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（摘自互联网，备份）Hibernate实体关系：双向关联，mappedBy必设
注解方式
1、一对一单向
@Entity
public class Husband{
@Id
@GenerateValue
pirvate int id;
private String name;
@OneToOne
@JoinColumn(name="wifeId")
private Wife wife;
}
@Entity
public class Wife{
@Id
@GenerateValue
private int id;
private String name;
}
2.、一对一双向
@Entity
public class Husband{
@Id
@GenerateValue
pirvate int id;
private String name;
@OneToOne
@JoinColumn(name="wifeId")
private Wife wife;
}
@Entity
public class Wife{
@Id
@GenerateValue
private int id;
private String name;
@OneToOne(mappedBy="wife")
private Husband husband;
}
3.、一对多单向
package com.bjsxt.hibernate;
import java.util.HashSet;
import java.util.Set;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import javax.persistence.Table;
@Entity
@Table(name="t_group")
public class Group {
private int id;
private String name;
private Set<User> users = new HashSet<User>();
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@OneToMany
@JoinColumn(name="groupId") //不加出现3张表
public Set<User> getUsers() {
return users;
}
public void setUsers(Set<User> users) {
this.users = users;
}
}
package com.bjsxt.hibernate;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
@Entity
@Table(name="t_user")
public class User {
private int id;
private String name;
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
4、多对一单向
package com.bjsxt.hibernate;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name="t_group")
public class Group {
private int id;
private String name;
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
package com.bjsxt.hibernate;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
@Entity
@Table(name="t_user")
public class User {
private int id;
private String name;
private Group group;
@ManyToOne
public Group getGroup() {
return group;
}
public void setGroup(Group group) {
this.group = group;
}
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
5、一对多双向
package com.bjsxt.hibernate;
import java.util.HashSet;
import java.util.Set;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import javax.persistence.Table;
@Entity
@Table(name="t_group")
public class Group {
private int id;
private String name;
private Set<User> users = new HashSet<User>();
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@OneToMany(mappedBy="group")
public Set<User> getUsers() {
return users;
}
public void setUsers(Set<User> users) {
this.users = users;
}
}
package com.bjsxt.hibernate;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
@Entity
@Table(name="t_user")
public class User {
private int id;
private String name;
private Group group;
@ManyToOne
public Group getGroup() {
return group;
}
public void setGroup(Group group) {
this.group = group;
}
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
6、多对多单向
@Entity
public class Student {
private int id;
private String name;
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
@Entity
public class Teacher {
private int id;
private String name;
private Set<Student> students = new HashSet<Student>();
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@ManyToMany
@JoinTable(name="t_s",
joinColumns={@JoinColumn(name="teacher_id")},
inverseJoinColumns={@JoinColumn(name="student_id")}
) //改变中间表的名字和字段名字
public Set<Student> getStudents() {
return students;
}
public void setStudents(Set<Student> students) {
this.students = students;
}
}
7、多对多双向
@Entity
public class Student {
private int id;
private String name;
private Set<Teacher> teachers = new HashSet<Teacher>();
@ManyToMany(mappedBy="students")
public Set<Teacher> getTeachers() {
return teachers;
}
public void setTeachers(Set<Teacher> teachers) {
this.teachers = teachers;
}
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
@Entity
public class Teacher {
private int id;
private String name;
private Set<Student> students = new HashSet<Student>();
@Id
@GeneratedValue
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@ManyToMany
@JoinTable(name="t_s",
