慕課網_《Hibernate註解》學習總結
時間：2017年07月11日星期二
說明：本文部份內容均來自慕課網。@慕課網：http://www.imooc.com
教學源碼：無
學習源碼：https://github.com/zccodere/s...java
第一章：類級別註解
1-1 本章簡介
本章簡介mysql
Hibernate註解簡介 JPA與Hibernate的關係 Hibernate註解分類 @Entity @Table @Embeddable schema與catalog
Hibernate註解簡介git
使用註解的目的：爲了簡化繁瑣的ORM映射文件（*.hbm）的配置
JPA與Hibernate的關係github
什麼是JPA
全稱Java Persistence API
JPA註解是JavaEE的規範和標準
JPA和Hibernate的關係：
JPA是標準接口
Hibernate是實現，可是其功能是JPA的超集sql
Hibernate如何實現與JPA的關係
經過hibernate-annotation
hibernate-entitymanager
hibernate-core三個組件來實現
通常在實際開發中，優先考慮使用JPA註解
這樣更有利於程序的移植和擴展
Hibernate註解的分類數據庫
類級別註解 屬性級別註解 映射關係註解
類級別註解apache
@Entity：表示一個實體，一個實體對應數據庫一張表 @Table：配置表的屬性 @Embeddable：表示當前類是一個嵌入類
1-2 準備工做
回顧hibernate.cfg.xml網絡
建立一個名爲hibernateca的maven項目，並添加相關依賴。POM文件以下session
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.myimooc</groupId>
<artifactId>hibernateca</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>hibernateca</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
</properties>
<dependencies>
<!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>4.2.4.Final</version>
</dependency>
<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.38</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.10</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
在src/main/ resources目錄下，建立hibernate.cfg.xml文件app
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">root</property>
<property name="hibernate.connection.url">
<![CDATA[
jdbc:mysql://localhost:3306/hibernatemtm?useUnicode=true&characterEncoding=utf8
]]>
</property>
<property name="show_sql">true</property>
<property name="hbm2ddl.auto">update</property>
<!-- 指定映射文件的路徑 -->
<mapping class="com.myimooc.hibernateca.entity.Students"/>
</session-factory>
</hibernate-configuration>
1-3 @Entity註解
@Entity
@Entity：映射實體類 @Entity(name=」tableName」) name：可選，對應數據庫中的一個表。若表名與實體類名相同，則能夠省略 注意：使用@Entity時必須指定實體類的主鍵屬性
代碼演示
1.編寫Students實體類
package com.myimooc.hibernateca.entity;
import java.util.Date;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
/**
* 學生實體類
* @author ZhangCheng on 2017-07-12
*
*/
//JPA註解
@Entity(name="t_students")
public class Students {
/** 學號 */
@Id
private Integer sid;
/** 姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + sname + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
super();
}
public Students(Integer sid, String sname, String gender, Date birthday, String major) {
super();
this.sid = sid;
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
this.address = address;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
2.配置映射
<!-- 指定映射文件的路徑 --> <mapping class="com.myimooc.hibernateca.entity.Students"/>
3.編寫StudentTest測試類
package com.myimooc.hibernateca.entity;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Test;
/**
* 單元測試類
* @author ZhangCheng on 2017-07-12
*
*/
public class StudentsTest {
@Test
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
@SuppressWarnings("unused")
SessionFactory sessionFactory = config.buildSessionFactory(ServiceRegistry);
SchemaExport export = new SchemaExport(config);
export.create(true, true);
}
}
1-4 @Table註解
@Table
@Table(name=」」,catalog=」」,schema=」」) @Entity配置使用，只能標註在實體的class定義處，表示實體對應的數據庫表的信息 name：可選，映射表的名稱，默認表名和實體名稱一致，只有在不一致的狀況下才須要指定表名 catalog：可選，表示目錄Catalog名稱，默認爲Catalog(「」) schema：可選，表示模式Schema名稱，默認爲Schema(「」)
schema與catalog示意圖
schema與catalog
從實現的角度來看，各類數據庫系統對Catalog和Schema的支持和實現方式千差萬別的
供應商的支持和實現
代碼演示，修改Student類以下
package com.myimooc.hibernateca.entity;
import java.util.Date;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
/**
* 學生實體類
* @author ZhangCheng on 2017-07-12
*
*/
//JPA註解
//@Entity(name="t_students")
@Entity
@Table(name="t_students",schema="hibernatemtm")
public class Students {
/** 學號 */
@Id
private Integer sid;
/** 姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + sname + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
super();
}
public Students(Integer sid, String sname, String gender, Date birthday, String major) {
super();
this.sid = sid;
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
1-5 @Embeddable註解
@Embeddable
@Embeddable表示一個非Entity類能夠嵌入到另外一個Entity類中做爲屬性而存在
代碼演示
1.編寫Address類
package com.myimooc.hibernateca.entity;
import javax.persistence.Embeddable;
/**
* 地址類（嵌入類）
* @author ZhangCheng on 2017-07-12
*
*/
// 表示是一個嵌入類，這個類的對象在另外一個實體類中充當屬性
@Embeddable
public class Address {
/** 郵編 */
private String postCode;
/** 地址 */
private String address;
/** 聯繫電話 */
private String phone;
@Override
public String toString() {
return "Address [postCode=" + postCode + ", address=" + address + ", phone=" + phone + "]";
}
public Address() {
}
public Address(String postCode, String address, String phone) {
this.postCode = postCode;
this.address = address;
this.phone = phone;
}
public String getPostCode() {
return postCode;
}
public void setPostCode(String postCode) {
this.postCode = postCode;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
}
2.修改Student類以下
package com.myimooc.hibernateca.entity;
import java.util.Date;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
