第十章 基于Annotation的关系映射 一对一

如果下面部分内容有不明白的可以查找：

基于Annotation的关系映射 前期准备:http://blog.csdn.net/p_3er/article/details/9061911

基于映射文件共享主键方式实现一对一：http://blog.csdn.net/p_3er/article/details/9004419

基于映射文件唯一外键式实现一对一：http://blog.csdn.net/p_3er/article/details/9004471

1、共享主键方式:

Person:

@Entity@Table(name = "person", catalog = "hibernate")public class Person implements java.io.Serializable {private Integer id;private String name;private IdCard idCard;public Person() {}@Id@GeneratedValue@Column(name = "id", unique = true, nullable = false)public Integer getId() {return this.id;}public void setId(Integer id) {this.id = id;}@Column(name = "name", nullable = false, length = 45)public String getName() {return this.name;}public void setName(String name) {this.name = name;}@OneToOne(cascade = CascadeType.ALL)@PrimaryKeyJoinColumn // 这个注解只能写在主(生成ID)的一端,指向从表public IdCard getIdCard() {return idCard;}public void setIdCard(IdCard idCard) {this.idCard = idCard;}}

IdCard:

@Entity@Table(name = "id_card", catalog = "hibernate")public class IdCard implements java.io.Serializable {private Integer id;private Person person;private String cardNo;public IdCard() {}@Id@GenericGenerator(name = "abc", strategy = "foreign", parameters = { @Parameter(name = "property", value = "person") })@GeneratedValue(generator = "abc")@Column(name = "id", unique = true, nullable = false)/*      与映射文件相比较：         <id name="id" type="java.lang.Integer"><column name="id" /><generator class="foreign"><param name="property">person</param></generator></id>*/public Integer getId() {return this.id;}public void setId(Integer id) {this.id = id;}@OneToOne(cascade = CascadeType.ALL)@JoinColumn(name = "id", unique = true, nullable = false, insertable = false, updatable = false)public Person getPerson() {return this.person;}public void setPerson(Person person) {this.person = person;}@Column(name = "card_no", nullable = false, length = 45)public String getCardNo() {return this.cardNo;}public void setCardNo(String cardNo) {this.cardNo = cardNo;}}

测试与使用和基于映射文件基本一样：http://blog.csdn.net/p_3er/article/details/9004419

2、唯一外键方式

Person:

@Entity@Table(name = "person", catalog = "hibernate")public class Person implements java.io.Serializable {private Integer id;private String name;private IdCard idCard;public Person() {}@Id@GeneratedValue@Column(name = "id", unique = true, nullable = false)public Integer getId() {return this.id;}public void setId(Integer id) {this.id = id;}@Column(name = "name", nullable = false, length = 45)public String getName() {return this.name;}public void setName(String name) {this.name = name;}@OneToOne(cascade = CascadeType.ALL,mappedBy="person")     //<one-to-one name="idCard" property-ref="person"/>  与之前的映射文件比较    //当指定person中的mappedBy后,关系只能被idcard来主动维护public IdCard getIdCard() {return idCard;}public void setIdCard(IdCard idCard) {this.idCard = idCard;}}

IdCard:

@Entity@Table(name = "id_card", catalog = "hibernate")public class IdCard implements java.io.Serializable {private Integer id;private Person person;private String cardNo;public IdCard() {}@Id@GeneratedValue@Column(name = "id", unique = true, nullable = false)public Integer getId() {return this.id;}public void setId(Integer id) {this.id = id;}@OneToOne(cascade = CascadeType.ALL)@JoinColumn(name = "person_id", unique = true)/*  比较：<many-to-one name="person" column="person_id" unique="true" />  */public Person getPerson() {return this.person;}public void setPerson(Person person) {this.person = person;}@Column(name = "card_no", nullable = false, length = 45)public String getCardNo() {return this.cardNo;}public void setCardNo(String cardNo) {this.cardNo = cardNo;}}

测试与使用和基于映射文件基本一样：http://blog.csdn.net/p_3er/article/details/9004471