hibernate annotation个人学习笔记之 @OneToOne单向关联

hibernate annotation个人学习笔记之 @OneToOne单向关联

package  com.e104cn.pda.data.anno;

import  java.io.Serializable;
import  java.util.Date;

import  javax.persistence.CascadeType;
import  javax.persistence.Entity;
import  javax.persistence.GeneratedValue;
import  javax.persistence.GenerationType;
import  javax.persistence.Id;
import  javax.persistence.JoinColumn;
import  javax.persistence.OneToOne;
import  javax.persistence.Table;
import  javax.persistence.Temporal;
import  javax.persistence.TemporalType;

import  org.hibernate.annotations.Cache;
import  org.hibernate.annotations.CacheConcurrencyStrategy;

/** */ /**
 *  <p>@Description:</p>
 *  <p>@Company:    104人力银行</p>
 *  <p>@CreateDate: 2008-5-19</p>
 *      @author :    locey.zhang 
 *        @version :   1.0     
  */
@SuppressWarnings( " serial " )
@Entity
@Table(name  =   " AUTHOR " )
@Cache(usage  =  CacheConcurrencyStrategy.READ_WRITE)
public   class  Author  implements  Serializable {

     private   static   final   long  serialVersionUID  =   7131973910486229579L ;
    
     private   int  id;
    
     private  String firstName;
    
     private  String lastName;
    
     private   boolean  male;
    
     private  Date birthday;

     private  Book book;

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
     public   int  getId()  {
         return  id;
    }

     public   void  setId( int  oid)  {
         this .id  =  oid;
    }

     public  String getFirstName()  {
         return  firstName;
    }

     public   void  setFirstName(String firstName)  {
         this .firstName  =  firstName;
    }

     public  String getLastName()  {
         return  lastName;
    }

     public   void  setLastName(String lastName)  {
         this .lastName  =  lastName;
    }

     public   boolean  isMale()  {
         return  male;
    }

     public   void  setMale( boolean  male)  {
         this .male  =  male;
    }

    @Temporal(value = TemporalType.TIMESTAMP)
     public  Date getBirthday()  {
         return  birthday;
    }

     public   void  setBirthday(Date birthday)  {
         this .birthday  =  birthday;
    }

    @OneToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = " book_oid " )
     public  Book getBook()  {
         return  book;
    }

public   void  setBook(Book book)  {
         this .book  =  book;
    }
      
}

Book.java

package  com.e104cn.pda.data.anno;

import  java.io.Serializable;
import  java.util.Date;

import  javax.persistence.Entity;
import  javax.persistence.GeneratedValue;
import  javax.persistence.GenerationType;
import  javax.persistence.Id;
import  javax.persistence.Table;
import  javax.persistence.Temporal;
import  javax.persistence.TemporalType;

import  org.hibernate.annotations.Cache;
import  org.hibernate.annotations.CacheConcurrencyStrategy;

/** */ /**
 *  <p>@Description:</p>
 *  <p>@Company:    104人力银行</p>
 *  <p>@CreateDate: 2008-5-19</p>
 *     @author:    locey.zhang 
 *       @version:   1.0     
 */
@SuppressWarnings( " serial " )
@Entity
@Table(name  =   " BOOK " )
@Cache(usage  =  CacheConcurrencyStrategy.READ_WRITE)
public   class  Book  implements  Serializable {

    private static final long serialVersionUID = -2700610405985954588L;
    
    private int oid;
    
    private String name;
    
    private String description;
    
    private Date publish;
    
    @Id
    @GeneratedValue(strategy=GenerationType.SEQUENCE)
    public int getOid() {
        return oid;
    }

    public void setOid(int oid) {
        this.oid = oid;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    @Temporal(value=TemporalType.TIMESTAMP)
    public Date getPublish() {
        return publish;
    }

    public void setPublish(Date publish) {
        this.publish = publish;
    }  
    
}

@JoinColumn注释优点与缺点
     1、优点  @Id可以使用主键生成策略 oracle为例@GeneratedValue(strategy=GenerationType.SEQUENCE)
     2、缺点 AUTHOR表中会成额外的数据列(字段BOOK_OID)
@PrimaryKeyJoinColumn与@JoinColumn相反
     1、优点  AUTHOR表中不会生成额外的数据列
     2、缺点 不可以使用主键生成策略