Spring Hibernate在查询中添加_

Question

I am havgin a problem creating classes.

Vehiculo (Vechicle)

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


/**
 * The persistent class for the vehiculo database table.
 * 
 */
@Entity
@Table(name="vehiculo")
@NamedQuery(name="Vehiculo.findAll", query="SELECT v FROM Vehiculo v")
public class Vehiculo implements Serializable {
    private static final long serialVersionUID = 1L;
    private int idvehiculo;
    private int capacidad;
    private String matricula;
    private int vacante;
    private List<PersonaFisica> personaFisicas;
    private TipoVehiculo tipoVehiculo;

    public Vehiculo() {
    }


    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(unique=true, nullable=false, name= "idvehiculo")
    public int getIdvehiculo() {
        return this.idvehiculo;
    }

    public void setIdvehiculo(int idvehiculo) {
        this.idvehiculo = idvehiculo;
    }


    @Column(nullable=false)
    public int getCapacidad() {
        return this.capacidad;
    }

    public void setCapacidad(int capacidad) {
        this.capacidad = capacidad;
    }


    @Column(length=12)
    public String getMatricula() {
        return this.matricula;
    }

    public void setMatricula(String matricula) {
        this.matricula = matricula;
    }


    @Column(nullable=false)
    public int getVacante() {
        return this.vacante;
    }

    public void setVacante(int vacante) {
        this.vacante = vacante;
    }


    //bi-directional many-to-one association to PersonaFisica
    @OneToMany(mappedBy="vehiculo")
    public List<PersonaFisica> getPersonaFisicas() {
        return this.personaFisicas;
    }

    public void setPersonaFisicas(List<PersonaFisica> personaFisicas) {
        this.personaFisicas = personaFisicas;
    }

    public PersonaFisica addPersonaFisica(PersonaFisica personaFisica) {
        getPersonaFisicas().add(personaFisica);
        personaFisica.setVehiculo(this);

        return personaFisica;
    }

    public PersonaFisica removePersonaFisica(PersonaFisica personaFisica) {
        getPersonaFisicas().remove(personaFisica);
        personaFisica.setVehiculo(null);

        return personaFisica;
    }


    //bi-directional many-to-one association to TipoVehiculo
    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="tipo_vehiculo_idTipoVehiculo", nullable=false, referencedColumnName="idTipoVehiculo")
    public TipoVehiculo getTipoVehiculo() {
        return this.tipoVehiculo;
    }

    public void setTipoVehiculo(TipoVehiculo tipoVehiculo) {
        this.tipoVehiculo = tipoVehiculo;
    }

}

VehicleType

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


/**
 * The persistent class for the tipo_vehiculo database table.
 * 
 */
@Entity
@Table(name="tipo_vehiculo")
@NamedQuery(name="TipoVehiculo.findAll", query="SELECT t FROM TipoVehiculo t")
public class TipoVehiculo implements Serializable {
    private static final long serialVersionUID = 1L;
    private int idTipoVehiculo;
    private String codigo;
    private String descripcion;
    private List<Vehiculo> vehiculos;

    public TipoVehiculo() {
    }


    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(unique=true, nullable=false,name="idTipoVehiculo")
    public int getIdTipoVehiculo() {
        return this.idTipoVehiculo;
    }

    public void setIdTipoVehiculo(int idTipoVehiculo) {
        this.idTipoVehiculo = idTipoVehiculo;
    }


    @Column(nullable=false, length=20)
    public String getCodigo() {
        return this.codigo;
    }

    public void setCodigo(String codigo) {
        this.codigo = codigo;
    }


    @Column(length=140)
    public String getDescripcion() {
        return this.descripcion;
    }

    public void setDescripcion(String descripcion) {
        this.descripcion = descripcion;
    }


    //bi-directional many-to-one association to Vehiculo
    @OneToMany(mappedBy="tipoVehiculo")
    public List<Vehiculo> getVehiculos() {
        return this.vehiculos;
    }

    public void setVehiculos(List<Vehiculo> vehiculos) {
        this.vehiculos = vehiculos;
    }

    public Vehiculo addVehiculo(Vehiculo vehiculo) {
        getVehiculos().add(vehiculo);
        vehiculo.setTipoVehiculo(this);

        return vehiculo;
    }

    public Vehiculo removeVehiculo(Vehiculo vehiculo) {
        getVehiculos().remove(vehiculo);
        vehiculo.setTipoVehiculo(null);

        return vehiculo;
    }

}

The problem is, when hibernate tries to do the query, it does:

select vehiculo0_.idvehiculo as idvehicu1_25_, vehiculo0_.capacidad as capacida2_25_, 
        vehiculo0_.matricula as matricul3_25_, vehiculo0_.tipo_vehiculo_id_tipo_vehiculo as tipo_veh5_25_, 
        vehiculo0_.vacante as vacante4_25_ 
 from vehiculo vehiculo0_

as you can see, the atribute is called: tipo_vehiculo_idTipoVehiculo, but in the query it keeps adding "_" looking like this: tipo_vehiculo_id_tipo_vehiculo ....

