JPA 一对多单向 映射至Mysql的问题

[matrix1984]

角色Role与权限Authority，我设计成一对多单向关联，数据库mysql：

//Role.java：

@Entity
public class Role implements Serializable {
	private Integer roleid;
	private String rolename;
	private String description;
	private Set<Authority> auths = new HashSet<Authority>();
	
	@Column
	public String getDescription() {
		return description;
	}
	public void setDescription(String description) {
		this.description = description;
	}
	@Id
    @GeneratedValue
	public Integer getRoleid() {
		return roleid;
	}
	public void setRoleid(Integer roleid) {
		this.roleid = roleid;
	}
	@Column
	public String getRolename() {
		return rolename;
	}
	public void setRolename(String rolename) {
		this.rolename = rolename;
	}
        //一对多单向关联
	@OneToMany(cascade = CascadeType.REFRESH, fetch=FetchType.EAGER)
    @JoinTable(name = "role_auth", joinColumns = @JoinColumn(name = "roleid"), 
    		inverseJoinColumns = @JoinColumn(name = "authorityid"))
	public Set<Authority> getAuths() {
		return auths;
	}
	public void setAuths(Set<Authority> auths) {
		this.auths = auths;
	}
	
	// 添加权限
	public void addAuth(Authority auth) {
		this.auths.add(auth);
	}
	
	@Override 
    public int hashCode() {
        ...
    }
    
    @Override
    public boolean equals(Object obj) {
        ...
    }
}

//Authority.java：

@Entity
public class Authority implements Serializable {
	private Integer authorityid;
	// 范围
	private Range range;
	// 动作
	private Action action;
	
	public Authority() {}
	
	public Authority(Range range, Action action) {
		this.range = range;
		this.action = action;
	}
	
	@ManyToOne
	@JoinColumn(name="actionid", 
			referencedColumnName="actionid")
	public Action getAction() {
		return action;
	}
	public void setAction(Action action) {
		this.action = action;
	}
	@Id
    @GeneratedValue
	public Integer getAuthorityid() {
		return authorityid;
	}
	public void setAuthorityid(Integer authorityid) {
		this.authorityid = authorityid;
	}
	@ManyToOne
	@JoinColumn(name="rangeid", 
			referencedColumnName="rangeid")
	public Range getRange() {
		return range;
	}
	public void setRange(Range range) {
		this.range = range;
	}
	
	@Override 
    public int hashCode() {
        ...
    }
    
    @Override
    public boolean equals(Object obj) {
        ...
    }
	
}

生成的中间表为role_auth，查看建表语句：

mysql> show create table role_auth;

| Table     | Create Table

| role_auth | CREATE TABLE `role_auth` (
  `roleid` int(11) NOT NULL,
  `authorityid` int(11) NOT NULL,
  PRIMARY KEY  (`roleid`,`authorityid`),
  UNIQUE KEY `authorityid` (`authorityid`), //这里roleid被定义成唯一性？！
  KEY `FK13FEEFD183497181` (`roleid`),
  KEY `FK13FEEFD1270B3A27` (`authorityid`),
  CONSTRAINT `FK13FEEFD1270B3A27` FOREIGN KEY (`authorityid`) REFERENCES `author
ity` (`authorityid`),
  CONSTRAINT `FK13FEEFD183497181` FOREIGN KEY (`roleid`) REFERENCES `role` (`rol
eid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 |

1 row in set (0.00 sec)

如上，roleid具有唯一性，这样我在插入角色时就会出现类似“Duplicate entry '2' for key 2”的错误。
该怎么改呢？？

[matrix1984]

没人吗？自己顶下咯。