hibernate xml 和 annotation 对比（一）

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今天研究了一天一对多多对一

先上 xml

package org.hibernate.tutorial.domain;public class Address {private int addid;private String addressname;private User user;public int getAddid() {return addid;}public void setAddid(int addid) {this.addid = addid;}public String getAddressname() {return addressname;}public void setAddressname(String addressname) {this.addressname = addressname;}public User getUser() {return user;}public void setUser(User user) {this.user = user;}}

package org.hibernate.tutorial.domain;import java.util.List;import java.util.Set;public class User {private int userid;private String username;public User() {}private List<Address> addresss;public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}public List<Address> getAddresss() {return addresss;}public void setAddresss(List<Address> addresss) {this.addresss = addresss;}public int getUserid() {return userid;}public void setUserid(int userid) {this.userid = userid;}}

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="org.hibernate.tutorial.domain">

<class name="User" table="user">
<id name="userid" column="userid">
<generator class="native" />
</id>
<property name="username" column="username" />

<list name="addresss" cascade="all" > 这里加上 inverse = true 后打印结果为二

<key column="userid" />

<index column = "addid"></index>

<one-to-many class="Address" />

</list>
</class>

</hibernate-mapping>

User user = (User) session.load(User.class,1);
session.delete(user);

打印结果：

Hibernate: select user0_.userid as userid1_2_0_, user0_.username as username2_2_0_ from user user0_ where user0_.userid=?
Hibernate: select addresss0_.userid as userid3_2_0_, addresss0_.addid as addid1_1_0_, addresss0_.addid as addid1_0_, addresss0_.addid as addid1_1_1_, addresss0_.addressname as addressn2_1_1_, addresss0_.userid as userid3_1_1_ from address addresss0_ where addresss0_.userid=?
Hibernate: update address set userid=null, addid=null where userid=?

结果二

Hibernate: select user0_.userid as userid1_2_0_, user0_.username as username2_2_0_ from user user0_ where user0_.userid=?
Hibernate: select addresss0_.userid as userid3_2_0_, addresss0_.addid as addid1_1_0_, addresss0_.addid as addid1_0_, addresss0_.addid as addid1_1_1_, addresss0_.addressname as addressn2_1_1_, addresss0_.userid as userid3_1_1_ from address addresss0_ where addresss0_.userid=?
Hibernate: delete from address where addid=?
Hibernate: delete from user where userid=?

注解

@Entity
@Table(name="productimg")
public class Proudctimg {
@Id
@Column(name="productimgid")
@GeneratedValue(strategy=GenerationType.IDENTITY)
private Integer productimgid;

@ManyToOne(targetEntity=Proudcts.class,fetch=FetchType.EAGER,cascade=CascadeType.ALL)
// @JoinColumn(name="productid",insertable=false,unique=false)
// @Cascade(CascadeType.ALL)
@JoinColumn(name="productid", referencedColumnName="productid",nullable=false)
private Proudcts proudcts;

。。。。。。

package com.cn.hanbo.entity;

import java.util.Date;
import java.util.List;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import javax.persistence.Table;

import org.codehaus.jackson.map.annotate.JsonSerialize;
@Entity
@Table(name="products")
@JsonSerialize(include=JsonSerialize.Inclusion.NON_NULL)
public class Proudcts {
@Id
@Column(name="productid")
@GeneratedValue(strategy=GenerationType.IDENTITY)
private Integer productid;

private String productname;

private Integer tagid;

private String productdesc;

private Date newaddtime;

private Integer newage;

private Double price;

private Integer looknumber;

private Integer leavemsgid;

private Integer userid;

@OneToMany(targetEntity=Proudctimg.class,fetch=FetchType.EAGER,cascade=CascadeType.ALL,orphanRemoval=true)
// @Cascade(CascadeType.ALL)
//@Fetch(FetchMode.JOIN)
// @JoinColumn(name="productid",referencedColumnName="productid")
@JoinColumn(name="productid")
private List<Proudctimg> proudctimglist;


public List<Proudctimg> getProudctimglist() {
return proudctimglist;
}

public void setProudctimglist(List<Proudctimg> proudctimglist) {
this.proudctimglist = proudctimglist;
}

public Integer getProductid() {
return productid;
}

public void setProductid(Integer productid) {
this.productid = productid;
}

public String getProductname() {
return productname;
}

public void setProductname(String productname) {
this.productname = productname;
}

public Integer getTagid() {
return tagid;
}

public void setTagid(Integer tagid) {
this.tagid = tagid;
}

public String getProductdesc() {
return productdesc;
}

public void setProductdesc(String productdesc) {
this.productdesc = productdesc;
}



public Date getNewaddtime() {
return newaddtime;
}

public void setNewaddtime(Date newaddtime) {
this.newaddtime = newaddtime;
}

public Integer getNewage() {
return newage;
}

public void setNewage(Integer newage) {
this.newage = newage;
}

public Double getPrice() {
return price;
}

public void setPrice(Double price) {
this.price = price;
}

public Integer getLooknumber() {
return looknumber;
}

public void setLooknumber(Integer looknumber) {
this.looknumber = looknumber;
}

public Integer getLeavemsgid() {
return leavemsgid;
}

public void setLeavemsgid(Integer leavemsgid) {
this.leavemsgid = leavemsgid;
}

public Integer getUserid() {
return userid;
}

public void setUserid(Integer userid) {
this.userid = userid;
}
}

要明白hibernate 删除在持久状态，如果在瞬时态配了关联会把关联字段的外键id 制空又不删除这条记录

hibernate还有很多底层不明不白，加油才行

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