在具有双向连接的特定实体上运行 findById(Long id) Jpa 方法时出现“java.lang.***Error: null”

Posted 2023-02-26

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【中文标题】在具有双向连接的特定实体上运行 findById(Long id) Jpa 方法时出现“java.lang.***Error: null”【英文标题】：Having a `java.lang.***Error: null` when running a findById(Long id) Jpa method on a specific Entity with bidirectional connection 【发布时间】：2019-04-22 06:28:10 【问题描述】：

我在使用特定实体 (CtThhlastikaPressThreats) 的 findById Jpa 方法时遇到问题。为了更清楚地了解该项目，它使用了 Spring Boot、Jpa 和 mysql。存在具有双向连接@OneToMany 和@ManyToOne 的实体，同时它们之间还有mappedBy 和JoinColumn。我遇到问题的特定实体具有与 DeigmaThhlastikwn 实体类似的双向连接（没问题，我曾经遇到过 *** 异常，但通过 @JsonIgnore 的注释解决了. 我在这个上试过了，你可以在@ManyToOne 一侧看到DeigmaThhlastikwnXPressThreats 实体，但它没有用）

CtThhlastikaPressThreatsController 休息控制器：

@RestController
@RequestMapping(CtThhlastikaPressThreatsController.BASE_URL)
public class CtThhlastikaPressThreatsController 

public static final String BASE_URL = "/v1/ctThhlastikaPressThreats";

private CtThhlastikaPressThreatsService ctThhlastikaPressThreatsService;

@Autowired
private CtThhlastikaPressThreatsRepositoryImpl ctThhlastikaPressThreatsRepository;

public CtThhlastikaPressThreatsController(CtThhlastikaPressThreatsService ctThhlastikaPressThreatsService) 
    this.ctThhlastikaPressThreatsService = ctThhlastikaPressThreatsService;


@CrossOrigin
@GetMapping("/id")
public CtThhlastikaPressThreats findById(@PathVariable Long id)
    return ctThhlastikaPressThreatsRepository.findCtThhlastikaPressThreatsById(id);


@CrossOrigin
@PostMapping()
public CtThhlastikaPressThreats addPressThreat(@RequestBody CtThhlastikaPressThreatDTO ctThhlastikaPressThreatDTO)
    try 
        return ctThhlastikaPressThreatsService.addPressThreat(ctThhlastikaPressThreatDTO);
    catch (Exception e)
        throw e;
    


@CrossOrigin
@GetMapping("/getAllActCodes")
public ArrayList<String> getAllActCodes()
    try 
        return ctThhlastikaPressThreatsService.getAllActCodes();
    catch (Exception e)
        throw e;

CtThhlastikaPressThreats 实体：

package com.teicm.kerkinibackend.domain;

import javax.persistence.*;
import java.util.HashSet;
import java.util.Set;

@Entity
public class CtThhlastikaPressThreats 

@Id
@Column(name = "id", nullable = false)
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;

@OneToMany(cascade = CascadeType.ALL, mappedBy = "ctThhlastikaPressThreats")
private Set<DeigmaThhlastikwnXPressThreats> deigmaThhlastikwnXPressThreatsSet = new HashSet<>();

@Column(name = "act_code", unique = true, length = 50)
private String actCode;

@Column(name = "description_en")
private String descriptionEn;

@Column(name = "remarks")
private String remarks;

public CtThhlastikaPressThreats addPressThreat(DeigmaThhlastikwnXPressThreats deigmaThhlastikwnXPressThreats)
    deigmaThhlastikwnXPressThreats.setCtThhlastikaPressThreats(this);
    this.deigmaThhlastikwnXPressThreatsSet.add(deigmaThhlastikwnXPressThreats);
    return this;


public CtThhlastikaPressThreats() 


public CtThhlastikaPressThreats(String actCode, Set<DeigmaThhlastikwnXPressThreats> deigmaThhlastikwnXPressThreatsSet, String descriptionEn, String remarks) 
    this.actCode = actCode;
    this.deigmaThhlastikwnXPressThreatsSet = deigmaThhlastikwnXPressThreatsSet;
    this.descriptionEn = descriptionEn;
    this.remarks = remarks;


public Long getId() 
    return id;


public void setId(Long id) 
    this.id = id;


public String getActCode() 
    return actCode;


public void setActCode(String actCode) 
    this.actCode = actCode;


public Set<DeigmaThhlastikwnXPressThreats> getDeigmaThhlastikwnXPressThreatsSet() 
    return deigmaThhlastikwnXPressThreatsSet;


public void setDeigmaThhlastikwnXPressThreatsSet(Set<DeigmaThhlastikwnXPressThreats> deigmaThhlastikwnXPressThreatsSet) 
    this.deigmaThhlastikwnXPressThreatsSet = deigmaThhlastikwnXPressThreatsSet;


public String getDescriptionEn() 
    return descriptionEn;


public void setDescriptionEn(String descriptionEn) 
    this.descriptionEn = descriptionEn;


public String getRemarks() 
    return remarks;


public void setRemarks(String remarks) 
    this.remarks = remarks;

