引自：http://www.cnblogs.com/hongten/archive/2011/07/20/2111773.html
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2
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"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
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"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
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6
7
8
9
1 package com.b510.examples;
2
3 import java.util.HashSet;
4 import java.util.Set;
5
6 // 标准注解
7
8 import
javax.persistence.CascadeType;
9 import javax.persistence.Column;
1 package com.b510.examples;
2
3 import javax.persistence.Column;
4 import javax.persistence.Entity;
5 import javax.persistence.FetchType;
6 import
javax.persistence.GeneratedValue;
7 import javax.persistence.Id;
8 import javax.persistence.JoinColumn;
9 import javax.persistence.ManyToOne;
1
4 package com.b510.examples;
5
6 import java.util.Set;
7
8 import org.hibernate.Session;
9 import org.hibernate.SessionFactory;
1 log4j:WARN No appenders could be found for
logger (org.hibernate.cfg.annotations.Version).
2 log4j:WARN Please initialize the log4j
system properly.
3 Hibernate:
4
select
5
category0_.id as
id1_0_,
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category0_.description as
descript2_1_0_,
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category0_.name as
name1_0_
8
from
9
users.category
category0_
进入：http://www.hibernate.org
说明文档：
英文：http://docs.jboss.org/hibernate/annotations/3.5/reference/en/html_single/
中文：http://docs.jboss.org/hibernate/annotations/3.4/reference/zh_cn/html_single/
下载：hibernate annotation 3.4.0 GA
得到：hibernate-annotations.jar
hibernate-commons-annotation.jar
ejb3-persistence.jar
数据库：mysql
category表：id，name，description
id
product表：id,name ,price, description ,category_id
id
category_id
新建java project项目：
Add Hibernate Capabilities
hibernate.cfg.xml
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11
org.hibernate.dialect.MySQLDialect
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13
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jdbc:mysql://localhost:3307/users
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16 root
17 root
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19
com.mysql.jdbc.Driver
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21
22 mysqlusers
23
24 true
25 true
26 thread
27
28
29
30
31
32
利用Hibernate的逆向工程生成：
Category.java
and
Product.java
Category.java
10 import javax.persistence.Entity;
11 import javax.persistence.FetchType;
12 import javax.persistence.GeneratedValue;
13 import javax.persistence.Id;
14 import javax.persistence.OneToMany;
15 import javax.persistence.Table;
16
17 //增加的注解
18
19 import org.hibernate.annotations.GenericGenerator;
20
21 //当前的类是一个持久化类，是Category这个类。他映射了一个表category。所对应的
数据库是users
22 //这句：@Table(name = "category", catalog = "users")
可以省略
23 @Entity
24 @Table(name = "category", catalog = "users")
25
26 public class Category implements java.io.Serializable
{
27
28 private static final long
serialVersionUID = 3240281547213597385L;
29 private Integer id;
30 private String name;
31 private String description;
32 private Set products = new
HashSet(0);
33
34
35 public Category() {
36 }
37
38 public Category(String name, String
description, Set products) {
39 this.name = name;
40 this.description = description;
41 this.products = products;
42 }
43
44 // 主键 ：@Id
主键生成方式：strategy = "increment"
45 //映射表中id这个字段，不能为空，并且是唯一的
46 @GenericGenerator(name = "generator",
strategy = "increment")
47 @Id
48 @GeneratedValue(generator =
"generator")
49 @Column(name = "id", unique = true,
nullable = false)
50 public Integer getId() {
51 return this.id;
52 }
53
54 public void setId(Integer id) {
55 this.id = id;
56 }
57
58 //映射表中name这个字段 ，长度是500
59 @Column(name = "name", length =
500)
60 public String getName() {
61 return this.name;
62 }
63
64 public void setName(String name) {
65 this.name = name;
66 }
67
68 //映射表中description这个字段 ，长度是500
69 @Column(name = "description", length =
500)
70 public String getDescription() {
71 return this.description;
72 }
73
74 public void setDescription(String
description) {
75 this.description = description;
76 }
77
78 //级联操作：cascade = CascadeType.ALL
79 //延迟加载：fetch = FetchType.LAZY
80 //映射：mappedBy = "category"
81 //一对多方式
82 @OneToMany(cascade = CascadeType.ALL,
fetch = FetchType.LAZY, mappedBy = "category")
83 public Set getProducts() {
84 return this.products;
85 }
86
87 public void setProducts(Set products)
{
88 this.products = products;
89 }
90
91 }
Product.java
10 import javax.persistence.Table;
11 import org.hibernate.annotations.GenericGenerator;
12
13
14 @Entity
