hibernate多对一单向关联

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多对一(many to one)单向关联映射
多对一的数据库设计原则:在多的那端加外键
//注意在创建实体类属性时应尽量避免与SQL语句中的关键字重名.
用户和组这里从用户看多个用户只能对应一个组
只需在多的一端加@ManyToOne

@Entity@Table(name = "t_user")public class User { private int id; private String name; private Group group; @ManyToOne @JoinColumn(name="groupId")//设置外键的名称 public Group getGroup() {  return group; } public void setGroup(Group group) {  this.group = group; } @Id @GeneratedValue(strategy = GenerationType.AUTO) public int getId() {  return id; } public void setId(int id) {  this.id = id; } public String getName() {  return name; } public void setName(String name) {  this.name = name; }}

@Entity@Table(name = "t_group")public class Group { private int id; private String name; @Id @GeneratedValue(strategy = GenerationType.AUTO) public int getId() {  return id; } public void setId(int id) {  this.id = id; } public String getName() {  return name; } public void setName(String name) {  this.name = name; }}