Looking in internet i have seen that i can use a new NamingStrategy to avoid this situation, the class i have found is this:

package net.petrikainulainen.hibernate.util;
import org.hibernate.cfg.ImprovedNamingStrategy;

/**
 * A custom naming strategy implementation which uses following naming conventions:
 * <ul>
 *     <li>Table names are lower case and in plural form. Words are separated with '_' character.</li>
 *     <li>Column names are lower case and words are separated with '_' character.</li>
 * </ul>
 * @author Petri Kainulainen
 */
public class CustomNamingStrategy extends ImprovedNamingStrategy {

    private static final String PLURAL_SUFFIX = "s";

    /**
     * Transforms class names to table names by using the described naming conventions.
     * @param className
     * @return  The constructed table name.
     */
    @Override
    public String classToTableName(String className) {
        String tableNameInSingularForm = super.classToTableName(className);
        return transformToPluralForm(tableNameInSingularForm);
    }

    private String transformToPluralForm(String tableNameInSingularForm) {
        StringBuilder pluralForm = new StringBuilder();

        pluralForm.append(tableNameInSingularForm);
        pluralForm.append(PLURAL_SUFFIX);

        return pluralForm.toString();
    }
}

But i dont see anywhere about the "_" .. i have also tried addind the next code, to see if it works, but nothing yet.

      @Override
        public String propertyToColumnName(String propertyName) {
            // TODO Auto-generated method stub
            return propertyName;
        }

         @Override
        public String columnName(String columnName) {
            // TODO Auto-generated method stub
            return columnName;
        }

I am using HIbernate+JPA, Spring with an application.yml that looks like this: and all the possible types of org.hibernate.dialect, but no results

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/gotowork_db?useSSL=false
    username: root
    password: root
  jpa:
    show-sql: true
    hibernate:
      naming:
        strategy: es.gfi.CustomNamingStrategy
    properties:
      hibernate:
        dialect: org.hibernate.dialect.MySQLDialect

Is there a way to avoid the camelCap changing to "_" ???... and not having to change the DB column names?

Thanks

Answer 1

Try this piece of code where in as per your requirement you can do a logical check and replace column name text accordingly.

public class Temp extends ImprovedNamingStrategy {

    @Override
    public String columnName(String columnName) {
        if(columnName.contains("id_tipo_vehiculo")){
            String replacedString = columnName.replace("id_tipo_vehiculo", "idTipoVehiculo");
            return replacedString;
        }else{
            return columnName; 
        }
    }

}

Answer 2

Just found the problem after hours of testing the thing is that the naming strategy used, changes all the capital letters for a "_"+lowercase when creating the query.

As you can see in the code in the question in the

//bi-directional many-to-one association to TipoVehiculo
    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="tipo_vehiculo_idTipoVehiculo", nullable=false, referencedColumnName="idTipoVehiculo")
    public TipoVehiculo getTipoVehiculo() {
        return this.tipoVehiculo;
    }

it does: tipo_vehiculo_id_tipo_vehiculo, making the query look like:

SELECT 
    vehiculo0_.idvehiculo AS idvehicu1_25_,
    vehiculo0_.capacidad AS capacida2_25_,
    vehiculo0_.matricula AS matricul3_25_,
    vehiculo0_.tipo_vehiculo_id_tipo_vehiculo AS tipo_veh5_25_,
    vehiculo0_.vacante AS vacante4_25_
FROM
    vehiculo vehiculo0_

so i have changed to this way:

//bi-directional many-to-one association to TipoVehiculo
    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="tipo_vehiculo_idtipovehiculo", nullable=false)
    public TipoVehiculo getTipoVehiculo() {
        return this.tipoVehiculo;
    }

As you can see in the name i removed all the Uppercases for lower, and since MySQL is not case sensitive its the same thing, even though in the table all its attributes use capital letters in it. This happens in all the clases where the name in the @joincolumn. Making hibernate create the correct query so it can by executed correctly:

SELECT 
    vehiculo0_.idvehiculo AS idvehicu1_25_,
    vehiculo0_.capacidad AS capacida2_25_,
    vehiculo0_.matricula AS matricul3_25_,
    vehiculo0_.tipo_vehiculo_idtipovehiculo AS tipo_veh5_25_,
    vehiculo0_.vacante AS vacante4_25_
FROM
    vehiculo vehiculo0_