joinColumns={@JoinColumn(name="teacher_id")},
inverseJoinColumns={@JoinColumn(name="student_id")}
)
public Set<Student> getStudents() {
return students;
}
public void setStudents(Set<Student> students) {
this.students = students;
}
}
XML配置
1、一对一单向
<class name="Person">
<id name="id" column="personId">
<generator class="native"/>
</id>
<many-to-one name="address"
column="addressId"
unique="true"
not-null="true"/>
</class>
<class name="Address">
<id name="id" column="addressId">
<generator class="native"/>
</id>
</class>
2.、一对一双向
<class name="Person">
<id name="id" column="personId">
<generator class="native"/>
</id>
<many-to-one name="address"
column="addressId"
unique="true"
not-null="true"/>
</class>
<class name="Address">
<id name="id" column="addressId">
<generator class="native"/>
</id>
<one-to-one name="person"
property-ref="address"/>
</class>
3.、一对多单向
<class name="Person">
<id name="id" column="personId">
<generator class="native"/>
</id>
<set name="addresses">
<key column="personId"
not-null="true"/>
<one-to-many class="Address"/>
</set>
</class>
<class name="Address">
<id name="id" column="addressId">
<generator class="native"/>
</id>
</class>
4、多对一单向
<class name="Person">
<id name="id" column="personId">
<generator class="native"/>
</id>
<many-to-one name="address"
column="addressId"
not-null="true"/>
</class>
<class name="Address">
<id name="id" column="addressId">
<generator class="native"/>
</id>
</class>
5、一对多双向
<hibernate-mapping>
<class name="com.bjsxt.hibernate.Group" table="t_group">
<id name="id">
<generator class="native"></generator>
</id>
<property name="name"></property>
<set name="users" inverse=”true”>
<key column="groupId"></key> //与<many-to-one>的column一致
<one-to-many class="com.bjsxt.hibernate.User"/>
</set>
</class>
</hibernate-mapping>
<hibernate-mapping>
<class name="com.bjsxt.hibernate.User" table="t_user">
<id name="id">
<generator class="native"></generator>
</id>
<property name="name"></property>
<many-to-one name="group" column="groupId"></many-to-one>
</class>
</hibernate-mapping>
6、多对多单向
<hibernate-mapping>
<class name="com.bjsxt.hibernate.Student">
<id name="id">
<generator class="native"></generator>
</id>
<property name="name"></property>
</class>
</hibernate-mapping>
<hibernate-mapping>
<class name="com.bjsxt.hibernate.Teacher">
<id name="id">
<generator class="native"></generator>
</id>
<property name="name"></property>
<set name="students" table="t_s">
<key column="teacher_id"></key>
<many-to-many class="com.bjsxt.hibernate.Student" column="student_id"/>
</set>
</class>
</hibernate-mapping>
7、多对多双向
<hibernate-mapping>
<class name="com.bjsxt.hibernate.Student">
<id name="id">
<generator class="native"></generator>
</id>
<property name="name"></property>
<set name="teachers" table="t_s" inverse=”true”>
<key column="student_id"></key>
<many-to-many class="com.bjsxt.hibernate.Teacher" column="teacher_id"/>
</set>
</class>
</hibernate-mapping>
<hibernate-mapping>
<class name="com.bjsxt.hibernate.Teacher">
<id name="id">
<generator class="native"></generator>
</id>
<property name="name"></property>
<set name="students" table="t_s">
<key column="teacher_id"></key>
<many-to-many class="com.bjsxt.hibernate.Student" column="student_id"/>
</set>
</class>
</hibernate-mapping>
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CXF simple frontend, allow all SSL certificates and set basic authentication cre
2011-09-26 11:53 1744（转自http://blog.progs.be/71/cxf- ... -
spring3+hibernate3.3.5出现的问题
2011-07-06 13:52 1499项目中使用spring3.0.3+hibernate3.3.5 ... -
illegal attempt to dereference collection
2010-10-26 08:58 2003使用中遇到此问题，网上搜索是版本的问题! 例如： from ... -
基于 Struts 2 拦截器实现细粒度的基于角色的存取控制（转）
2010-08-20 14:27 731本文介绍如何利用 Struts ... -
IntelliJ Cannot run web applications in Tomcat with port 8080
2009-08-13 23:07 1091杀毒软件是ESET NOD32，处理方法把ESET NOD32 ... -
在struts2中使用freemarker
2009-07-25 16:10 1597普通的struts2配置文件一 ... -
清理缓存--jsp
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