeType;
 4 import javax.persistence.Entity;
 5 import javax.persistence.GeneratedValue;
 6 import javax.persistence.Id;
 7 import javax.persistence.JoinColumn;
 8 import javax.persistence.ManyToOne;
 9 import javax.persistence.Table;
10 
11 @Entity
12 @Table(name = "t_User")
13 public class User
14 {
15     private int id;
16     private String name;
17     private UserGroup userGroup=new UserGroup();
18 
19     public User()
20     {
21 
22     }
23 
24     public User(String name)
25     {
26         super();
27         this.name = name;
28     }
29 
30     @Id
31     @GeneratedValue
32     public int getId()
33     {
34         return id;
35     }
36 
37     public void setId(int id)
38     {
39         this.id = id;
40     }
41 
42     @ManyToOne(cascade=CascadeType.ALL)
43     @JoinColumn(name = "userGroupId")
44     public UserGroup getUserGroup()
45     {
46         return userGroup;
47     }
48 
49     public void setUserGroup(UserGroup userGroup)
50     {
51         this.userGroup = userGroup;
52     }
53 
54     public String getName()
55     {
56         return name;
57     }
58 
59     public void setName(String name)
60     {
61         this.name = name;
62     }
63 
64 }

UserGroup.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.Entity;
 4 import javax.persistence.GeneratedValue;
 5 import javax.persistence.Id;
 6 
 7 @Entity
 8 public class UserGroup
 9 {
10     private int id;
11     private String name;
12 
13     @Id
14     @GeneratedValue
15     public int getId()
16     {
17         return id;
18     }
19 
20     public void setId(int id)
21     {
22         this.id = id;
23     }
24 
25     public String getName()
26     {
27         return name;
28     }
29 
30     public void setName(String name)
31     {
32         this.name = name;
33     }
34 
35 }

表结构与生成的SQL语句同二。

插入数据：

View Code

 1 @Test
 2     public void testUserAdd()
 3     {
 4         Transaction transaction = null;
 5         try
 6         {
 7             Session session = sessionFactory.getCurrentSession();
 8             transaction = session.beginTransaction();
 9             User u1 = new User("张三");
10             u1.getUserGroup().setName("组1");
11             User u2 = new User("李四");
12             u2.getUserGroup().setName("组1");
13             User u3 = new User("王武");
14             u3.getUserGroup().setName("组1");
15 
16             session.save(u1);
17             session.save(u2);
18             session.save(u3);
19 
20             transaction.commit();
21         }
22         catch (Exception e)
23         {
24             e.printStackTrace();
25             transaction.rollback();
26         }
27     }

四、一对多，多对一双向关联【User-UserGroup】

User.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.CascadeType;
 4 import javax.persistence.Entity;
 5 import javax.persistence.GeneratedValue;
 6 import javax.persistence.Id;
 7 import javax.persistence.JoinColumn;
 8 import javax.persistence.ManyToOne;
 9 import javax.persistence.Table;
10 
11 @Entity
12 @Table(name = "t_User")
13 public class User
14 {
15     private int id;
16     private String name;
17     private UserGroup userGroup;
18 
19     public User()
20     {
21 
22     }
23 
24     public User(String name)
25     {
26         super();
27         this.name = name;
28     }
29 
30     @Id
31     @GeneratedValue
32     public int getId()
33     {
34         return id;
35     }
36 
37     public void setId(int id)
38     {
39         this.id = id;
40     }
41 
42     @ManyToOne
43     @JoinColumn(name = "userGroupId")
44     public UserGroup getUserGroup()
45     {
46         return userGroup;
47     }
48 
49     public void setUserGroup(UserGroup userGroup)
50     {
51         this.userGroup = userGroup;
52     }
53 
54     public String getName()
55     {
56         return name;
57     }
58 
59     public void setName(String name)
60     {
61         this.name = name;
62     }
63 
64 }