/**
* 學生實體類
* @author ZhangCheng on 2017-07-12
*
*/
//JPA註解
//@Entity(name="t_students")
@Entity
@Table(name="t_students",schema="hibernatemtm")
public class Students {
/** 學號 */
@Id
private Integer sid;
/** 姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
/** 地址 */
private Address address;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + sname + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
super();
}
public Students(Integer sid, String sname, String gender, Date birthday, String major,Address address) {
super();
this.sid = sid;
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
this.address = address;
}
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
第二章：屬性級別註解
2-1 本章簡介
Hibernate屬性級別註解
添加方式：寫在屬性字段方面 或 寫在屬性的get訪問器的上面 @Id -@SequenceGenerator @GeneratedValue @Column @Embedded @EmbeddedId -@Lob -@Version -@Basic @Transient
2-2 @Id註解
@Id
@Id：必須，定義了映射到數據庫表的主鍵的屬性， 一個實體類能夠有一個或者多個屬性被映射爲主鍵， 可置於主鍵屬性或者get方法前 注意：若是有多個屬性定義爲主鍵屬性， 該實體類必須實現serializable接口
拷貝hibernateca項目，重命名爲hibernateaa，POM與Hibernate配置文件均相同
2-3 @GeneratedValue註解（一）
@GeneratedValue
@GeneratedValue(strategy=GenerationType,generator=」」)
可選，用戶定義主鍵生成策略
strategy表示主鍵生成策略，取值有
GenerationType.AUTO:根據底層數據庫自動選擇（默認）
GenerationType.INDENTITY：根據數據庫的Identity字段生成
GenerationType.SEQUENCE：使用Sequence來決定主鍵的取值
GenerationType.TABLE：使用指定表來決定主鍵取值，結合@TableGenerator使用
使用示例
2-4 @GeneratedValue註解（二）
代碼演示
1.修改Students類
package com.myimooc.hibernateaa.entity;
import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Embedded;
import javax.persistence.EmbeddedId;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.persistence.Transient;
import org.hibernate.annotations.GenericGenerator;
/**
* 學生實體類
* @author ZhangCheng on 2017-07-12
*
*/
@SuppressWarnings("unused")
@Entity
@Table(name="t_students",schema="hibernatemtm")
public class Students {
/** 學號 */
/* 方式一：使用自動生成主鍵
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Integer sid;
*/
/* 方式二：使用手工賦值方式生成主鍵
@Id
@GeneratedValue(generator="sid")
@GenericGenerator(name="sid",strategy="assigned")//
@Column(length=8)
private String sid;
*/
/* 方式三：使用複合主鍵 */
@EmbeddedId
private StudentsPK pk;
/** 姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
/** 薪水 */
@Transient // 表示該屬性不會被ORM映射到表裏的字段
private double salary;
/** 地址 */
@Embedded
private Address address;
@Override
public String toString() {
return "Students [pk=" + pk + ", sname=" + sname + ", gender=" + gender + ", birthday=" + birthday + ", major="
+ major + ", salary=" + salary + ", address=" + address + "]";
}
public Students() {
super();
}
public Students(StudentsPK pk, String sname, String gender, Date birthday, String major,Address address) {
super();
this.pk = pk;
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
this.address = address;
}
public Students(StudentsPK pk, String sname, String gender, Date birthday, String major, double salary,
Address address) {
super();
this.pk = pk;
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
this.salary = salary;
this.address = address;
}
public double getSalary() {
return salary;
}
public void setSalary(double salary) {
this.salary = salary;
}
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
public StudentsPK getPk() {
return pk;
}
public void setPk(StudentsPK pk) {
this.pk = pk;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
2-5 @GeneratedValue註解（三）
代碼演示
1.修改StudentsTest類
package com.myimooc.hibernateaa.entity;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 單元測試類
* @author ZhangCheng on 2017-07-12
*
*/
@SuppressWarnings("unused")
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
// SchemaExport export = new SchemaExport(config);
// export.create(true, true);
}
@Test
public void addStudents(){
// 建立會話
Session session = sessionFactory.getCurrentSession();
// 建立事務
Transaction tx = session.beginTransaction();
// 建立一個學生對象
Address address = new Address("700005","湖北武當山","18991167346");
// Students s = new Students("S0000002","張三丰","男",new Date(),"太極拳",address);
//
// session.save(s);
tx.commit();
}
@Test
public void addStudentsByPk(){
// 建立會話
Session session = sessionFactory.getCurrentSession();
// 建立事務
Transaction tx = session.beginTransaction();
// 建立一個學生對象
Address address = new Address("700005","湖北武當山","18991167346");
// 建立學生主鍵對象
StudentsPK pk = new StudentsPK();
pk.setId("123456789012345678");
pk.setSid("1235241231");
Students s = new Students(pk,"張三丰","男",new Date(),"太極拳",address);
session.save(s);
tx.commit();
}
}
2-6 @Column註解
@Column
@Column：可將屬性映射到列，使用該註解來覆蓋默認值 @Column描述了數據庫表中該字段的詳細定義 這對於根據JPA註解生成數據庫表結構的工具很是有做用
經常使用屬性
name：可選，表示數據庫表中該字段的名稱，默認與屬性名稱一致
nullable：可選，表示該字段是否容許爲null，默認爲true
unique：可選，表示該字段是不是惟一標識，默認爲false
length：可選，表示該字段的大小，僅對String類型的字段有效，默認爲255
（若是是主鍵不能使用默認值）
insertable：可選，表示在ORM框架執行插入操做時，該字段是否應出現INSERT語句中，默認爲true
updateable：可選，表示在ORM框架執行更新操做時，該字段是否應該出如今UPDATE語句中，默認爲true
對於一經建立就不能夠更改的字段，該屬性很是有用，如對於birthday字段
2-7 @Embedded註解
@Embedded
@Embedded是註釋屬性的，表示該屬性的類是嵌入類 注意：同時嵌入類也必須標註@Embeddable註解
2-8 @EmbeddedId註解
@EmbeddedId
