在hibernate中，如何将一个表中的两个外键映射到另一个表中的一个主键

ER图如下所示

我创建了实体类，如下所示：

@Entity
@Table(name = "state_flows")
public class StateFlowEntity {

private int id;
private StateMachineEntity stateMachine;
private StateEntity currentState;
private StateEntity nextState;

@ManyToOne
@JoinColumn(name = "current_state", referencedColumnName = "id",
    insertable = false, updatable = false)
public StateEntity getCurrentState() {
return currentState;
}

@ManyToOne
@JoinColumn(name = "next_state", referencedColumnName = "id",
    insertable = false, updatable = false)
public StateEntity getNextState() {
return nextState;
}

@ManyToOne
@JoinColumn(name = "machine_id", referencedColumnName = "id",
    insertable = false, updatable = false)
public StateMachineEntity getStateMachine() {
return stateMachine;
}

//setters and getters

===================================================================

@Entity
@Table(name = "states")
public class StateEntity {

public enum NodeType {
EVENT
};

private int id;
private String name;
private NodeType nodeType;
private String nodeId;
private int ratio;
private int missingRatio;
private String nodeDetail;
private Set<StateFlowEntity> nextStateFlows = new HashSet<StateFlowEntity>();
private Set<StateFlowEntity> currentStateFlows = new HashSet<StateFlowEntity>();

@OneToMany(cascade = CascadeType.ALL, mappedBy = "nextState",
    targetEntity = StateEntity.class)
public Set<StateFlowEntity> getNextStateFlows() {
return nextStateFlows;
}

@OneToMany(cascade = CascadeType.ALL, mappedBy = "currentState",
    targetEntity = StateEntity.class)
public Set<StateFlowEntity> getCurrentStateFlows() {
return currentStateFlows;
}

@Column(name = "node_type", nullable = false,
    columnDefinition = "ENUM('EVENT') default 'EVENT'")
@Enumerated(EnumType.STRING)
private NodeType getNodeType() {
return nodeType;
}

//setter and getters

@Entity
@Table(name = "state_machines")
public class StateMachineEntity {

private int id;
private String name;
private String description;
private int initialState;
private int combinational;
private Set<StateFlowEntity> machineId = new HashSet<StateFlowEntity>();
private Set<InstanceEntity> instances = new HashSet<InstanceEntity>();

@OneToMany(cascade = CascadeType.ALL, mappedBy = "stateMachine")
public Set<StateFlowEntity> getMachineId() {
return machineId;
}

@OneToMany(cascade = CascadeType.ALL, mappedBy = "stateMachine")
public Set<InstanceEntity> getInstances() {
return instances;
}

//setters and getters

@实体
@表（name=“states”）
公共类国家实体{
公共枚举节点类型{
事件
};
私有int-id；
私有字符串名称；
私有节点类型节点类型；
私有字符串nodeId；
私人投资比率；
私人信息丢失率；
私有字符串nodeDetail；
private Set nextStateFlows=new HashSet（）；
私有集currentStateFlows=new HashSet（）；
@OneToMany（cascade=CascadeType.ALL，mappedBy=“nextState”，
targetEntity=StateEntity.class）
公共集getNextStateFlows（）{
返回下一个状态流；
}
@OneToMany（cascade=CascadeType.ALL，mappedBy=“currentState”，
targetEntity=StateEntity.class）
公共集getCurrentStateFlows（）{
回流；
}
@列（name=“node\u type”，null=false，
columnDefinition=“枚举（“事件”）默认值“事件”）
@枚举（EnumType.STRING）
私有节点类型getNodeType（）{
返回节点类型；
}
//二传手和接球手

======================================================================================

@Entity
@Table(name = "states")
public class StateEntity {

public enum NodeType {
EVENT
};

private int id;
private String name;
private NodeType nodeType;
private String nodeId;
private int ratio;
private int missingRatio;
private String nodeDetail;
private Set<StateFlowEntity> nextStateFlows = new HashSet<StateFlowEntity>();
private Set<StateFlowEntity> currentStateFlows = new HashSet<StateFlowEntity>();

@OneToMany(cascade = CascadeType.ALL, mappedBy = "nextState",
    targetEntity = StateEntity.class)
public Set<StateFlowEntity> getNextStateFlows() {
return nextStateFlows;
}

@OneToMany(cascade = CascadeType.ALL, mappedBy = "currentState",
    targetEntity = StateEntity.class)
public Set<StateFlowEntity> getCurrentStateFlows() {
return currentStateFlows;
}

@Column(name = "node_type", nullable = false,
    columnDefinition = "ENUM('EVENT') default 'EVENT'")
@Enumerated(EnumType.STRING)
private NodeType getNodeType() {
return nodeType;
}

//setter and getters

@Entity
@Table(name = "state_machines")
public class StateMachineEntity {

private int id;
private String name;
private String description;
private int initialState;
private int combinational;
private Set<StateFlowEntity> machineId = new HashSet<StateFlowEntity>();
private Set<InstanceEntity> instances = new HashSet<InstanceEntity>();

@OneToMany(cascade = CascadeType.ALL, mappedBy = "stateMachine")
public Set<StateFlowEntity> getMachineId() {
return machineId;
}

@OneToMany(cascade = CascadeType.ALL, mappedBy = "stateMachine")
public Set<InstanceEntity> getInstances() {
return instances;
}

//setters and getters

@实体
@表（name=“state\u machines”）
公共阶级国家机器{
私有int-id；
私有字符串名称；
私有字符串描述；
私有国家；
私有int组合；
私有集machineId=新HashSet（）；
私有集实例=新HashSet（）；
@OneToMany（cascade=CascadeType.ALL，mappedBy=“stateMachine”）
公共集getMachineId（）{
返回机器ID；
}
@OneToMany（cascade=CascadeType.ALL，mappedBy=“stateMachine”）
公共集getInstances（）{
返回实例；
}
//二传手和接球手

=============================================================

@Entity
@Table(name = "states")
public class StateEntity {

public enum NodeType {
EVENT
};

private int id;
private String name;
private NodeType nodeType;
private String nodeId;
private int ratio;
private int missingRatio;
private String nodeDetail;
private Set<StateFlowEntity> nextStateFlows = new HashSet<StateFlowEntity>();
private Set<StateFlowEntity> currentStateFlows = new HashSet<StateFlowEntity>();

@OneToMany(cascade = CascadeType.ALL, mappedBy = "nextState",
    targetEntity = StateEntity.class)
public Set<StateFlowEntity> getNextStateFlows() {
return nextStateFlows;
}

@OneToMany(cascade = CascadeType.ALL, mappedBy = "currentState",
    targetEntity = StateEntity.class)
public Set<StateFlowEntity> getCurrentStateFlows() {
return currentStateFlows;
}

@Column(name = "node_type", nullable = false,
    columnDefinition = "ENUM('EVENT') default 'EVENT'")
@Enumerated(EnumType.STRING)
private NodeType getNodeType() {
return nodeType;
}

//setter and getters

@Entity
@Table(name = "state_machines")
public class StateMachineEntity {

private int id;
private String name;
private String description;
private int initialState;
private int combinational;
private Set<StateFlowEntity> machineId = new HashSet<StateFlowEntity>();
private Set<InstanceEntity> instances = new HashSet<InstanceEntity>();

@OneToMany(cascade = CascadeType.ALL, mappedBy = "stateMachine")
public Set<StateFlowEntity> getMachineId() {
return machineId;
}

@OneToMany(cascade = CascadeType.ALL, mappedBy = "stateMachine")
public Set<InstanceEntity> getInstances() {
return instances;
}

//setters and getters

但它给了我以下的错误：

初始化数据库连接时出错。 org.hibernate.AnnotationException:mappedBy引用com.test.entity.StateEntity.currentStateFlows中的未知目标实体属性：com.test.orm.entity.StateEntity.currentState

---

我不熟悉hibernate，在那里我做错了？

就像@Naros提到的那样，targetEntity应该是“StateFlowEntity.class”，或者根本不需要指定

@OneToMany(cascade = CascadeType.ALL, mappedBy = "currentState",
    targetEntity = StateEntity.class)

由于您在代码中明确提到了“targetEntity=StateEntity.class”，它正在“StateEntity”类中查找“currentState”字段。这就是错误消息的含义

在做了这些更改之后，我能够用Spring Boot加载这些实体

@OneToMany(cascade = CascadeType.ALL, mappedBy = "nextState",
        targetEntity = StateFlowEntity.class)
private Set<StateFlowEntity> nextStateFlows = new HashSet<StateFlowEntity>();

@OneToMany(cascade = CascadeType.ALL, mappedBy = "currentState" )
private Set<StateFlowEntity> currentStateFlows = new HashSet<StateFlowEntity>();

@OneToMany（cascade=CascadeType.ALL，mappedBy=“nextState”，
targetEntity=StateFlowEntity.class）
private Set nextStateFlows=new HashSet（）；
@OneToMany（cascade=CascadeType.ALL，mappedBy=“currentState”）
私有集currentStateFlows=new HashSet（）；

是否确实要在此处使用

状态实体

上的targetEntity？集合类型

状态实体

不公开

下一状态

和

当前状态

的命名属性，因此这两个属性都可能出现此错误。谢谢，删除targetEntity可消除此错误