UserGroup.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import java.util.HashSet;
 4 import java.util.Set;
 5 
 6 import javax.persistence.CascadeType;
 7 import javax.persistence.Entity;
 8 import javax.persistence.GeneratedValue;
 9 import javax.persistence.Id;
10 import javax.persistence.JoinColumn;
11 import javax.persistence.OneToMany;
12 
13 @Entity
14 public class UserGroup
15 {
16     private int id;
17     private String name;
18     private Set<User> moreUsers=new HashSet<User>();
19     
20     @OneToMany(mappedBy="userGroup",cascade=CascadeType.ALL)    
21     public Set<User> getMoreUsers()
22     {
23         return moreUsers;
24     }
25 
26     public void setMoreUsers(Set<User> moreUsers)
27     {
28         this.moreUsers = moreUsers;
29     }
30 
31     @Id
32     @GeneratedValue
33     public int getId()
34     {
35         return id;
36     }
37 
38     public void setId(int id)
39     {
40         this.id = id;
41     }
42 
43     public String getName()
44     {
45         return name;
46     }
47 
48     public void setName(String name)
49     {
50         this.name = name;
51     }
52 
53 }

表结构与生成的SQL语句同二。

插入数据：

View Code

 1 @Test
 2     public void testUserGroupAdd()
 3     {
 4         Transaction transaction = null;
 5         try
 6         {
 7             Session session = sessionFactory.getCurrentSession();
 8             transaction = session.beginTransaction();
 9             UserGroup group=new UserGroup();
10             group.setName("组1");
11             User u1=new User("张三");
12             u1.setUserGroup(group);
13             User u2=new User("李四");
14             u2.setUserGroup(group);
15             User u3=new User("王武");
16             u3.setUserGroup(group);
17             group.getMoreUsers().add(u1);
18             group.getMoreUsers().add(u2);
19             group.getMoreUsers().add(u3);
20             session.save(group);
21 
22             transaction.commit();
23         }
24         catch (Exception e)
25         {
26             e.printStackTrace();
27             transaction.rollback();
28         }
29     }

五、多对多双向关联【Student-Teacher】

Student.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import java.util.Set;
 4 
 5 import javax.persistence.Entity;
 6 import javax.persistence.GeneratedValue;
 7 import javax.persistence.Id;
 8 import javax.persistence.ManyToMany;
 9 
10 @Entity
11 public class Student
12 {
13     private int id;
14     private String name;
15     private Set<Teacher> allTeacher;
16 
17     public Student()
18     {
19 
20     }
21 
22     public Student(String name)
23     {
24         super();
25         this.name = name;
26     }
27 
28     @ManyToMany(mappedBy = "allStudent")
29     public Set<Teacher> getAllTeacher()
30     {
31         return allTeacher;
32     }
33 
34     public void setAllTeacher(Set<Teacher> allTeacher)
35     {
36         this.allTeacher = allTeacher;
37     }
38 
39     @Id
40     @GeneratedValue
41     public int getId()
42     {
43         return id;
44     }
45 
46     public void setId(int id)
47     {
48         this.id = id;
49     }
50 
51     public String getName()
52     {
53         return name;
54     }
55 
56     public void setName(String name)
57     {
58         this.name = name;
59     }
60 
61 }

Teacher.java

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import java.util.HashSet;
 4 import java.util.Set;
 5 
 6 import javax.persistence.CascadeType;
 7 import javax.persistence.Entity;
 8 import javax.persistence.GeneratedValue;
 9 import javax.persistence.Id;
10 import javax.persistence.JoinColumn;
11 import javax.persistence.JoinTable;
12 import javax.persistence.ManyToMany;
13 
14 @Entity
15 public class Teacher
16 {
17     private int id;
18     private String name;
19     private Set<Student> allStudent=new HashSet<Student>();
20 
21     @ManyToMany(cascade=CascadeType.ALL)
22     @JoinTable(name = "T_S_fk", joinColumns = { @JoinColumn(name = "tencher_idt") }, inverseJoinColumns = { @JoinColumn(name = "student_ids") })
23     public Set<Student> getAllStudent()
24     {
25         return allStudent;
26     }
27 
28     public void setAllStudent(Set<Student> allStudent)
29     {
30         this.allStudent = allStudent;
31     }
32 
33     @Id
34     @GeneratedValue
35     public int getId()
36     {
37         return id;
38     }
39 
40     public void setId(int id)
41     {
42         this.id = id;
43     }
44 
45     public String getName()
46     {
47         return name;
48     }
49 
50     public void setName(String name)
51     {
52         this.name = name;
53     }
54 }