@EmbeddedId使用嵌入式主鍵類實現複合主鍵 注意：嵌入式主鍵類 必須實現Serializable接口 必須有默認的public無參數的構造方法 必須覆蓋equals和hashCode方法
代碼演示
1.編寫StudentsPK類
package com.myimooc.hibernateaa.entity;
import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Embeddable;
/**
* 學生主鍵類
* @author ZhangCheng on 2017-07-12
*
*/
@Embeddable
public class StudentsPK implements Serializable{
private static final long serialVersionUID = 1L;
/** 省份證號碼 */
@Column(length=18)
private String id;
/** 學號 */
@Column(length=10)
private String sid;
public StudentsPK() {
}
@Override
public String toString() {
return "StudentsPK [id=" + id + ", sid=" + sid + "]";
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((id == null) ? 0 : id.hashCode());
result = prime * result + ((sid == null) ? 0 : sid.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
StudentsPK other = (StudentsPK) obj;
if (id == null) {
if (other.id != null)
return false;
} else if (!id.equals(other.id))
return false;
if (sid == null) {
if (other.sid != null)
return false;
} else if (!sid.equals(other.sid))
return false;
return true;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getSid() {
return sid;
}
public void setSid(String sid) {
this.sid = sid;
}
}
2.修改Students類
package com.myimooc.hibernateaa.entity;
import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Embedded;
import javax.persistence.EmbeddedId;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.persistence.Transient;
import org.hibernate.annotations.GenericGenerator;
/**
* 學生實體類
* @author ZhangCheng on 2017-07-12
*
*/
@SuppressWarnings("unused")
@Entity
@Table(name="t_students",schema="hibernatemtm")
public class Students {
/** 學號 */
/* 方式一：使用自動生成主鍵
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Integer sid;
*/
/* 方式二：使用手工賦值方式生成主鍵
@Id
@GeneratedValue(generator="sid")
@GenericGenerator(name="sid",strategy="assigned")//
@Column(length=8)
private String sid;
*/
/* 方式三：使用複合主鍵 */
@EmbeddedId
private StudentsPK pk;
/** 姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
/** 薪水 */
@Transient // 表示該屬性不會被ORM映射到表裏的字段
private double salary;
/** 地址 */
@Embedded
private Address address;
@Override
public String toString() {
return "Students [pk=" + pk + ", sname=" + sname + ", gender=" + gender + ", birthday=" + birthday + ", major="
+ major + ", salary=" + salary + ", address=" + address + "]";
}
public Students() {
super();
}
public Students(StudentsPK pk, String sname, String gender, Date birthday, String major,Address address) {
super();
this.pk = pk;
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
this.address = address;
}
public Students(StudentsPK pk, String sname, String gender, Date birthday, String major, double salary,
Address address) {
super();
this.pk = pk;
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
this.salary = salary;
this.address = address;
}
public double getSalary() {
return salary;
}
public void setSalary(double salary) {
this.salary = salary;
}
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
public StudentsPK getPk() {
return pk;
}
public void setPk(StudentsPK pk) {
this.pk = pk;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
3.修改StudentsTest類
package com.myimooc.hibernateaa.entity;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 單元測試類
* @author ZhangCheng on 2017-07-12
*
*/
@SuppressWarnings("unused")
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
// SchemaExport export = new SchemaExport(config);
// export.create(true, true);
}
@Test
public void addStudents(){
// 建立會話
Session session = sessionFactory.getCurrentSession();
// 建立事務
Transaction tx = session.beginTransaction();
// 建立一個學生對象
Address address = new Address("700005","湖北武當山","18991167346");
// Students s = new Students("S0000002","張三丰","男",new Date(),"太極拳",address);
//
// session.save(s);
tx.commit();
}
@Test
public void addStudentsByPk(){
// 建立會話
Session session = sessionFactory.getCurrentSession();
// 建立事務
Transaction tx = session.beginTransaction();
// 建立一個學生對象
Address address = new Address("700005","湖北武當山","18991167346");
// 建立學生主鍵對象
StudentsPK pk = new StudentsPK();
pk.setId("123456789012345678");
pk.setSid("1235241231");
Students s = new Students(pk,"張三丰","男",new Date(),"太極拳",address);
session.save(s);
tx.commit();
}
}
2-9 @Transient註解
@Transient
可選，表示該屬性並不是一個到數據庫表的字段的映射，ORM框架將忽略該屬性，若是一個屬性並不是數據庫表的字段映射，就務必將其表示爲@Transient，不然ORM框架默認其註解爲@Basic
第三章：關聯映射註解
3-1 本章簡介
簡介
一對一單向外鍵關聯 一對一雙向外鍵關聯 一對一單向外鍵聯合主鍵 多對一單向外鍵關聯 一對多單向外鍵關聯 一對多雙向外鍵關聯 多對多單向外鍵關聯 多對多雙向外鍵關聯
3-2 實體之間的關係
實體之間的映射關係
一對一：一個公民對應一個身份證號碼 一對多（多對一）：一個公民有多個銀行帳號 多對多：一個學生有多個老師，一個老師有多個學生
3-3 一對一單向外鍵關聯（一）
一對一單向外鍵
@OneToOne(cascade=CascadeType.ALL) @JoinColumn(name=」pid」,unique=true) 注意：保存時應該先保存外鍵對象，再保存主表對象
拷貝hibernateca項目，重命名爲hibernatera，POM與Hibernate配置文件均相同
代碼演示
1.編寫Students類
package com.myimooc.hibernatera.onetoonefk;
import java.util.Date;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
/**
* 一對一單向外鍵關聯
* 學生實體類
* @author ZhangCheng on 2017-07-12
*
*/
@Entity
public class Students {
/** 學號 */
@Id
@GeneratedValue
private Integer sid;
/** 身份證類 */
@OneToOne(cascade=CascadeType.ALL)
@JoinColumn(name="pid",unique=true)
private IdCard card;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
}
public Students(IdCard card, String gender, Date birthday, String major) {
super();
this.card = card;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public Students(IdCard card,Integer sid, String gender, Date birthday, String major) {
this.card = card;
this.sid = sid;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public IdCard getCard() {
return card;
}
public void setCard(IdCard card) {
this.card = card;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
2.編寫IdCard類
package com.myimooc.hibernatera.onetoonefk;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import org.hibernate.annotations.GenericGenerator;
/**
* 一對一單向外鍵關聯
* 身份證明體類
* @author ZhangCheng on 2017-07-12
*
*/
@Entity
public class IdCard {
@Id
@GeneratedValue(generator = "pid")
@GenericGenerator(name="pid",strategy="assigned")
@Column(length=18)
/** 身份證號碼 */
private String pid;
/** 學生的姓名 */
private String sname;
public IdCard() {
}
public IdCard(String pid, String sname) {
this.pid = pid;
this.sname = sname;
}
public String getPid() {
return pid;
}
public void setPid(String pid) {
this.pid = pid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
}
3.修改Hibernate配置文件
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">root</property>
<property name="hibernate.connection.url">
<![CDATA[
jdbc:mysql://localhost:3306/hibernatemtm?useUnicode=true&characterEncoding=utf8
]]>
</property>
<property name="show_sql">true</property>
<property name="hbm2ddl.auto">update</property>
<property name="current_session_context_class">thread</property>
<!-- 一對一單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetoonefk.Students"/>
<mapping class="com.myimooc.hibernatera.onetoonefk.IdCard"/>
-->
<!-- 一對一雙向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetoonebfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetoonebfk.IdCard"/>
-->
<!-- 多對一單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.manytoonefk.Students"/>
<mapping class="com.myimooc.hibernatera.manytoonefk.ClassRoom"/>
-->
<!-- 一對多單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetomanyfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetomanyfk.ClassRoom"/>
-->
<!-- 一對多雙向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetomanybfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetomanybfk.ClassRoom"/>
-->
<!-- 多對多單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.manytomanyfk.Students"/>
<mapping class="com.myimooc.hibernatera.manytomanyfk.Teachers"/>
-->
<!-- 多對多雙向外鍵關聯 -->
<mapping class="com.myimooc.hibernatera.manytomanybfk.Students"/>
<mapping class="com.myimooc.hibernatera.manytomanybfk.Teachers"/>
</session-factory>
</hibernate-configuration>
4.編寫StudentsTest類
package com.myimooc.hibernatera.onetoonefk;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 一對一雙單外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-12
*
*/
@SuppressWarnings("unused")
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
// SchemaExport export = new SchemaExport(config);
//
// export.create(true, true);
}
}
3-4 一對一單向外鍵關聯（二）
代碼演示
1.修改StudentsTest類
package com.myimooc.hibernatera.onetoonefk;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 一對一雙單外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-12
*
*/
@SuppressWarnings("unused")
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
// SchemaExport export = new SchemaExport(config);
//
// export.create(true, true);
}
/**
* 一對一單向外鍵關聯保存測試
*/
@Test
public void addStudents(){
Session session = sessionFactory.getCurrentSession();
// 生成一個身份證對象
IdCard card = new IdCard("123456789012345678","張無忌");
Transaction tx = session.beginTransaction();
// 生成學生對象
Students s = new Students(card, "男", new Date(), "太極拳");
// 先保存身份證類的對象
session.save(card);
session.save(s);
tx.commit();
}
}
3-5 一對一雙向外鍵關聯
一對一雙向外鍵
主控方的配置同一對一單向外鍵關聯相同 @OneToOne(mappedBy=」card」)//被控方 雙向關聯，必須設置mappedBy屬性。由於雙向關聯只能交給一方去控制 不可能在雙方都設置外鍵保存關聯關係，不然雙方都沒法保存
代碼演示
1.編寫Students類
package com.myimooc.hibernatera.onetoonebfk;
import java.util.Date;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
/**
* 一對一雙向外鍵關聯
* 學生實體類
* @author ZhangCheng on 2017-07-12
*
*/
@Entity
public class Students {
/** 學號 */
@Id
@GeneratedValue
private Integer sid;
/** 身份證類 */
@OneToOne(cascade=CascadeType.ALL)
@JoinColumn(name="pid",unique=true)
private IdCard card;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
}
public Students(IdCard card, String gender, Date birthday, String major) {
super();
this.card = card;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public Students(IdCard card,Integer sid, String gender, Date birthday, String major) {
this.card = card;
this.sid = sid;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public IdCard getCard() {
return card;
}
public void setCard(IdCard card) {
this.card = card;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
2.編寫IdCard類
package com.myimooc.hibernatera.onetoonebfk;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToOne;
