Hibernate 学习笔记( 三)-- 复合主键-蒲公英云

关于如何配置请参看:Hibernate 学习笔记(一)—用MyEclipse 6.5+MySQL 5.0的环境跑起来准备:建表

用MySQL在名为STMS数据库中建表personx

src/org.lxh.hibernate2.Personx.java

1 package org.lxh.hibernate2;
2
3 /** */ /**
4 * @author ∪∩BUG E-mail: tidelgl@163.com
5 * @version Aug 31, 2008 951 AM @ POJO类
6 */
7
8 // 实现复合主键应满足的要求：１.本类必须实现Serializable 接口
9 public class Personx implements java.io.Serializable {
10
11 private PersonxId id;
12 private int age;
13
14 public Personx() {
15 }
16
17 public PersonxId getId() {
18 return this .id;
19 }
20
21 public void setId(PersonxId id) {
22 this .id = id;
23 }
24
25 public int getAge() {
26 return age;
27 }
28
29 public void setAge( int age) {
30 this .age = age;
31 }
32 }

通过Hibernate反向工程建立personx表与Personx类的映射

首先调出DB Browser视图(Windows—view show—other—MyEclipse datebase—DB Browser)—展开MySQL_localhost至表person—右键表personx—Hibernate Reverse Engineering

src/org.lxh.hibernate2.PersonxId.java

1 package org.lxh.hibernate2;
2
3 import org.apache.commons.lang.builder.EqualsBuilder;
4 import org.apache.commons.lang.builder.HashCodeBuilder;
5 import org.lxh.hibernate1.Personx;
6
7 /** */ /**
8 * @author ∪∩BUG E-mail: tidelgl@163.com
9 * @version Aug 31, 2008 951 AM @ 复合主键类
10 */
11 // 实现复合主键应满足的要求：
12 // １.本类必须实现 Serializable 接口
13 // 2.复写equals(比较对象)和hashCode(取得Hash编码)方法(可用commons-lang-2.4.jar来复写,
14 // 下载: http://apache.mirror.phpchina.com/commons/lang/binaries/commons-lang-2.4-bin.zip )
15 public class PersonxId implements java.io.Serializable {
16
17 // Fields
18
19 private String name;
20 private String phone;
21
22 // Constructors
23
24 /** */ /** default constructor */
25 public PersonxId() {
26 }
27
28 /** */ /** full constructor */
29 public PersonxId(String name, String phone) {
30 this .name = name;
31 this .phone = phone;
32 }
33
34 // Property accessors
35
36 public String getName() {
37 return this .name;
38 }
39
40 public void setName(String name) {
41 this .name = name;
42 }
43
44 public String getPhone() {
45 return this .phone;
46 }
47
48 public void setPhone(String phone) {
49 this .phone = phone;
50 }
51
52 // 修改复写equals的方法
53 public boolean equals(Object obj) {
54 if ( this == obj) {
55 return true ;
56 }
57
58 // 如果不是Personx的实例
59 if ( ! (obj instanceof Personx)) {
60 return false ;
61 }
62 PersonxId p = (PersonxId) obj;
63 return new EqualsBuilder().append( this .name, p.getName()).append(
64 this .phone, p.getPhone()).isEquals();
65 }
66
67 // 修改复写hashCode的方法
68 public int hashCode() {
69 return new HashCodeBuilder().append( this .name).append(
70 this .phone).toHashCode();
71 }
72
73 }

src/org.lxh.hibernate2.PersonxOperate.java

1 package org.lxh.hibernate2;
2
3
4 import org.hibernate.Session;
5 import org.hibernate.cfg.Configuration;
6
7 /** */ /**
8 * @author ∪∩BUG E-mail: tidelgl@163.com
9 * @version Aug 31, 2008 951 AM
10 * @ 具体操作Hibernate的类
11 */
12 public class PersonxOperate {
13 // 在 Hibernate中所有的操作都是通过Session来完成
14 private Session session;
15
16 // Session 是一个接口,必须实例化
17 // 在构造方法中实例实化Session对象
18 public PersonxOperate() {
19 // 找到Hibernae配置文件,从全局文件中取出SessionFactory,从sessionFactory中取出一个session
20 this .session = new Configuration().configure().buildSessionFactory()
21 .openSession();
22 }
23
24 // 所有的操作都是通过Session进行
25 // (1) 增加操作
26 public void insert(Personx p) {
27 // 将数据存放到数据库中
28 this .session.save(p);
29
30 // 事务提交
31 this .session.beginTransaction().commit();
32 }
33 }
34

src/org.lxh.hibernate2.Test.java

1 package org.lxh.hibernate2;
2
3
4
5 /** */ /**
6 * @author ∪∩BUG E-mail: tidelgl@163.com
7 * @version Aug 31, 2008 916 AM
8 * @测试类
9 */
10 public class Test {
11
12 /** */ /**
13 * @param args
14 */
15 public static void main(String[] args) {
16 Personx p = new Personx();
17 PersonxId pk = new PersonxId();
18
19 // name,phone 在表中是主键当插入值为空时将无法插入
20 // p.setAge(4);
21 // p.setName(“Hibernate”);
22 // p.setPhone(“123456”);
23
24 p.setAge( 2 );
25 pk.setName( “ MySQL “ );
26 pk.setPhone( “ 87654 “ );
27 p.setId(pk);
28 PersonxOperate po = new PersonxOperate();
29 po.insert(p);
30 }
31
32 }
33

src/org.lxh.hibernate2.Personx.hbm.xml

1 xml version=”1.0” encoding=”utf-8” ?>
2 DOCTYPE hibernate-mapping PUBLIC “-//Hibernate/Hibernate Mapping DTD 3.0//EN”
3 “http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd“ >
4
7 < hibernate-mapping >
8 < class name =”org.lxh.hibernate2.Personx” table =”personx”
9 catalog =”stms” >
10
14 < composite-id name =”id” class =”org.lxh.hibernate2.PersonxId” >
15 < key-property name =”name” type =”java.lang.String” >
16 < column name =”name” length =”100” />
17 key-property >
18 < key-property name =”phone” type =”java.lang.String” >
19 < column name =”phone” length =”50” />
20 key-property >
21 composite-id >
22 < property name =”age” type =”java.lang.Integer” >
23 < column name =”age” />
24 property >
25 class >
26 hibernate-mapping >
27

src/hibernate.cfg.xml

1 xml version=’1.0’ encoding=’UTF-8’ ?>
2 DOCTYPE hibernate-configuration PUBLIC
3 “-//Hibernate/Hibernate Configuration DTD 3.0//EN”
4 “http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd“ >
5
6
7 < hibernate-configuration >
8
9 < session-factory >
10 < property name =”connection.username” > root property >
11 < property name =”connection.url” >
12 jdbc//localhost:3306/STMS
13 property >
14 < property name =”dialect” >
15 org.hibernate.dialect.MySQLDialect
16 property >
17 < property name =”myeclipse.connection.profile” >
18 MySql_localhost
19 property >
20 < property name =”connection.password” > root property >
21 < property name =”connection.driver_class” >
22 com.mysql.jdbc.Driver
23 property >
24 < property name =”show_sql” > true property >
25
26
27 < mapping resource =”org/lxh/hibernate2/Personx.hbm.xml” />
28
29 session-factory >
30
31 hibernate-configuration >