生成的SQL语句如下：（多对多的关联需要生成中间表，通过@joinTable指定中间表的名称）

View Code

 1 16:38:56,187  INFO SchemaExport:226 - Running hbm2ddl schema export
 2 16:38:56,187 DEBUG SchemaExport:242 - import file not found: /import.sql
 3 16:38:56,187  INFO SchemaExport:251 - exporting generated schema to database
 4 16:38:56,343 DEBUG SchemaExport:377 - 
 5     drop table Student cascade constraints
 6 16:38:56,390 DEBUG SchemaExport:377 - 
 7     drop table T_S_fk cascade constraints
 8 16:38:56,515 DEBUG SchemaExport:377 - 
 9     drop table Teacher cascade constraints
10 16:38:56,515 DEBUG SchemaExport:377 - 
11     drop sequence hibernate_sequence
12 16:38:56,531 DEBUG SchemaExport:377 - 
13     create table Student (
14         id number(10,0) not null,
15         name varchar2(255 char),
16         primary key (id)
17     )
18 16:38:56,578 DEBUG SchemaExport:377 - 
19     create table T_S_fk (
20         tencher_idt number(10,0) not null,
21         student_ids number(10,0) not null,
22         primary key (tencher_idt, student_ids)
23     )
24 16:38:56,625 DEBUG SchemaExport:377 - 
25     create table Teacher (
26         id number(10,0) not null,
27         name varchar2(255 char),
28         primary key (id)
29     )
30 16:38:56,656 DEBUG SchemaExport:377 - 
31     alter table T_S_fk 
32         add constraint FK94B8F93CFF45A8A9 
33         foreign key (tencher_idt) 
34         references Teacher
35 16:38:56,671 DEBUG SchemaExport:377 - 
36     alter table T_S_fk 
37         add constraint FK94B8F93C87009DCD 
38         foreign key (student_ids) 
39         references Student
40 16:38:56,671 DEBUG SchemaExport:377 - 
41     create sequence hibernate_sequence
42 16:38:56,671  INFO SchemaExport:268 - schema export complete

生成的表结构如下：

插入数据测试：

View Code

 1 @Test
 2     public void testTeacher_MTM_Add()
 3     {
 4         Transaction transaction=null;
 5         try
 6         {
 7             Session session=sessionFactory.getCurrentSession();
 8             transaction=session.beginTransaction();
 9             Teacher t=new Teacher();
10             t.setName("张三");
11             t.getAllStudent().add(new Student("李四"));
12             t.getAllStudent().add(new Student("王武"));
13             t.getAllStudent().add(new Student("赵麻子"));
14             session.save(t);            
15             transaction.commit();
16         }
17         catch(Exception e)
18         {
19             e.printStackTrace();
20             transaction.commit();
21         }
22     }

六、补充

1，组件映射通过@Embedded，将另一个实体列表嵌入到一张表中。【Husband-Wife】

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.Embedded;
 4 import javax.persistence.Entity;
 5 import javax.persistence.GeneratedValue;
 6 import javax.persistence.Id;
 7 import javax.persistence.JoinColumn;
 8 import javax.persistence.OneToOne;
 9 
10 @Entity
11 public class Husband
12 {
13     private int id;
14     private String name;
15     private Wife wife=new Wife();
16 
17     @Embedded
18     public Wife getWife()
19     {
20         return wife;
21     }
22 
23     public void setWife(Wife wife)
24     {
25         this.wife = wife;
26     }
27 
28     @Id
29     @GeneratedValue
30     public int getId()
31     {
32         return id;
33     }
34 
35     public void setId(int id)
36     {
37         this.id = id;
38     }
39 
40     public String getName()
41     {
42         return name;
43     }
44 
45     public void setName(String name)
46     {
47         this.name = name;
48     }
49 
50 }

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 public class Wife
 4 {
 5     private int wife_id;
 6     private String wife_name;
 7     private int age;
 8 
 9     public int getWife_id()
10     {
11         return wife_id;
12     }
13 
14     public void setWife_id(int wife_id)
15     {
16         this.wife_id = wife_id;
17     }
18 
19     public String getWife_name()
20     {
21         return wife_name;
22     }
23 
24     public void setWife_name(String wife_name)
25     {
26         this.wife_name = wife_name;
27     }
28 
29     public int getAge()
30     {
31         return age;
32     }
33 
34     public void setAge(int age)
35     {
36         this.age = age;
37     }
38 
39 }

　　2，联合主键通过@JoinColumns指定联合主键的属性名称。【Husband-Wife】

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.Entity;
 4 import javax.persistence.GeneratedValue;
 5 import javax.persistence.Id;
 6 import javax.persistence.JoinColumn;
 7 import javax.persistence.JoinColumns;
 8 import javax.persistence.OneToOne;
 9 import javax.persistence.PrimaryKeyJoinColumn;
10 
11 @Entity
12 public class Husband
13 {
14     private int id;
15     private String name;
16     private Wife wife;
17     
18     @OneToOne
19     @JoinColumns(
20             {
21                 @JoinColumn(name="wifeId",referencedColumnName="id"),
22                 @JoinColumn(name="wifeName",referencedColumnName="name")
23             }
24     )
25     public Wife getWife()
26     {
27         return wife;
28     }
29 
30     public void setWife(Wife wife)
31     {
32         this.wife = wife;
33     }
34 
35     @Id
36     @GeneratedValue
37     public int getId()
38     {
39         return id;
40     }
41 
42     public void setId(int id)
43     {
44         this.id = id;
45     }
46 
47     public String getName()
48     {
49         return name;
50     }
51 
52     public void setName(String name)
53     {
54         this.name = name;
55     }
56 
57 }

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import javax.persistence.CascadeType;
 4 import javax.persistence.EmbeddedId;
 5 import javax.persistence.Entity;
 6 import javax.persistence.OneToOne;
 7 
 8 @Entity
 9 public class Wife
10 {
11     private WifePK wifePK;
12     private int age;
13     private Husband husband=new Husband();
14 
15     @OneToOne(mappedBy = "wife", cascade = CascadeType.ALL)
16     public Husband getHusband()
17     {
18         return husband;
19     }
20 
21     public void setHusband(Husband husband)
22     {
23         this.husband = husband;
24     }
25 
26     @EmbeddedId
27     public WifePK getWifePK()
28     {
29         return wifePK;
30     }
31 
32     public void setWifePK(WifePK wifePK)
33     {
34         this.wifePK = wifePK;
35     }
36 
37     public int getAge()
38     {
39         return age;
40     }
41 
42     public void setAge(int age)
43     {
44         this.age = age;
45     }
46 
47 }

View Code

 1 package org.xiong.hibernate.model;
 2 
 3 import java.io.Serializable;
 4 
 5 public class WifePK implements Serializable
 6 {
 7     /**
 8      * 
 9      */
10     private static final long serialVersionUID = 1L;
11     private int id;
12     private String name;
13 
14     public int getId()
15     {
16         return id;
17     }
18 
19     public void setId(int id)
20     {
21         this.id = id;
22     }
23 
24     public String getName()
25     {
26         return name;
27     }
28 
29     public void setName(String name)
30     {
31         this.name = name;
32     }
33 
34     @Override
35     public int hashCode()
36     {
37         final int prime = 31;
38         int result = 1;
39         result = prime * result + id;
40         result = prime * result + ((name == null) ? 0 : name.hashCode());
41         return result;
42     }
43 
44     @Override
45     public boolean equals(Object obj)
46     {
47         if (this == obj) return true;
48         if (obj == null) return false;
49         if (getClass() != obj.getClass()) return false;
50         WifePK other = (WifePK) obj;
51         if (id != other.id) return false;
52         if (name == null)
53         {
54             if (other.name != null) return false;
55         }
56         else if (!name.equals(other.name)) return false;
57         return true;
58     }
59 
60 }

posted on 2012-05-03 16:49 茫然若失阅读(307) 评论(0) 编辑收藏举报

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