import org.hibernate.annotations.GenericGenerator;
/**
* 一對一雙向外鍵關聯
* 身份證明體類
* @author ZhangCheng on 2017-07-12
*
*/
@Entity
public class IdCard {
@Id
@GeneratedValue(generator = "pid")
@GenericGenerator(name="pid",strategy="assigned")
@Column(length=18)
/** 身份證號碼 */
private String pid;
/** 學生的姓名 */
private String sname;
/** 學生的引用 */
@OneToOne(mappedBy="card")
private Students stu;
public Students getStu() {
return stu;
}
public void setStu(Students stu) {
this.stu = stu;
}
public IdCard() {
}
public IdCard(String pid, String sname) {
this.pid = pid;
this.sname = sname;
}
public String getPid() {
return pid;
}
public void setPid(String pid) {
this.pid = pid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
}
3.修改hibernate配置文件
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">root</property>
<property name="hibernate.connection.url">
<![CDATA[
jdbc:mysql://localhost:3306/hibernatemtm?useUnicode=true&characterEncoding=utf8
]]>
</property>
<property name="show_sql">true</property>
<property name="hbm2ddl.auto">update</property>
<property name="current_session_context_class">thread</property>
<!-- 一對一單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetoonefk.Students"/>
<mapping class="com.myimooc.hibernatera.onetoonefk.IdCard"/>
-->
<!-- 一對一雙向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetoonebfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetoonebfk.IdCard"/>
-->
<!-- 多對一單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.manytoonefk.Students"/>
<mapping class="com.myimooc.hibernatera.manytoonefk.ClassRoom"/>
-->
<!-- 一對多單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetomanyfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetomanyfk.ClassRoom"/>
-->
<!-- 一對多雙向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetomanybfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetomanybfk.ClassRoom"/>
-->
<!-- 多對多單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.manytomanyfk.Students"/>
<mapping class="com.myimooc.hibernatera.manytomanyfk.Teachers"/>
-->
<!-- 多對多雙向外鍵關聯 -->
<mapping class="com.myimooc.hibernatera.manytomanybfk.Students"/>
<mapping class="com.myimooc.hibernatera.manytomanybfk.Teachers"/>
</session-factory>
</hibernate-configuration>
4.編寫StudentsTest類
package com.myimooc.hibernatera.onetoonebfk;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 一對一雙向外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-12
*
*/
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
//@Test
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
SchemaExport export = new SchemaExport(config);
export.create(true, true);
}
/**
* 一對一雙向外鍵關聯保存測試
*/
@Test
public void addStudents(){
Session session = sessionFactory.getCurrentSession();
// 生成一個身份證對象
IdCard card = new IdCard("123456789012345678","張無忌");
Transaction tx = session.beginTransaction();
// 生成學生對象
Students s = new Students(card, "男", new Date(), "太極拳");
// 先保存身份證類的對象
session.save(card);
session.save(s);
tx.commit();
}
}
3-6 一對一單向外鍵聯合主鍵
一對一雙向外鍵聯合主鍵
建立主鍵類 主鍵類必須實現serializable接口，重寫hashCode()和equals()方法 主鍵類：@Embeddable 實體類：@EmbeddedId
3-7 多對一單向外鍵關聯（一）
多對一單向外鍵
多方持有一方的引用，好比：多個學生對應一個班級（多對一）
在多方添加如下註解
@ManyToOne(cascade={CascadeType.ALL},fetch=FetchType.EAGER)
@JoinColumn(name=」cid」,referencedColumnName=」CID」)
代碼演示
1.編寫Students類
package com.myimooc.hibernatera.manytoonefk;
import java.util.Date;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
/**
* 多對一單向外鍵關聯
* 學生實體類（多方）
* @author ZhangCheng on 2017-07-13
*
*/
@Entity
public class Students {
/** 學號 */
@Id
@GeneratedValue
private Integer sid;
/** 學生姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
// 多方持有一方的引用
@ManyToOne(cascade={CascadeType.ALL},fetch=FetchType.EAGER)// 配置級聯關係和抓取策略
@JoinColumn(name="cid",referencedColumnName="CID") // 指定外鍵
private ClassRoom classRoom;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
}
public Students(String sname, String gender, Date birthday, String major) {
super();
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public ClassRoom getClassRoom() {
return classRoom;
}
public void setClassRoom(ClassRoom classRoom) {
this.classRoom = classRoom;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
2.編寫ClassRoom類
package com.myimooc.hibernatera.manytoonefk;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import org.hibernate.annotations.GenericGenerator;
/**
* 多對一單向外鍵關聯
* 班級實體類（一方）
* @author ZhangCheng on 2017-07-13
*
*/
@Entity
public class ClassRoom {
/** 班級編號 */
@Id
@GeneratedValue(generator="cid")
@GenericGenerator(name="cid",strategy="assigned")
@Column(length=4)
private String cid;
/** 班級名字 */
private String cname;
public ClassRoom() {
}
public ClassRoom(String cid, String cname) {
this.cid = cid;
this.cname = cname;
}
public String getCid() {
return cid;
}
public void setCid(String cid) {
this.cid = cid;
}
public String getCname() {
return cname;
}
public void setCname(String cname) {
this.cname = cname;
}
@Override
public String toString() {
return "ClassRoom [cid=" + cid + ", cname=" + cname + "]";
