Hibernate学习笔记3.2（Hibernate组建映射）
1.组建映射
可以存在一个表里面
Husband.java
package com.bjsxt.hibernate; import javax.persistence.Embedded;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinColumns;
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;
}
@Embedded
public Wife getWife() {
return wife;
}
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;
public class Wife {
private String wifeName;
private int age;
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getWifeName() {
return wifeName;
}
public void setWifeName(String name) {
this.wifeName = name;
}
}
HibernateORMappingTest.java
package com.bjsxt.hibernate; 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 {
private static SessionFactory sessionFactory; //@BeforeClass
public static void beforeClass() {
sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
}
//@AfterClass
public static void afterClass() {
sessionFactory.close();
} @Test
public void testSchemaExport() {
new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
} public static void main(String[] args) {
beforeClass();
}
}
也可以使用XML
Husband.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.Husband" >
<id name="id">
<generator class="native"></generator>
</id> <property name="name"></property>
<component name="wife">
<property name="wifeName"></property>
<property name="age"></property>
</component>
</class> </hibernate-mapping>
如果两个对象有属性一致 可以更改属性名 或者使用注解更改 映射的字段名
多对多和一对多
在多的一方加外键
1.annotation
Group.java
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;
}
}
User.java
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;
}
}
hibernate.cfg.xml
<?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> <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">bjsxt</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!--
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:@localhost::SXT</property>
<property name="connection.username">scott</property>
<property name="connection.password">tiger</property>
<property name="dialect">org.hibernate.dialect.OracleDialect</property>
--> <!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size"></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">update</property>
--> <mapping class="com.bjsxt.hibernate.Group"/>
<mapping class="com.bjsxt.hibernate.User"/>
<!--
<mapping resource="com/bjsxt/hibernate/Group.hbm.xml"/>
<mapping resource="com/bjsxt/hibernate/User.hbm.xml"/>
-->
</session-factory> </hibernate-configuration>
test.java
package com.bjsxt.hibernate; 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 {
private static SessionFactory sessionFactory; //@BeforeClass
public static void beforeClass() {
sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
}
//@AfterClass
public static void afterClass() {
sessionFactory.close();
} @Test
public void testSchemaExport() {
new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
} public static void main(String[] args) {
beforeClass();
}
}
2.xml
Group.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.Group" table="t_group">
<id name="id">
<generator class="native"></generator>
</id> <property name="name"></property> </class> </hibernate-mapping>
User.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.User" table="t_user">
<id name="id">
<generator class="native"></generator>
</id> <property name="name"></property>
<many-to-one name="group" column="groupId" />
</class> </hibernate-mapping>
hibernate.cfg.xml
<?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> <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">bjsxt</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!--
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:@localhost::SXT</property>
<property name="connection.username">scott</property>
<property name="connection.password">tiger</property>
<property name="dialect">org.hibernate.dialect.OracleDialect</property>
--> <!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size"></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">update</property>
-->
<!--
<mapping class="com.bjsxt.hibernate.Group"/>
<mapping class="com.bjsxt.hibernate.User"/> -->
<mapping resource="com/bjsxt/hibernate/Group.hbm.xml"/>
<mapping resource="com/bjsxt/hibernate/User.hbm.xml"/> </session-factory> </hibernate-configuration>
test.java一致
一对多的单向关联
在多的方向加外键
Group.java
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")
public Set<User> getUsers() {
return users;
}
public void setUsers(Set<User> users) {
this.users = users;
}
}
如果不加@JoinColumv 变会生成多对多的关系
User.java
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;
}
}
测试
package com.bjsxt.hibernate; 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 {
private static SessionFactory sessionFactory; //@BeforeClass
public static void beforeClass() {
sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
}
//@AfterClass
public static void afterClass() {
sessionFactory.close();
} @Test
public void testSchemaExport() {
new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
} public static void main(String[] args) {
beforeClass();
}
}
2 xml
Group.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.Group" table="t_group">
<id name="id">
<generator class="native"></generator>
</id> <property name="name"></property>
<set name="users">
<key column="groupId"></key>
<one-to-many class="com.bjsxt.hibernate.User"/>
</set>
</class> </hibernate-mapping>
User.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.User" table="t_user">
<id name="id">
<generator class="native"></generator>
</id> <property name="name"></property> </class> </hibernate-mapping>
hibernate.cfg.xml
<?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> <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">bjsxt</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!--
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:@localhost::SXT</property>
<property name="connection.username">scott</property>
<property name="connection.password">tiger</property>
<property name="dialect">org.hibernate.dialect.OracleDialect</property>
--> <!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size"></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">update</property>
-->
<!--
<mapping class="com.bjsxt.hibernate.Group"/>
<mapping class="com.bjsxt.hibernate.User"/> -->
<mapping resource="com/bjsxt/hibernate/Group.hbm.xml"/>
<mapping resource="com/bjsxt/hibernate/User.hbm.xml"/> </session-factory> </hibernate-configuration>
一对多双向
Group.java
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;
}
}
User.java
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;
}
}
hibernate.cfg.xml
<?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> <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">bjsxt</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!--
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:@localhost::SXT</property>
<property name="connection.username">scott</property>
<property name="connection.password">tiger</property>
<property name="dialect">org.hibernate.dialect.OracleDialect</property>
--> <!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size"></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">update</property>
--> <mapping class="com.bjsxt.hibernate.Group"/>
<mapping class="com.bjsxt.hibernate.User"/> <!--
<mapping resource="com/bjsxt/hibernate/Group.hbm.xml"/>
<mapping resource="com/bjsxt/hibernate/User.hbm.xml"/>
-->
</session-factory> </hibernate-configuration>
HibernateORMappingTest.java
package com.bjsxt.hibernate; 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 {
private static SessionFactory sessionFactory; //@BeforeClass
public static void beforeClass() {
sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
}
//@AfterClass
public static void afterClass() {
sessionFactory.close();
} @Test
public void testSchemaExport() {
new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
} public static void main(String[] args) {
beforeClass();
}
}
2.xml方式
<?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.Group" table="t_group">
<id name="id">
<generator class="native"></generator>
</id> <property name="name"></property>
<set name="users">
<key column="groupId"></key>
<one-to-many class="com.bjsxt.hibernate.User"/>
</set>
</class> </hibernate-mapping>
User.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.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>
hibernate.cfg.XML
<?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> <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">bjsxt</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!--
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:@localhost::SXT</property>
<property name="connection.username">scott</property>
<property name="connection.password">tiger</property>
<property name="dialect">org.hibernate.dialect.OracleDialect</property>
--> <!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size"></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">update</property>
-->
<!--
<mapping class="com.bjsxt.hibernate.Group"/>
<mapping class="com.bjsxt.hibernate.User"/>
--> <mapping resource="com/bjsxt/hibernate/Group.hbm.xml"/>
<mapping resource="com/bjsxt/hibernate/User.hbm.xml"/> </session-factory> </hibernate-configuration>
TEST一致
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