DeigmaThhlastikwnXPressThreats 实体：

package com.teicm.kerkinibackend.domain;

import com.fasterxml.jackson.annotation.JsonIgnore;

import javax.persistence.*;

@Entity
public class DeigmaThhlastikwnXPressThreats 

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

@ManyToOne(fetch = FetchType.EAGER)
@JoinColumn(name = "deigma_thhlastikwn_id")
@JsonIgnore
private DeigmaThhlastikwn deigmaThhlastikwn;

@ManyToOne(fetch = FetchType.EAGER)
@JoinColumn(name = "ct_thhlastika_press_threats_id")
@JsonIgnore
private CtThhlastikaPressThreats ctThhlastikaPressThreats;

@Column(name = "kwdikos_eidous", length = 50)
private String kwdikosEidous;

@Column(name = "press_threat", length = 50)
private String pressThreat;

@Column(name = "importance", length = 50)
private String importance;

public DeigmaThhlastikwnXPressThreats() 


public DeigmaThhlastikwnXPressThreats(DeigmaThhlastikwn deigmaThhlastikwn, CtThhlastikaPressThreats ctThhlastikaPressThreats, String kwdikosEidous, String pressThreat, String importance) 
    this.deigmaThhlastikwn = deigmaThhlastikwn;
    this.ctThhlastikaPressThreats = ctThhlastikaPressThreats;
    this.kwdikosEidous = kwdikosEidous;
    this.pressThreat = pressThreat;
    this.importance = importance;


public Long getId() 
    return id;


public void setId(Long id) 
    this.id = id;


public DeigmaThhlastikwn getDeigmaThhlastikwn() 
    return deigmaThhlastikwn;


public void setDeigmaThhlastikwn(DeigmaThhlastikwn deigmaThhlastikwn) 
    this.deigmaThhlastikwn = deigmaThhlastikwn;


public CtThhlastikaPressThreats getCtThhlastikaPressThreats() 
    return ctThhlastikaPressThreats;


public void setCtThhlastikaPressThreats(CtThhlastikaPressThreats ctThhlastikaPressThreats) 
    this.ctThhlastikaPressThreats = ctThhlastikaPressThreats;


public String getKwdikosEidous() 
    return kwdikosEidous;


public void setKwdikosEidous(String kwdikosEidous) 
    this.kwdikosEidous = kwdikosEidous;


public String getPressThreat() 
    return pressThreat;


public void setPressThreat(String pressThreat) 
    this.pressThreat = pressThreat;


public String getImportance() 
    return importance;


public void setImportance(String importance) 
    this.importance = importance;

DeigmaThhlastikwn 实体：

package com.teicm.kerkinibackend.domain;

import javax.persistence.*;
import java.sql.Date;
import java.sql.Time;
import java.util.HashSet;
import java.util.Set;

@Entity
@Table(name = "deigma_thhlastikwn")
public class DeigmaThhlastikwn 

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id", nullable = false)
private Long id;

@OneToMany(cascade = CascadeType.ALL, mappedBy = "deigmaThhlastikwn", fetch = FetchType.EAGER)
private Set<DeigmaThhlastikwnXEidh> deigmaThhlastikwnXEidhSet = new HashSet<>();

@OneToMany(cascade = CascadeType.ALL, mappedBy = "deigmaThhlastikwn", fetch = FetchType.EAGER)
private Set<DeigmaThhlastikwnXPressThreats> deigmaThhlastikwnXPressThreatsSet = new HashSet<>();

@Column(name = "kwdikos_deigmatos", nullable = false)
private String kwdikosDeigmatolhpsias;

@Column(name = "xrhmatodothsh")
private String xrhmatodothsh;

@Column(name = "ereunhths")
private String ereunhths;

@Column(name = "topothesia")
private String topothesia;

@Column(name = "date")
private Date date;

@Column(name = "time")
private Time time;

@Column(name = "diarkeia", length = 40)
private String diarkeia;