}
}
3.修改hibernate配置文件
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">root</property>
<property name="hibernate.connection.url">
<![CDATA[
jdbc:mysql://localhost:3306/hibernatemtm?useUnicode=true&characterEncoding=utf8
]]>
</property>
<property name="show_sql">true</property>
<property name="hbm2ddl.auto">update</property>
<property name="current_session_context_class">thread</property>
<!-- 一對一單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetoonefk.Students"/>
<mapping class="com.myimooc.hibernatera.onetoonefk.IdCard"/>
-->
<!-- 一對一雙向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetoonebfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetoonebfk.IdCard"/>
-->
<!-- 多對一單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.manytoonefk.Students"/>
<mapping class="com.myimooc.hibernatera.manytoonefk.ClassRoom"/>
-->
<!-- 一對多單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetomanyfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetomanyfk.ClassRoom"/>
-->
<!-- 一對多雙向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.onetomanybfk.Students"/>
<mapping class="com.myimooc.hibernatera.onetomanybfk.ClassRoom"/>
-->
<!-- 多對多單向外鍵關聯 -->
<!--
<mapping class="com.myimooc.hibernatera.manytomanyfk.Students"/>
<mapping class="com.myimooc.hibernatera.manytomanyfk.Teachers"/>
-->
<!-- 多對多雙向外鍵關聯 -->
<mapping class="com.myimooc.hibernatera.manytomanybfk.Students"/>
<mapping class="com.myimooc.hibernatera.manytomanybfk.Teachers"/>
</session-factory>
</hibernate-configuration>
4.編寫StudentsTest類
package com.myimooc.hibernatera.manytoonefk;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 多對一單向外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-13
*
*/
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
//@Test
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
SchemaExport export = new SchemaExport(config);
export.create(true, true);
}
}
3-8 多對一單向外鍵關聯（二）
代碼演示
1.修改StudentsTest類
package com.myimooc.hibernatera.manytoonefk;
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 多對一單向外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-13
*
*/
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
//@Test
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
SchemaExport export = new SchemaExport(config);
export.create(true, true);
}
@Test
public void addStudents(){
Session session = sessionFactory.getCurrentSession();
Transaction tx = session.beginTransaction();
// 建立班級對象
ClassRoom c1 = new ClassRoom("C001","軟件工程");
ClassRoom c2 = new ClassRoom("C002","網絡工程");
// 建立學生對象
Students s1 = new Students("張三","男", new Date(), "計算機");
Students s2 = new Students("李四","男", new Date(), "計算機");
Students s3 = new Students("王五","女", new Date(), "計算機");
Students s4 = new Students("趙六","女", new Date(), "計算機");
s1.setClassRoom(c1);
s2.setClassRoom(c1);
s3.setClassRoom(c2);
s4.setClassRoom(c2);
// 先保存班級
session.save(c1);
session.save(c2);
session.save(s1);
session.save(s2);
session.save(s3);
session.save(s4);
tx.commit();
}
}
3-9 一對多單向外鍵關聯
一對多單向外鍵
一方持有多方的集合，一個班級有多個學生（一對多）
在一方添加如下註解
@OneToMany(cascade={CascadeType.ALL},fetch=FetchType.LAZY)
@JoinColumn(name=」cid」)
抓取策略總結
多對一時候 多方設置EAGER：表示積極加載 一方設置LAZY：表示懶加載
代碼演示
1.編寫Students類
package com.myimooc.hibernatera.onetomanyfk;
import java.util.Date;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
/**
* 一對多單向外鍵關聯
* 學生實體類（多方）
* @author ZhangCheng on 2017-07-13
*
*/
@Entity
public class Students {
/** 學號 */
@Id
@GeneratedValue
private Integer sid;
/** 學生姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
}
public Students(String sname, String gender, Date birthday, String major) {
super();
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
2.編寫ClassRoom類
package com.myimooc.hibernatera.onetomanyfk;
import java.util.Set;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import org.hibernate.annotations.GenericGenerator;
/**
* 一對多單向外鍵關聯
* 班級實體類（一方）
* @author ZhangCheng on 2017-07-13
*
*/
@Entity
public class ClassRoom {
/** 班級編號 */
@Id
@GeneratedValue(generator="cid")
@GenericGenerator(name="cid",strategy="assigned")
@Column(length=4)
private String cid;
/** 班級名字 */
private String cname;
// 一方持有多方的集合
@OneToMany(cascade={CascadeType.ALL},fetch=FetchType.LAZY)
@JoinColumn(name="cid")
private Set<Students> stus;
public ClassRoom() {
}
public ClassRoom(String cid, String cname) {
this.cid = cid;
this.cname = cname;
}
public Set<Students> getStus() {
return stus;
}
public void setStus(Set<Students> stus) {
this.stus = stus;
}
public String getCid() {
return cid;
}
public void setCid(String cid) {
this.cid = cid;
}
public String getCname() {
return cname;
}
public void setCname(String cname) {
this.cname = cname;
}
@Override
public String toString() {
return "ClassRoom [cid=" + cid + ", cname=" + cname + "]";
}
}
3.修改hibernate配置文件
同上
4.編寫StudentsTest類
package com.myimooc.hibernatera.onetomanyfk;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 一對多單向外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-13
*
*/
