我無法運行我的 Spring Boot 應用程序，因為 JPA 存在問題。但我無法找到問題并解決它。我搜索了幾個堆棧溢出主題的解決方案，但沒有一個解決方案對我有幫助。我定義了以下模型：package xyz.blackmonster.window.models;import java.util.List;import javax.persistence.CascadeType;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.FetchType;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.OneToMany;import javax.persistence.OneToOne;import org.hibernate.annotations.GenericGenerator;/** * Window order */@Entitypublic class Order {    @Id    @GeneratedValue(generator = "system-uuid")    @GenericGenerator(name = "system-uuid", strategy = "uuid2")    private String uuid;    @OneToMany(fetch = FetchType.EAGER, mappedBy = "order", cascade = CascadeType.ALL)    private List<Window> windows;    @OneToOne(fetch = FetchType.EAGER, mappedBy = "order", cascade = CascadeType.ALL)    private Service service;    @OneToOne(fetch = FetchType.EAGER, mappedBy = "order", cascade = CascadeType.ALL)    private Cost cost;    @Column(name = "email")    private String email;    public String getUuid() {        return uuid;    }    public void setUuid(String uuid) {        this.uuid = uuid;    }    public List<Window> getWindows() {        return windows;    }    public void setWindows(List<Window> windows) {        this.windows = windows;    }    public Service getService() {        return service;    }    public void setService(Service service) {        this.service = service;    }    public Cost getCost() {        return cost;    }    public void setCost(Cost cost) {        this.cost = cost;    }    public String getEmail() {        return email;    }    public void setEmail(String email) {        this.email = email;    }}如您所見，實體使用了正確的導入 (javax.persistence.Entity)。我指出這一點，因為這是我遇到的解決方案之一。