15 @Table(name = "product", catalog = "users")
16 public class Product implements java.io.Serializable
{
17
18 private static final long
serialVersionUID = -1546206493725028472L;
19 private Integer id;
20 private Category category;
21 private String name;
22 private String price;
23 private String descripton;
24
25
26 public Product() {
27 }
28
29 public Product(Category category, String
name, String price,
30 String descripton)
{
31 this.category = category;
32 this.name = name;
33 this.price = price;
34 this.descripton = descripton;
35 }
36
37 @GenericGenerator(name = "generator",
strategy = "increment")
38 @Id
39 @GeneratedValue(generator =
"generator")
40 @Column(name = "id", unique = true,
nullable = false)
41 public Integer getId() {
42 return this.id;
43 }
44
45 public void setId(Integer id) {
46 this.id = id;
47 }
48
49 //延迟加载：多对一方式
50 //关联信息：外键name = "category_id"
51 @ManyToOne(fetch = FetchType.LAZY)
52 @JoinColumn(name = "category_id")
53 public Category getCategory() {
54 return this.category;
55 }
56
57 public void setCategory(Category
category) {
58 this.category = category;
59 }
60
61 @Column(name = "name", length =
500)
62 public String getName() {
63 return this.name;
64 }
65
66 public void setName(String name) {
67 this.name = name;
68 }
69
70 @Column(name = "price", length =
10)
71 public String getPrice() {
72 return this.price;
73 }
74
75 public void setPrice(String price)
{
76 this.price = price;
77 }
78
79 @Column(name = "descripton", length =
500)
80 public String getDescripton() {
81 return this.descripton;
82 }
83
84 public void setDescripton(String
descripton) {
85 this.descripton = descripton;
86 }
87
88 }
测试代码：
HibernateTest.java
10 import org.hibernate.cfg.AnnotationConfiguration;
11 import org.hibernate.cfg.Configuration;
12
13
20 public class HibernateTest {
21
22 public static void main(String[] args)
{
23 HibernateTest test=new
HibernateTest();
24 test.add();
25 test.find();
26 }
27 public void add(){
28 Configuration config=new
AnnotationConfiguration();
29 config.configure();
30 SessionFactory
sessionFactory=config.buildSessionFactory();
31 Session
session=sessionFactory.getCurrentSession();
32 session.beginTransaction();
33 Category
c=(Category)session.get(Category.class, 5);
34
35 Product p=new Product();
36 p.setName("计算机科学与技术");
37 p.setPrice("123");
38
p.setDescripton("计算机科学与技术,好啊，真是红啊");
39
40 p.setCategory(c);
41 c.getProducts().add(p);
42
43 session.save(p);
44 session.getTransaction().commit();
45 }
46
47
48 public void find(){
49 Configuration config=new
AnnotationConfiguration();
50 config.configure();
51 SessionFactory
sessionFactory=config.buildSessionFactory();
52 Session
session=sessionFactory.getCurrentSession();
53 session.beginTransaction();
54 Category
c=(Category)session.get(Category.class, 5);
55
System.out.println("id: "+c.getId()+"
name:"+c.getName());
56 Set
p=c.getProducts();
57 for(Product
product:p){
58
System.out.println("id:"+product.getId()+"
name:"+product.getName()+"
description:"+product.getDescripton());
59 }
60
session.getTransaction().commit();
61 }
62 }
运行效果：
10 where
11
category0_.id=?
12 Hibernate:
13 select
14
products0_.category_id as category5_1_,
15
products0_.id as id1_,
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products0_.id as id0_0_,
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products0_.category_id as category5_0_0_,
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products0_.descripton as descripton0_0_,
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products0_.name as name0_0_,
20
products0_.price as
price0_0_
21 from
22
users.product products0_
23 where
24
products0_.category_id=?
25 Hibernate:
26 select
27
max(id)
28 from
29
product
30 Hibernate:
31
insert
32 into
33
users.product
34
(category_id, descripton, name, price,
id)
35 values
36
(?, ?, ?, ?, ?)
37 Hibernate:
38 select
39
category0_.id as id5_0_,
40
category0_.description as descript2_5_0_,
41
category0_.name as
name5_0_
42 from
43
users.category
category0_
44 where
45
category0_.id=?
46 id: 5 name:xml33
47 Hibernate:
48 select
49
products0_.category_id as category5_1_,
50
products0_.id as id1_,
51
products0_.id as id4_0_,
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products0_.category_id as category5_4_0_,
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products0_.descripton as descripton4_0_,
54
products0_.name as name4_0_,
55
products0_.price as
price4_0_
56 from
57
users.product products0_
58 where
59
products0_.category_id=?
60 id:9 name:计算机科学与技术
description:计算机科学与技术,好啊，真是红啊
分类: Hibernate
标签: java, hibernate, annotation, 注解
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