@Column(name = "tupos_vlasthshs")
private String tuposVlasthshs;

@Column(name = "tupos_oikotopou")
private String tupos_Oikotopou;

@Column(name = "epifaneia_deigmatolhpsias")
private Integer epifaneiaDeigmatolhpsias;

@Column(name = "latitude_egsa")
private Double latitudeEGSA;

@Column(name = "longitude_egsa")
private Double longitudeEGSA;

//    Preferred for Google Maps Markers
@Column(name = "latitude_wgs84")
private Double latitudeWGS84;

//    Preferred for Google Maps Markers
@Column(name = "longitude_wgs84")
private Double longitudeWGS84;

@Column(name = "grid_cell", length = 30)
private String gridCell;

@Column(name = "kwdikos_natura", length = 20)
private String kwdikosNatura;

@Column(name = "methodos_deigmatolhpsias")
private String methodosDeigmatolhpsias;

@Column(name = "parathrhseis")
private String parathrhseis;

@Column(name = "nomos")
private String nomos;

@Column(name = "picture")
@Lob
private Byte picture;

@Column(name = "file")
@Lob
private Byte file;

public DeigmaThhlastikwn() 


public DeigmaThhlastikwn(Set<DeigmaThhlastikwnXEidh> deigmaThhlastikwnXEidhSet, Set<DeigmaThhlastikwnXPressThreats> deigmaThhlastikwnXPressThreatsSet, String kwdikosDeigmatolhpsias, String xrhmatodothsh, String ereunhths, String topothesia, Date date, Time time, String diarkeia, String tuposVlasthshs, String tupos_Oikotopou, Integer epifaneiaDeigmatolhpsias, Double latitudeEGSA, Double longitudeEGSA, Double latitudeWGS84, Double longitudeWGS84, String gridCell, String kwdikosNatura, String methodosDeigmatolhpsias, String parathrhseis, String nomos, Byte picture, Byte file) 
    this.deigmaThhlastikwnXEidhSet = deigmaThhlastikwnXEidhSet;
    this.deigmaThhlastikwnXPressThreatsSet = deigmaThhlastikwnXPressThreatsSet;
    this.kwdikosDeigmatolhpsias = kwdikosDeigmatolhpsias;
    this.xrhmatodothsh = xrhmatodothsh;
    this.ereunhths = ereunhths;
    this.topothesia = topothesia;
    this.date = date;
    this.time = time;
    this.diarkeia = diarkeia;
    this.tuposVlasthshs = tuposVlasthshs;
    this.tupos_Oikotopou = tupos_Oikotopou;
    this.epifaneiaDeigmatolhpsias = epifaneiaDeigmatolhpsias;
    this.latitudeEGSA = latitudeEGSA;
    this.longitudeEGSA = longitudeEGSA;
    this.latitudeWGS84 = latitudeWGS84;
    this.longitudeWGS84 = longitudeWGS84;
    this.gridCell = gridCell;
    this.kwdikosNatura = kwdikosNatura;
    this.methodosDeigmatolhpsias = methodosDeigmatolhpsias;
    this.parathrhseis = parathrhseis;
    this.nomos = nomos;
    this.picture = picture;
    this.file = file;


// Custom method for adding a new PressThreat for a specific DeigmaThhlastikwn allong with specifying the parent's id in the child object.
public DeigmaThhlastikwn addPressThreat(DeigmaThhlastikwnXPressThreats deigmaThhlastikwnXPressThreats)
    deigmaThhlastikwnXPressThreats.setDeigmaThhlastikwn(this);
    this.deigmaThhlastikwnXPressThreatsSet.add(deigmaThhlastikwnXPressThreats);
    return this;


public DeigmaThhlastikwn addXEidh(DeigmaThhlastikwnXEidh deigmaThhlastikwnXEidh)
    deigmaThhlastikwnXEidh.setDeigmaThhlastikwn(this);
    this.deigmaThhlastikwnXEidhSet.add(deigmaThhlastikwnXEidh);
    return this;


public Long getId() 
    return id;


public void setId(Long id) 
    this.id = id;


public Set<DeigmaThhlastikwnXEidh> getDeigmaThhlastikwnXEidhSet() 
    return deigmaThhlastikwnXEidhSet;


public void setDeigmaThhlastikwnXEidhSet(Set<DeigmaThhlastikwnXEidh> deigmaThhlastikwnXEidhSet) 
    this.deigmaThhlastikwnXEidhSet = deigmaThhlastikwnXEidhSet;


