Database Hibernate @OneToMany 在更新父级时从列表中删除子级

我有以下实体:

团队

@Entity
@Table
public class Team {
[..]
private Set<UserTeamRole> userTeamRoles;

/**
 * @return the userTeamRoles
 */
@OneToMany(cascade = { CascadeType.ALL }, mappedBy = "team", fetch = FetchType.LAZY)
public Set<UserTeamRole> getUserTeamRoles() {
    return userTeamRoles;
}

/**
 * @param userTeamRoles
 *            the userTeamRoles to set
 */
public void setUserTeamRoles(Set<UserTeamRole> userTeamRoles) {
    this.userTeamRoles = userTeamRoles;
}

}

和

USER_团队_ROLE

@Entity
@Table(name = "user_team_role")
public class UserTeamRole {

 @ManyToOne(cascade = CascadeType.MERGE, fetch = FetchType.LAZY)
 @JoinColumn(name = "FK_TeamId")
 public Team getTeam() {
    return team;
 }
}

Now, when updating a Team entity that contains for example Team.userTeamRoles = {UTR1, UTR2} with {UTR1, UTR3}, I want UTR2 to be deleted. But the way I do it now, the old list remains the same 和 it only adds UTR3 to the list.

目前我是这样做的:

 if (!usersDualListData.getTarget().isEmpty()) {
        // the role for each user within the team will be "employee"
        team.setUserTeamRoles(new HashSet<UserTeamRole>());
        Role roleForUser = roleService
                .getRoleByName(RoleNames.ROLE_EMPLOYEE.name());
        for (User user : usersDualListData.getTarget()) {
            UserTeamRole utr = new UserTeamRole();
            utr.setUser(user);
            utr.setTeam(team);
            utr.setRole(roleForUser);
            team.getUserTeamRoles().add(utr);
        }
    }

teamService.updateTeam(team);

I thought that by doing team.setUserTeamRoles(new HashSet<UserTeamRole>()); the list would be reset 和 because of the cascades the previous list would be deleted.

如有任何帮助，我们将不胜感激.谢谢