对象之间的关系
数据库之间的关系只有外键
注意说关系的时候一定要反面也要说通
CRUD
数据库之间设计
主键关联
单向的外键关联
中间表
一对一单向外键关联
Husband.java
package com.bjsxt.hibernate; import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne; @Entity
public class Husband {
private int id;
private String name;
private Wife wife;
@Id
@GeneratedValue
public int getId() {
return id;
} public String getName() {
return name;
}
public void setId(int id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setWife(Wife wife) {
this.wife = wife;
} }
Wife.java
package com.bjsxt.hibernate; import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id; @Entity
public class Wife {
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;
} }
运行
@Test
public void testSchemaExport() {
new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
}
可以改掉wife_id的名字
XML中
Student.java
package com.bjsxt.hibernate;
public class Student {
private int id;
private String name;
private int age;
private String sex;
private boolean good;
public boolean isGood() {
return good;
}
public void setGood(boolean good) {
this.good = good;
}
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;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
}
Stuidcard.java
package com.bjsxt.hibernate;
public class StuIdCard {
private int id;
private String num;
private Student student;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getNum() {
return num;
}
public void setNum(String num) {
this.num = num;
}
public Student getStudent() {
return student;
}
public void setStudent(Student student) {
this.student = student;
}
}
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"> <hibernate-mapping>
<class name="com.bjsxt.hibernate.Student" dynamic-update="true">
<id name="id">
<generator class="native"></generator>
</id> <property name="name"></property>
<property name="age" />
<property name="sex" />
<property name="good" type="yes_no"></property>
</class> </hibernate-mapping>
stuidcard.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"> <hibernate-mapping>
<class name="com.bjsxt.hibernate.StuIdCard">
<id name="id">
<generator class="native"></generator>
</id> <property name="num"/>
<many-to-one name="student" column="studentId" unique="true"></many-to-one>
</class> </hibernate-mapping>
配置文件
<mapping class="com.bjsxt.hibernate.Husband"/>
<mapping class="com.bjsxt.hibernate.Wife"/>
运行测试
@Test
public void testSchemaExport() {
new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
}