org.hibernate.HibernateException: 集合被驱逐

Question

程序员实体

import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;

import lombok.Data;
import lombok.Getter;
import lombok.Setter;

@Entity
@Getter
@Setter
@Data

public class Programmer {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    private String name;
    private int salary;
    @ManyToMany(cascade = CascadeType.ALL,fetch = FetchType.EAGER)
    @JoinTable(name = "programmers_projects", 
    joinColumns = @JoinColumn(name = "programmer_id", referencedColumnName = "id"), 
    inverseJoinColumns = @JoinColumn(name = "project_id", referencedColumnName = "id"))
    private Set<Project> projects;
    @Override
    public String toString() {
        return "Programmer [id=" + id + ", name=" + name + ", salary=" + salary + "]";
    }
}

项目实体

import java.util.Set;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToMany;

import lombok.Data;
import lombok.Getter;
import lombok.Setter;


@Entity
@Getter
@Setter
@Data

public class Project {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    private String name;
    
    @ManyToMany(mappedBy = "projects")
    private Set<Programmer> programmers;
    @Override
    public String toString() {
        return "Project [id=" + id + ", name=" + name + "]";
    }

}

存储库

import org.springframework.data.repository.CrudRepository;

import com.springdata.associations.onetomay.entities.Programmer;

public interface ProgrammerRepo extends CrudRepository<Programmer, Integer> {

}

Junit 测试

    @Test
    
    public void loadMtoMProgrammers() {
        Programmer programmer = repos.findById(1).get();
        System.out.println(programmer);
        System.out.println(programmer.getProjects());
        
        } 

获取错误

Hibernate：选择programmer0_.id as id1_2_0_，programmer0_.name as name2_2_0_，programmer0_.salary assalary3_2_0_，projects1_.programmer_id as programm1_3_1_，project2_.id as project_2_3_1_，project2_.id as id1_2_3_1_，project2_.id as id1_2_2_2_0_outer Programmers_projects projects1_ onprogrammer0_.id=projects1_.programmer_id 左外加入 Project project2_ on projects1_.project_id=project2_.id whereprogrammer0_.id=? Hibernate：选择programmer0_.project_id as project_2_3_0_，programmer0_.programmer_id as programm1_3_0_，programmer1_.id as id1_2_1_，programmer1_.name as name2_2_1_，programmer1_.salary assalary3_2_1_ fromprogrammers_projectsprogrammer1_programmer1_programmer1_programmer=programmer1_programmer_interval project_id=? 2021-08-01 10:19:41.885 INFO 7828 --- [main] oheinternal.DefaultLoadEventListener：HHH000327：执行加载命令时出错

org.hibernate.HibernateException：集合在 org.hibernate.event.internal.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:43) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final] 被驱逐.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:99) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final] 在 org.hibernate.internal.SessionImpl.initializeCollection( SessionImpl.java:2163) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final] 在 org.hibernate.collection.internal.AbstractPersistentCollection$4.doWork(AbstractPersistentCollection.java:589) ~[hibernate- core-5.4.32.Final.jar:5.4.32.Final] 在 org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) ~[hibernate-core-5.4.32.Final.jar:5.5. .32.Final] 在 org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.ja va:585) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final] 在 org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:149) ~[hibernate-core-5.4 .32.Final.jar:5.4.32.Final] 在 org.hibernate.collection.internal.PersistentSet.hashCode(PersistentSet.java:458) ~[hibernate-core-5.4.32.Final.jar:5.4.32. Final] at com.springdata.associations.onetomay.entities.Programmer.hashCode(Programmer.java:22) ~[classes/:na] at java.base/java.util.HashMap.hash(HashMap.java:340) ~ [na:na] 在 java.base/java.util.HashMap.put(HashMap.java:612) ~[na:na] 在 java.base/java.util.HashSet.add(HashSet.java:221) ~ [无：无]