为啥无法在类上找到适当的构造函数

Posted 2023-02-26

【中文标题】为啥无法在类上找到适当的构造函数

【英文标题】：Hibernate: Unable to locate appropriate constructor on class in hql为什么无法在类上找到适当的构造函数

【发布时间】：2021-10-25 08:26:30

【问题描述】：

我收到错误：

org.hibernate.hql.internal.ast.QuerySyntaxException：无法在类 [com.meetzen.Dto.profileJoinDto] 上找到适当的构造函数。预期的参数是：java.lang.String、java.lang.String、java.lang.String、java.lang.String、java.lang.String、java.lang.String [SELECT new com.meetzen.Dto.profileJoinDto( r.username, r.email, r.contact, p.bio, p.website, p.gender) FROM com.meetzen.Entity.profileEntity p JOIN p.registrationEntity r WHERE r.u_id = ?1]

代码如下：

profileEntity

package com.meetzen.Entity;

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
import javax.persistence.Table;

@Entity
@Table(name = "profile_master")
public class profileEntity 
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private int p_id;
    private String website;
    private String bio;
    private String gender;

    @OneToOne(cascade = CascadeType.ALL, targetEntity = registrationEntity.class)
    @JoinColumn(name = "user_id", referencedColumnName = "u_id")

    private registrationEntity registrationEntity;

    // getter setter

注册实体

package com.meetzen.Entity;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "registration_master")
public class registrationEntity 
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private int u_id;
    @Column(unique = true)
    private String email;
    private String username;
    private String password;
    private String contact;
    private String date;

    // getter setter

profileJoinDto

package com.meetzen.Dto;

import javax.persistence.Id;

public class profileJoinDto 
    private Integer u_id;
    private Integer p_id;
    private String email;
    private String username;
    private String password;
    private String contact;
    private String date;
    private String website;
    private String bio;
    private String gender;

    // getter setter

profileRepo

package com.meetzen.Repository;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;

import com.meetzen.Dto.profileJoinDto;
import com.meetzen.Entity.profileEntity;

public interface profileRepo extends JpaRepository<profileEntity, Integer>
    @Query("SELECT new com.meetzen.Dto.profileJoinDto(r.username, r.email, r.contact, p.bio, p.website, p.gender) FROM profileEntity p JOIN p.registrationEntity r WHERE r.u_id = ?1")
    profileJoinDto findById(int id);

堆栈跟踪

Caused by: org.hibernate.hql.internal.ast.QuerySyntaxException: Unable to locate appropriate constructor on class [com.meetzen.Dto.profileJoinDto]. Expected arguments are: java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String [SELECT new com.meetzen.Dto.profileJoinDto(r.username, r.email, r.contact, p.bio, p.website, p.gender) FROM com.meetzen.Entity.profileEntity p JOIN p.registrationEntity r WHERE r.u_id = ?1]
    at org.hibernate.hql.internal.ast.QuerySyntaxException.convert(QuerySyntaxException.java:74) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.hql.internal.ast.ErrorTracker.throwQueryException(ErrorTracker.java:93) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:282) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:192) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:144) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:113) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:73) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:162) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.internal.AbstractSharedSessionContract.getQueryPlan(AbstractSharedSessionContract.java:613) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:725) ~[hibernate-core-5.4.32.Final.jar:5.4.32.Final]
    ... 86 common frames omitted

【参考方案1】：

…FROM profileEntity p JOIN p.registrationEntity p…

您在这里使用了两次相同的别名 (p)。试试FROM profileEntity p JOIN p.registrationEntity r。

【参考方案2】：

我得到了答案，我将我的 jpql 查询更改为 sql 查询并将我的 profileJoinDto 类转换为接口...

代码更改：

profileJoinDto:

package com.meetzen.Dto;

public interface profileJoinDto 
    public Integer getU_id();
    public Integer getP_id();
    public String getEmail();
    public String getUsername();
    public String getPassword();
    public String getContact();
    public String getDate();
    public String getWebsite();
    public String getBio();
    public String getGender();

下面的jpql查询改为sql查询

profileRepo：

package com.meetzen.Repository;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;

import com.meetzen.Dto.profileJoinDto;
import com.meetzen.Entity.profileEntity;

public interface profileRepo extends JpaRepository<profileEntity, Integer>
    //JPQL QUERY
    //@Query("SELECT new com.meetzen.Dto.profileJoinDto(r.username, r.email, r.contact, p.bio, p.website, p.gender) FROM profileEntity p JOIN p.registrationEntity r WHERE r.u_id = ?1")

    // SQL QUERY
    @Query(nativeQuery = true, value = "SELECT * FROM registration_master rm INNER JOIN profile_master pm ON rm.u_id = pm.user_id WHERE rm.u_id = ?")
    profileJoinDto findById(int id);