星期日, 一月 10, 2016 ? 16:22
在xml中这种单向的关联该怎么配置
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调试了特么久，结果正确了。
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代码案例:
使用student ? stuidcard进行验证一对一的单向关联
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1.先建一个student类
2.对应的xml文件进行配置
3.再建一个stuidcard类(里面包含一个student类的引用)
4.对应的xml文件进行配置
5.在hibernate.cfg.xml进行指明student类和stuidcard类的位置
6.进行写测试类
7.运行结果
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具体的代码案例:
student类
package com.zhuhw.hibernate.model;
public class Student {
private int id;
private String name;
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;
}
}
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student.hbm.xml文件
/hibernate_0700_One2One_unic_fk/src/com/zhuhw/hibernate/model/Student.hbm.xml
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<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- 找不到entity，是因为这个类没改包名 -->
<hibernate-mapping package="com.zhuhw.hibernate.model">
<class name="Student" table="student" >
<id name="id" >
<generator class="native"></generator>
</id>
<property name="name" />
</class>
</hibernate-mapping>
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/hibernate_0700_One2One_unic_fk/src/com/zhuhw/hibernate/model/StuIdCard.java
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package com.zhuhw.hibernate.model;
public class StuIdCard{
private int id;
private String name;
private Student student;
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 setStudent(Student student) {
this.student = student;
}
public Student getStudent() {
return student;
}
}
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/hibernate_0700_One2One_unic_fk/src/com/zhuhw/hibernate/model/StuIdCard.hbm.xml
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<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- 找不到entity，是因为这个类没改包名 -->
<hibernate-mapping package="com.zhuhw.hibernate.model">
<class name="StuIdCard" table="StuIdCard" >
<id name="id" >
<generator class="native"></generator>
</id>
<property name="name" />
<many-to-one name="Student" column="studentId" unique="true"></many-to-one>
</class>
</hibernate-mapping>
这个一对一的关系的映射有一个需要注意的点，注意name的值
<!-- name指的是 StuIdCard中的student中的一个引用，与这个引用是一样的值-->
<many-to-one name="student" column="studentId" unique="true"></many-to-one>
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/hibernate_0700_One2One_unic_fk/src/hibernate.cfg.xml
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<?xml version=‘1.0‘ encoding=‘utf-8‘?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost/hibernate</property>
<property name="connection.username">root</property>
<property name="connection.password">root</property>
<!--
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:@localhost:1521:orcl</property>
<property name="connection.username">scoot</property>
<property name="connection.password">tiger</property>-->
<!-- JDBC connection pool (use the built-in) -->
<!--<property name="connection.pool_size">1</property>-->
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- Enable Hibernate‘s automatic session context management -->
<property name="current_session_context_class">thread</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<property name="format_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">create</property>
<!-- hibernate去哪里找这个配置文件 -->
<mapping resource="com/zhuhw/hibernate/model/Student.hbm.xml"/>
<mapping resource="com/zhuhw/hibernate/model/StuIdCard.hbm.xml"/><!--
<mapping class="com.zhuhw.hibernate.model.Husband"/>
<mapping class="com.zhuhw.hibernate.model.Wife"/>
--></session-factory>
</hibernate-configuration>
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测试类
/hibernate_0700_One2One_unic_fk/test/com/zhuhw/hibernate/model/HibernateORMappingTest.java
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package com.zhuhw.hibernate.model;
import java.util.Date;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;
public class HibernateORMappingTest {
public static SessionFactory sf = null;
@BeforeClass
public static void beforeClass(){
sf = new AnnotationConfiguration().configure().buildSessionFactory();
}
@Test
public void testOne2One(){
new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
}
@AfterClass
public static void afterClass(){
sf.close();
}
}
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运行结果:
? ? ?console结果:
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create table StuIdCard (
id integer not null auto_increment,
name varchar(255),
studentId integer unique,
primary key (id)
)
16:19:55,274 DEBUG SchemaExport:377 -
create table student (
id integer not null auto_increment,
name varchar(255),
primary key (id)
)
16:19:55,352 DEBUG SchemaExport:377 -
alter table StuIdCard
add index FKD3A449FF7576FD0B (studentId),
add constraint FKD3A449FF7576FD0B
foreign key (studentId)
references student (id)
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此例子完成
原文：http://yuzhouxiner.iteye.com/blog/2270088