public Set<DeigmaThhlastikwnXPressThreats> getDeigmaThhlastikwnXPressThreatsSet() 
    return deigmaThhlastikwnXPressThreatsSet;


public void setDeigmaThhlastikwnXPressThreatsSet(Set<DeigmaThhlastikwnXPressThreats> deigmaThhlastikwnXPressThreatsSet) 
    this.deigmaThhlastikwnXPressThreatsSet = deigmaThhlastikwnXPressThreatsSet;


public String getKwdikosDeigmatolhpsias() 
    return kwdikosDeigmatolhpsias;


public void setKwdikosDeigmatolhpsias(String kwdikosDeigmatolhpsias) 
    this.kwdikosDeigmatolhpsias = kwdikosDeigmatolhpsias;


public String getXrhmatodothsh() 
    return xrhmatodothsh;


public void setXrhmatodothsh(String xrhmatodothsh) 
    this.xrhmatodothsh = xrhmatodothsh;


public String getEreunhths() 
    return ereunhths;


public void setEreunhths(String ereunhths) 
    this.ereunhths = ereunhths;


public String getTopothesia() 
    return topothesia;


public void setTopothesia(String topothesia) 
    this.topothesia = topothesia;


public Date getDate() 
    return date;


public void setDate(Date date) 
    this.date = date;


public Time getTime() 
    return time;


public void setTime(Time time) 
    this.time = time;


public String getDiarkeia() 
    return diarkeia;


public void setDiarkeia(String diarkeia) 
    this.diarkeia = diarkeia;


public String getTuposVlasthshs() 
    return tuposVlasthshs;


public void setTuposVlasthshs(String tuposVlasthshs) 
    this.tuposVlasthshs = tuposVlasthshs;


public String getTupos_Oikotopou() 
    return tupos_Oikotopou;


public void setTupos_Oikotopou(String tupos_Oikotopou) 
    this.tupos_Oikotopou = tupos_Oikotopou;


public Integer getEpifaneiaDeigmatolhpsias() 
    return epifaneiaDeigmatolhpsias;


public void setEpifaneiaDeigmatolhpsias(Integer epifaneiaDeigmatolhpsias) 
    this.epifaneiaDeigmatolhpsias = epifaneiaDeigmatolhpsias;


public Double getLatitudeEGSA() 
    return latitudeEGSA;


public void setLatitudeEGSA(Double latitudeEGSA) 
    this.latitudeEGSA = latitudeEGSA;


public Double getLongitudeEGSA() 
    return longitudeEGSA;


public void setLongitudeEGSA(Double longitudeEGSA) 
    this.longitudeEGSA = longitudeEGSA;


public Double getLatitudeWGS84() 
    return latitudeWGS84;


public void setLatitudeWGS84(Double latitudeWGS84) 
    this.latitudeWGS84 = latitudeWGS84;


public Double getLongitudeWGS84() 
    return longitudeWGS84;


public void setLongitudeWGS84(Double longitudeWGS84) 
    this.longitudeWGS84 = longitudeWGS84;


public String getGridCell() 
    return gridCell;


public void setGridCell(String gridCell) 
    this.gridCell = gridCell;


public String getKwdikosNatura() 
    return kwdikosNatura;


public void setKwdikosNatura(String kwdikosNatura) 
    this.kwdikosNatura = kwdikosNatura;


public String getMethodosDeigmatolhpsias() 
    return methodosDeigmatolhpsias;


public void setMethodosDeigmatolhpsias(String methodosDeigmatolhpsias) 
    this.methodosDeigmatolhpsias = methodosDeigmatolhpsias;


public String getParathrhseis() 
    return parathrhseis;


public void setParathrhseis(String parathrhseis) 
    this.parathrhseis = parathrhseis;


public String getNomos() 
    return nomos;


public void setNomos(String nomos) 
    this.nomos = nomos;


public Byte getPicture() 
    return picture;


public void setPicture(Byte picture) 
    this.picture = picture;


public Byte getFile() 
    return file;


public void setFile(Byte file) 
    this.file = file;

