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Java 如何连接几个具有扩展名的表_Java_Database_Spring_Hibernate_Persistence - Fatal编程技术网

Java 如何连接几个具有扩展名的表

Java 如何连接几个具有扩展名的表,java,database,spring,hibernate,persistence,Java,Database,Spring,Hibernate,Persistence,我有Team.class和Player.class,它们是实体,当然还有更多的字段等。我想在不改变Team.class的情况下将Player扩展到不同的玩家类型。最好的解决方案是删除球员表,使足球运动员etc表继承球员字段 问题是如何在团队中加入不同类型的球员。如果没有球员表,但有足球和手球球员表 @Entity @Table(name = "Team") public class Team { private String name; @ManyToMany(fetch =

我有Team.class和Player.class,它们是实体,当然还有更多的字段等。我想在不改变Team.class的情况下将Player扩展到不同的玩家类型。最好的解决方案是删除球员表,使足球运动员etc表继承球员字段

问题是如何在团队中加入不同类型的球员。如果没有球员表,但有足球和手球球员表

@Entity
@Table(name = "Team")
public class Team {

    private String name;

    @ManyToMany(fetch = FetchType.LAZY)
    @Cascade({org.hibernate.annotations.CascadeType.SAVE_UPDATE})
    @JoinTable(name = "TeamPlayer", joinColumns = {
            @JoinColumn(name = "team_id", nullable = false, updatable = true) },
            inverseJoinColumns = { @JoinColumn(name = "player_id",
                    nullable = false, updatable = true) })
    private List<Player> players = new ArrayList<Player>();




@Entity
@Table(name = "Player")
public class Player extends User {
@ManyToMany(fetch = FetchType.LAZY, mappedBy = "players")
@Cascade({org.hibernate.annotations.CascadeType.SAVE_UPDATE})
 private List<Team> teams = new ArrayList<Team>();
@实体
@表(name=“Team”)
公开课小组{
私有字符串名称;
@ManyToMany(fetch=FetchType.LAZY)
@级联({org.hibernate.annotations.CascadeType.SAVE_UPDATE})
@JoinTable(name=“TeamPlayer”,JointColumns={
@JoinColumn(name=“team_id”,nullable=false,updateable=true)},
inverseJoinColumns={@JoinColumn(name=“player\u id”,
nullable=false,updateable=true)})
private List players=new ArrayList();
@实体
@表(name=“Player”)
公共类播放器扩展用户{
@ManyToMany(fetch=FetchType.LAZY,mappedBy=“players”)
@级联({org.hibernate.annotations.CascadeType.SAVE_UPDATE})
私有列表团队=新的ArrayList();