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
//@Test
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
SchemaExport export = new SchemaExport(config);
export.create(true, true);
}
@Test
public void addStudents(){
Session session = sessionFactory.getCurrentSession();
Transaction tx = session.beginTransaction();
// 建立班級對象
ClassRoom c1 = new ClassRoom("C001","軟件工程");
ClassRoom c2 = new ClassRoom("C002","網絡工程");
// 建立學生對象
Students s1 = new Students("張三","男", new Date(), "計算機");
Students s2 = new Students("李四","男", new Date(), "計算機");
Students s3 = new Students("王五","女", new Date(), "計算機");
Students s4 = new Students("趙六","女", new Date(), "計算機");
// 建立兩個集合
Set<Students> set1 = new HashSet<Students>();
set1.add(s1);
set1.add(s2);
Set<Students> set2 = new HashSet<Students>();
set2.add(s3);
set2.add(s4);
c1.setStus(set1);
c2.setStus(set2);
// 先保存學生
session.save(s1);
session.save(s2);
session.save(s3);
session.save(s4);
session.save(c1);
session.save(c2);
tx.commit();
}
}
3-10 一對多雙向外鍵關聯
一對多（多對一）雙向外鍵
多方：多方持有一方的引用
在多方添加如下註解
@ManyToOne(cascade={CascadeType.ALL},fetch=FetchType.EAGER)
@JoinColumn(name=」cid」)
一方：一方持有多方的集合
在一方添加如下註解
@OneToMany(cascade={CascadeType.ALL},fetch=FetchType.LAZY)
@JoinColumn(name=」cid」)
代碼演示
1.編寫Students類
package com.myimooc.hibernatera.onetomanybfk;
import java.util.Date;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
/**
* 一對多雙向外鍵關聯
* 學生實體類（多方）
* @author ZhangCheng on 2017-07-13
*
*/
@Entity
public class Students {
/** 學號 */
@Id
@GeneratedValue
private Integer sid;
/** 學生姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
// 多方持有一方的引用
@ManyToOne(cascade={CascadeType.ALL},fetch=FetchType.EAGER)// 配置級聯關係和抓取策略
@JoinColumn(name="cid") // 指定外鍵
private ClassRoom classRoom;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
}
public Students(String sname, String gender, Date birthday, String major) {
super();
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
2.編寫ClassRoom類
package com.myimooc.hibernatera.onetomanybfk;
import java.util.Set;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import org.hibernate.annotations.GenericGenerator;
/**
* 一對多雙向外鍵關聯
* 班級實體類（一方）
* @author ZhangCheng on 2017-07-13
*
*/
@Entity
public class ClassRoom {
/** 班級編號 */
@Id
@GeneratedValue(generator="cid")
@GenericGenerator(name="cid",strategy="assigned")
@Column(length=4)
private String cid;
/** 班級名字 */
private String cname;
// 一方持有多方的集合
@OneToMany(cascade={CascadeType.ALL},fetch=FetchType.LAZY)
@JoinColumn(name="cid")
private Set<Students> stus;
public ClassRoom() {
}
public ClassRoom(String cid, String cname) {
this.cid = cid;
this.cname = cname;
}
public Set<Students> getStus() {
return stus;
}
public void setStus(Set<Students> stus) {
this.stus = stus;
}
public String getCid() {
return cid;
}
public void setCid(String cid) {
this.cid = cid;
}
public String getCname() {
return cname;
}
public void setCname(String cname) {
this.cname = cname;
}
@Override
public String toString() {
return "ClassRoom [cid=" + cid + ", cname=" + cname + "]";
}
}
3.修改hibernate配置文件
同上
4.編寫StudentsTest類
package com.myimooc.hibernatera.onetomanybfk;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 一對多雙向外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-13
*
*/
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
//@Test
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
SchemaExport export = new SchemaExport(config);
export.create(true, true);
}
@Test
public void addStudents(){
Session session = sessionFactory.getCurrentSession();
Transaction tx = session.beginTransaction();
// 建立班級對象
ClassRoom c1 = new ClassRoom("C001","軟件工程");
ClassRoom c2 = new ClassRoom("C002","網絡工程");
// 建立學生對象
Students s1 = new Students("張三","男", new Date(), "計算機");
Students s2 = new Students("李四","男", new Date(), "計算機");
Students s3 = new Students("王五","女", new Date(), "計算機");
Students s4 = new Students("趙六","女", new Date(), "計算機");
// 建立兩個集合
Set<Students> set1 = new HashSet<Students>();
set1.add(s1);
set1.add(s2);
Set<Students> set2 = new HashSet<Students>();
set2.add(s3);
set2.add(s4);
c1.setStus(set1);
c2.setStus(set2);
// 先保存學生
session.save(s1);
session.save(s2);
session.save(s3);
session.save(s4);
session.save(c1);
session.save(c2);
tx.commit();
}
}
3-11 多對多單向外鍵關聯（一）
多對多單向外鍵
學生和教師構成多對多的關聯關係
其中一個多方持有另外一個多方的集合對象（學生持有教師的集合）
建立中間表
// 學生類中添加如下註解
@ManyToMany
@JoinTable(
name=」teachers_students」,
joinColumns = {@JoinColumn(name=」sid」)},
inverseJoinColumns={@JoinColumn(name=」tid」)})
代碼演示
1.編寫Students類
package com.myimooc.hibernatera.manytomanyfk;
import java.util.Date;
import java.util.Set;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
/**
* 多對多單向外鍵關聯
* 學生實體類（多方）
* @author ZhangCheng on 2017-07-13
*
*/
@Entity
public class Students {
/** 學號 */
@Id
@GeneratedValue
private Integer sid;
/** 學生姓名 */
private String sname;
/** 性別 */
private String gender;
/** 出生日期 */
private Date birthday;
/** 專業 */
private String major;
// 學生持有教師的集合
@ManyToMany
@JoinTable(
name="teachers_students",
joinColumns={@JoinColumn(name="sid")},
inverseJoinColumns={@JoinColumn(name="tid")}
)
private Set<Teachers> teachers;
@Override
public String toString() {
return "Students [sid=" + sid + ", sname=" + ", gender=" + gender + ", birthday=" + birthday
+ ", major=" + major + "]";
}
public Students() {
}
public Students(String sname, String gender, Date birthday, String major) {
super();
this.sname = sname;
this.gender = gender;
this.birthday = birthday;
this.major = major;
}
public Set<Teachers> getTeachers() {
return teachers;
}
public void setTeachers(Set<Teachers> teachers) {
this.teachers = teachers;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public Integer getSid() {
return sid;
}
public void setSid(Integer sid) {
this.sid = sid;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getMajor() {
return major;
}
public void setMajor(String major) {
this.major = major;
}
}
2.編寫Teachers類
package com.myimooc.hibernatera.manytomanyfk;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import org.hibernate.annotations.GenericGenerator;
/**
* 多對多單向外鍵關聯
* 教師實體類（多方）
* @author ZhangCheng on 2017-07-13
*
*/
@Entity
public class Teachers {
/** 教師編號 */
@Id
@GeneratedValue(generator="tid")
@GenericGenerator(name="tid",strategy="assigned")
@Column(length=4)
private String tid;
/** 教師姓名 */
private String tname;
public Teachers(String tid, String tname) {
this.tid = tid;
this.tname = tname;
}
public Teachers() {
}
@Override
public String toString() {
return "Teachers [tid=" + tid + ", tname=" + tname + "]";
}
public String getTid() {
return tid;
}
public void setTid(String tid) {
this.tid = tid;
}
public String getTname() {
return tname;
}
public void setTname(String tname) {
this.tname = tname;
}
}
3.修改hibernate配置文件
同上
4.編寫StudentsTest類
package com.myimooc.hibernatera.manytomanyfk;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 多對多單向外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-13
*
*/
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
//@Test
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
SchemaExport export = new SchemaExport(config);
export.create(true, true);
}
}
3-12 多對多單向外鍵關聯（二）
代碼演示
1.修改StudentsTest類
package com.myimooc.hibernatera.manytomanyfk;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Before;
import org.junit.Test;
/**
* 多對多單向外鍵關聯
* 單元測試類
* @author ZhangCheng on 2017-07-13
*
*/
public class StudentsTest {
private SessionFactory sessionFactory = null;
@Before
//@Test
public void schemaExportTest(){
// 建立hibernate配置對象
Configuration config = new Configuration().configure();
// 建立服務註冊對象
ServiceRegistry ServiceRegistry = new ServiceRegistryBuilder()
.applySettings(config.getProperties()).buildServiceRegistry();
// 生成sessionFactory
sessionFactory = config.buildSessionFactory(ServiceRegistry);
SchemaExport export = new SchemaExport(config);
export.create(true, true);
}
@Test
public void addStudents(){
Session session = sessionFactory.getCurrentSession();
Transaction tx = session.beginTransaction();
// 建立教師對象
Teachers t1 = new Teachers("T001","張老師");
Teachers t2 = new Teachers("T002","李老師");
Teachers t3 = new Teachers("T003","陳老師");
Teachers t4 = new Teachers("T004","劉老師");
// 建立學生對象
Students s1 = new Students("張三","男",new Date(),"計算機");
Students s2 = new Students("李四","男",new Date(),"計算機");
Students s3 = new Students("王五","女",new Date(),"計算機");
Students s4 = new Students("趙六","女",new Date(),"計算機");
// 建立教師集合
Set<Teachers> set1 = new HashSet<Teachers>();
set1.add(t1);
set1.add(t2);
Set<Teachers> set2 = new HashSet<Teachers>();
set2.add(t3);
set2.add(t4);
Set<Teachers> set3 = new HashSet<Teachers>();
set3.add(t1);
set3.add(t3);
set3.add(t4);
Set<Teachers> set4 = new HashSet<Teachers>();
set4.add(t2);
set4.add(t3);
set4.add(t4);
// 設置學生教師
s1.setTeachers(set1);
s2.setTeachers(set2);
s3.setTeachers(set3);
s4.setTeachers(set4);
// 保存教師信息
session.save(t1);
session.save(t2);
session.save(t3);
session.save(t4);
// 保存學生信息
session.save(s1);
session.save(s2);
session.save(s3);
session.save(s4);
tx.commit();
}
}
3-13 多對多雙向外鍵關聯
多對多雙向外鍵
雙方持有對方的集合對象，其中一方設置
// 教師類
@ManyToMany(mappedBy=」teachers」)
// 學生類中添加如下註解
@ManyToMany
@JoinTable(
name=」teachers_students」,
joinColumns = {@JoinColumn(name=」sid」)},
inverseJoinColumns={@JoinColumn(name=」tid」)})
代碼演示
1.編寫Students類
// 學生持有教師的集合
@ManyToMany
@JoinTable(
name="teachers_students",
joinColumns={@JoinColumn(name="sid")},
inverseJoinColumns={@JoinColumn(name="tid")}
)
private Set<Teachers> teachers;
2.編寫Teachers類
// 教師持有學生的集合
@ManyToMany(mappedBy="teachers")
private Set<Students> students;
3.修改hibernate配置文件
同上
4.編寫StudentsTest類
同多對多單向外鍵關聯測試類
第四章：課程總結
4-1 課程總結
類級別註解
@Entity @Table @Embeddable
屬性級別註解
@Id @GeneratedValue @Column @Embedded @EmbeddedId @Transient
映射關係註解
@OneToOne：一對一單向外鍵 @OneToOne(mappedBy=」xxx」)：一對一雙向外鍵關聯 @Embeddable和@EmbeddedId：一對一單向外鍵聯合主鍵 @ManyToOne和@JoinColumn：多對一單向外鍵關聯 @OneToMany和@JoinColumn：一對多單向外鍵關聯 @ManyToOne和@OneToMany 和@JoinColumn：一對多雙向外鍵關聯 @ManyToMany和@JoinColumn：多對多單向外鍵關聯 @ManyToMany(mappedBy=」xxx」)和@JoinTable：多對多雙向外鍵關聯
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