只是通知一下，添加一个新的CtThhlastikaPressThreats 已成功完成。此外，MySQL 架构是在 Run 上自动创建的。

项目的github页面在https://github.com/alexgil1994/kerkinibackend

错误的堆栈跟踪是（并且它保持相同的递归方式，我没有插入整个堆栈，因为您可以看到它已经重复自身）：

2018-11-19 21:59:48.808 ERROR 1372 --- [nio-8080-exec-3] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Handler dispatch failed; nested exception is java.lang.***Error] with root cause

java.lang.***Error: null
at org.springframework.data.repository.util.ClassUtils.unwrapReflectionException(ClassUtils.java:154) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:646) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:608) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$invoke$3(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:59) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294) ~[spring-tx-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:117) ~[spring-data-jpa-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:93) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:61) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at com.sun.proxy.$Proxy112.findCtThhlastikaPressThreatsById(Unknown Source) ~[na:na]
at sun.reflect.GeneratedMethodAccessor63.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_181]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_181]
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:343) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:206) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at com.sun.proxy.$Proxy94.findCtThhlastikaPressThreatsById(Unknown Source) ~[na:na]
at com.teicm.kerkinibackend.repositories.CtThhlastikaPressThreatsRepositoryImpl.findCtThhlastikaPressThreatsById(CtThhlastikaPressThreatsRepositoryImpl.java:37) ~[classes/:na]
at com.teicm.kerkinibackend.repositories.CtThhlastikaPressThreatsRepositoryImpl$$FastClassBySpringCGLIB$$f23e415a.invoke(<generated>) ~[classes/:na]
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:746) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at com.teicm.kerkinibackend.repositories.CtThhlastikaPressThreatsRepositoryImpl$$EnhancerBySpringCGLIB$$b6491b5e.findCtThhlastikaPressThreatsById(<generated>) ~[classes/:na]
at sun.reflect.GeneratedMethodAccessor64.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_181]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_181]
at org.springframework.data.repository.core.support.RepositoryComposition$RepositoryFragments.invoke(RepositoryComposition.java:359) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryComposition.invoke(RepositoryComposition.java:200) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:644) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:608) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$invoke$3(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:59) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294) ~[spring-tx-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:117) ~[spring-data-jpa-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:93) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:61) ~[spring-data-commons-2.1.1.RELEASE.jar:2.1.1.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at com.sun.proxy.$Proxy112.findCtThhlastikaPressThreatsById(Unknown Source) ~[na:na]
at sun.reflect.GeneratedMethodAccessor63.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_181]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_181]
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:343) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:206) ~[spring-aop-5.1.1.RELEASE.jar:5.1.1.RELEASE]
at com.sun.proxy.$Proxy94.findCtThhlastikaPressThreatsById(Unknown Source) ~[na:na]
at com.teicm.kerkinibackend.repositories.CtThhlastikaPressThreatsRepositoryImpl.findCtThhlastikaPressThreatsById(CtThhlastikaPressThreatsRepositoryImpl.java:37) ~[classes/:na]

对于任何不当行为，我深表歉意，该项目处于我论文的早期阶段。

非常感谢任何帮助。

更新 - 已解决：

按照答案中的建议解决了问题。在我的一个 cmets 的正确答案下有进一步的解释。另外，如果有人有兴趣查看所有更改的详细信息，您可以查看解决问题的提交： https://github.com/alexgil1994/kerkinibackend/commit/230c1df96623363c61317216913b310c1c7ec231

【问题讨论】：

为什么要为所有内容设置FetchType.EAGER？我没有仔细追踪，因为您在这里有很多代码，但我怀疑您有无限的 fetch 递归。 FetchType.EAGER 通常是禁止的。仅当您专门查询获取关系时才应获取关系。您好，FetchType.EAGER 是我试图做的其他事情留下的，删除它似乎与问题没有任何关系，错误仍然像以前一样发生。我相信你，但我不愿意看任何有那些 fetch 类型急切的东西。代码太多了。为什么不能删除所有额外的字段并从问题的基本示例开始？ 【参考方案1】：

我首先将以下内容添加到您的 application.properties 文件中，这样您就可以准确地看到调用了哪些 sql 语句。

# Log sql statements and their parameters
logging.level.org.hibernate.SQL=debug
logging.level.org.hibernate.type.descriptor.sql=trace

@JsonIgnore 不会帮助读取数据。只有当您使用 Jackson 将对象转换为 Json 时才会出现这种情况。即当您从 RestController 返回数据时。

我刚刚查看了 github 上 repo 中的 ctThhlastikaPressThreatsRepository.findCtThhlastikaPressThreatsById 方法。它似乎在调用自己，这会导致堆栈溢出。

public CtThhlastikaPressThreats findCtThhlastikaPressThreatsById(Long id)
    try 
        // TODO: 11/17/2018 !!! -- Try as an Optional findById(id) instead!!!
        return ctThhlastikaPressThreatsRepository.findCtThhlastikaPressThreatsById(id);
    catch (Exception e)
        throw  e;

