方案1：

    1.1、在多的一方的類上加上@ToString()註解，重寫toString方法

    1.2、在程式碼中獲取一的時候主動呼叫多的toString()方法：

uopUser.getUserChannelRelationList().toString();

方案2：

    2.1、在程式碼中主動get多的一方的唯一主鍵：uopUser.getUserChannelRelationList().get[0].getId();

1、一對多的類

import lombok.*;

import javax.persistence.*;
import java.util.List;

@ToString()
@Entity
@Getter
@Setter
@Builder
@NoArgsConstructor
@AllArgsConstructor
@Table(name = "uop_user")
public class UopUser {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    private String userName;

    /**
     * 渠道
     */
    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY,mappedBy = "uopUser")
    private List<UserChannelRelation> userChannelRelationList;

    /**
     * 工業分類
     */
    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY,mappedBy = "uopUser")
    private List<UserCategoryRelation> userCategoryRelationList;

    /**
     *  分部
     */
    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY,mappedBy = "uopUser")
    private List<UserERPOrganizationFBRelation> userERPOrganizationFBRelationList;

    /**
     *  經營部門
     */
    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY,mappedBy = "uopUser")
    private List<UserERPOrganizationJYRelation> userERPOrganizationJYRelationList;


}
 

2、多的一方

import com.alibaba.fastjson.annotation.JSONType;
import com.efivestar.weaf.security.domain.ManageUser;
import com.fasterxml.jackson.annotation.JsonBackReference;
import com.fasterxml.jackson.annotation.JsonIgnore;
import lombok.*;
import org.springframework.validation.annotation.Validated;

import javax.persistence.*;
import java.util.Date;

@ToString(exclude = "uopUser")
@JSONType(ignores = "uopUser")
@Entity
@Getter
@Setter
@Builder
@NoArgsConstructor
@AllArgsConstructor
@Table(name = "user_channel_relation")
public class UserChannelRelation {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    /**
     * 使用者
     */
    @JsonIgnore
//    @JsonBackReference
    @ManyToOne
    @JoinColumn(name = "uop_user_id")
    private UopUser uopUser;

    /**
     * 渠道
     */
    @JsonIgnore
    @OneToOne(fetch = FetchType.LAZY)
    private Channel channel;

    /**
     * 可選狀態
     */
    @Column(nullable = true)
    @Builder.Default
    private boolean checkFlag = false;

    /**
     * 修改時間
     */
    @Column(name = "update_time")
    private Date updateTime;
}