Question

我有一个小样本应用程序，我想在其中实现hibernate级联效果，其中我有一个人模型和一个信用卡模型。一个人可以拥有一张以上的信用卡。

以下是人物模型：

import java.io.Serializable;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

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

/**
 * Represents a person entity
 *
 * @author 
 * 
 */
@Entity
@Table(name = "PERSON")
public class Person implements Serializable {

 private static final long serialVersionUID = -5527566248002296042L;


 public Person() {

 }
 public Person(String furstBame) {
     this.firstName  = furstBame;
 }

 @Id
 @Column(name = "ID")
 @GeneratedValue(strategy=GenerationType.AUTO)
 private Integer id;

 @Column(name = "FIRST_NAME")
 private String firstName;

 @Column(name = "LAST_NAME")
 private String lastName;

 @Column(name = "MONEY")
 private Double money;

@OneToMany (mappedBy="person")
private List<CreditCard> creditCards;

 public Integer getId() {
  return id;
 }

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

 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 Double getMoney() {
  return money;
 }

 public void setMoney(Double money) {
  this.money = money;
 }
public List<CreditCard> getCreditCards() {
    return creditCards;
}
public void setCreditCards(List<CreditCard> creditCards) {
    this.creditCards = creditCards;
}
}

这是信用卡型号：

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;


/**
 * Represents a credit card entity
 *
 * 
 */
@Entity
@Table(name = "CREDIT_CARD")
public class CreditCard implements Serializable {

 private static final long serialVersionUID = 5924361831551833717L;
    public CreditCard() {
        System.out.println("CreditCard");
    }
 @Id
 @Column(name = "ID")
 @GeneratedValue
 private Integer id;

 @Column(name = "TYPE")
 private String type;

 @Column(name = "NUMBER")
 private String number;

 @ManyToOne
 @JoinColumn (name="person_ID")
 private Person person;

 public Integer getId() {
  return id;
 }

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

 public String getType() {
  return type;
 }

 public void setType(String type) {
  this.type = type;
 }

 public String getNumber() {
  return number;
 }

 public void setNumber(String number) {
  this.number = number;
 }

 public Person getPerson() {
  return person;
 }

 public void setPerson(Person person) {
  this.person = person;
 }


}

请编辑代码和任何人请解释在这些情况下添加级联的实际语法。我使用的是注释，而不是XML的东西。

Answer 1

您需要使用：

@OneToMany (mappedBy="person" cascade=CascadeType.ALL)

如果您希望在删除此人时删除个人信用卡，则还需要指定：

@OneToMany (mappedBy="person" cascade=CascadeType.ALL, orphanRemoval=true)

Hibernate在一对多映射中级联

1 个答案: