hibernate的一对一映射-主键映射-单向-mysql数据库

谁借莪１个温暖的怀抱￠ 2022-09-24 02:29 127阅读 0赞

import java.io.Serializable;
    
    import javax.persistence.CascadeType;
    import javax.persistence.Column;
    import javax.persistence.Entity;
    import javax.persistence.FetchType;
    import javax.persistence.Id;
    import javax.persistence.OneToOne;
    import javax.persistence.PrimaryKeyJoinColumn;
    import javax.persistence.Table;
    /**
     * 1对1 单向
     * 主键关联
     * @author WuJieJecket
     * alt +上/下 交换两行代码
     * ctrl+alt +上/下复制一行代码
     */
    @Entity(name="DNFCLASS")
    @Table(name="DNFCLASS")
    @SuppressWarnings("serial")
    public class Dnfclass implements Serializable {
    	private String dclassname;
    	private Dnfstudent dfs;
    	/**
    	 * @return the dclassname
    	 */
    	@Id
    	@Column(name="DCLASSNAME")
    	public String getDclassname() {
    		return dclassname;
    	}
    	/**
    	 * @param dclassname the dclassname to set
    	 */
    	public void setDclassname(String dclassname) {
    		this.dclassname = dclassname;
    	}
    	/**
    	 * @return the dfs
    	 */
    	@OneToOne(cascade=CascadeType.ALL,fetch=FetchType.LAZY)
    	@PrimaryKeyJoinColumn//主键依赖，就没有外键这么一说了
    	public Dnfstudent getDfs() {
    		return dfs;
    	}
    	/**
    	 * @param dfs the dfs to set
    	 */
    	public void setDfs(Dnfstudent dfs) {
    		this.dfs = dfs;
    	}
    	
    	
    	
    }

import java.io.Serializable;
    
    import javax.persistence.Column;
    import javax.persistence.Entity;
    import javax.persistence.Id;
    import javax.persistence.Table;
    
    @Entity(name="DNFSTUDENT")
    @Table(name="DNFSTUDENT")
    @SuppressWarnings("serial")
    public class Dnfstudent implements Serializable {
    	private String dstudentname;
    
    	/**
    	 * @return the dstudentname
    	 */
    	@Id
    	@Column(name="DSTUDENTNAME")
    	public String getDstudentname() {
    		return dstudentname;
    	}
    
    	/**
    	 * @param dstudentname the dstudentname to set
    	 */
    	public void setDstudentname(String dstudentname) {
    		this.dstudentname = dstudentname;
    	}
    	
    	
    
    }

配置文件

<?xml version="1.0" encoding="UTF-8"?>  
<!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="connection.driver\_class">  
com.mysql.jdbc.Driver  
</property>  
  
<property name="connection.url">  
jdbc:mysql://localhost:3306/test  
</property>  
  
<property name="connection.username">用户名</property>  
  
<property name="connection.password">密码</property>  
  
<property name="dialect">  
org.hibernate.dialect.MySQLDialect  
</property>  
  
<property name="show\_sql">true</property>  
<property name="format\_sql">true</property>  
<property name="hbm2ddl.auto">update</property>  
<mapping class="hibernate.dnfonetoone.Dnfclass" />  
<mapping class="hibernate.dnfonetoone.Dnfstudent" />  
  
  
  
  
</session-factory>  
  
  
</hibernate-configuration>

测试方法

/*
    	 * 1对1 单向 主键关联
    	 */
    	@Test
    	public void testnfOnetoone(){
    		
    		
    		HIbernateUtil hbu=new HIbernateUtil();
    		Session s=hbu.getSession();
    		s.beginTransaction();
    		
    		Dnfstudent dst=new Dnfstudent();
    		dst.setDstudentname("小明"+hbu.returnid());
    		
    		Dnfclass dc=new Dnfclass();
    		dc.setDclassname("语文"+hbu.returnid());
    		dc.setDfs(dst);
    		
    		s.save(dc);
    		
    		s.getTransaction().commit();
    		s.close();
    	}