您如何使用 spring 和 jpa 非常令人困惑。我要么使用你自己的@Repository（你拥有的 Impl 版本），要么坚持扩展 CrudRepository。不要尝试两者都做。

如果你想使用 CrudRepository，你只需要拥有你已经拥有的东西。

public interface CtThhlastikaPressThreatsRepository extends CrudRepository<CtThhlastikaPressThreats, Long>, org.springframework.data.repository.Repository<CtThhlastikaPressThreats, Long> 

    Optional<CtThhlastikaPressThreats> findById(Long id);

    CtThhlastikaPressThreats findCtThhlastikaPressThreatsById(Long id);

    @Query(nativeQuery = true, value = "SELECT DISTINCT ct.act_code FROM ct_thhlastika_press_threats ct ORDER BY act_code ASC")
    ArrayList<String> findDistinctByActCodeOrderByActCode();

您应该能够删除 Impl 版本并使用它。

我建议你编写一些测试类来简化调试。

例如

@RunWith(SpringJUnit4ClassRunner.class)
@DataJpaTest
public class CtThhlastikaPressThreatsRepositoryImplTest 

    @Autowired
    private CtThhlastikaPressThreatsRepository ctThhlastikaPressThreatsRepository;

    @Test
    public void findByIdTest() 
        CtThhlastikaPressThreats pressThreats = new CtThhlastikaPressThreats();
        pressThreats.setActCode("actcode");
        pressThreats.setDescriptionEn("description");
        pressThreats.setRemarks("remarks");
        ctThhlastikaPressThreatsRepository.save(pressThreats);

        CtThhlastikaPressThreats found = ctThhlastikaPressThreatsRepository.findById(pressThreats.getId()).orElse(null);
        assertEquals("description", found.getDescriptionEn());

        CtThhlastikaPressThreats found2 = ctThhlastikaPressThreatsRepository.findCtThhlastikaPressThreatsById(pressThreats.getId());
        assertEquals("description", found2.getDescriptionEn());
    

    @Test
    public void listCodesTest() 
        CtThhlastikaPressThreats pressThreats = new CtThhlastikaPressThreats();
        pressThreats.setActCode("actcode1");
        pressThreats.setDescriptionEn("description1");
        pressThreats.setRemarks("remarks1");
        ctThhlastikaPressThreatsRepository.save(pressThreats);
        pressThreats = new CtThhlastikaPressThreats();
        pressThreats.setActCode("actcode2");
        pressThreats.setDescriptionEn("description2");
        pressThreats.setRemarks("remarks2");
        ctThhlastikaPressThreatsRepository.save(pressThreats);
        List<String> expected = Arrays.asList(new String[] "actcode1", "actcode2");

        ArrayList<String> found = ctThhlastikaPressThreatsRepository.findDistinctByActCodeOrderByActCode();
        assertTrue(found.containsAll(expected) && expected.containsAll(found));

【讨论】：

您好，感谢您抽出宝贵的时间来回答，我确实插入了它们并看到了工作请求的操作，例如将CtThhlastikaPressThreats 添加到数据库但对于findById(id) 或findCtThhlastikaPressThreatById(id) 或即使findAll() 请求它没有帮助，它直接进入错误。这可能意味着双向连接有问题？不过，谢谢，我一直在寻找这种检查查询功能。请随时提出其他建议。是的，你是对的，当我从RestController 所需的数据返回时，@JsonIgnore 帮助我解决了另一个问题，该数据也具有双向引用。但我相信这是一个不同的问题，实体 (DeigmaThhlastika) 工作正常（即使它具有类似的双向连接。好的，我将重构它并仅使用接口，尽管我认为它是一个更有条理的结构，但我想我错了。以这种方式尝试虽然看起来错误仍然相同，但正如您所说，当使用除自定义查询findDistinctByActCodeOrderByActCode 之外的任何find 方法时，它看起来确实会调用自身。我显然在某个地方做错了什么，但我找不到它。我确实按照您的建议重构了整个项目，我删除了每个存储库的 RepositoryImpl 并且仅使用接口存储库。在为CtThhlastikaEidh 实施了一些工作以将其与CtThhlastikaPressThreats 进行比较后，我发现那个工作正常（它们具有基本相同的双向映射），因此需要进行更多工作并更改CtThhlastikaPressThreats 的一个注释id 专栏按预期工作！感谢您的所有建议，除了解决它之外，我还通过您的帮助学到了一些东西。开始测试！

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