Could not set field value by reflection

I have a problem with a many to many relationship. The tables are: ingredient and nutional value. I created a table of relations between the 2 entities, in which there are the external keys of ingredient and nutrional value (which form the compound key) and some attributes.

Class JoinedNutrionalValueIngredient:

import lombok.Data;
import javax.persistence.*;
import javax.validation.constraints.NotNull;

@Entity @Data
public class JoinedNutrionalValueIngredient implements Serializable {

    private NutrionalValueIngredientId id;

    @ManyToOne(fetch= FetchType.LAZY)
    private Ingredient ingredient;

    private NutrionalValue nutrionalValue;

    String matrixUnit;

    int value;

    String valueType;

Class NutrionalValueIngredientId:

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

public class NutrionalValueIngredientId implements Serializable{

    @Column(name = "ingredient_id")
    private Long ingredient_id;

    @Column(name = "nutrional_value_id")
    private Long nutrional_value_id;

    public NutrionalValueIngredientId() {
    public NutrionalValueIngredientId(Long ingredient, Long nutrionalValue){
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass())
            return false;
        NutrionalValueIngredientId that = (NutrionalValueIngredientId) o;
        return Objects.equals(ingredient_id, that.ingredient_id) &&
                    Objects.equals(nutrional_value_id, that.nutrional_value_id);
    public int hashCode() {
        return Objects.hash(ingredient_id, nutrional_value_id);

When I try to insert a new field inside the relationship table I get this error:

  "timestamp": 1542653896247,
  "status": 500,
  "error": "Internal Server Error",
  "message": "Could not set field value [1] value by reflection : [class com.whateat.reciper.model.NutrionalValueIngredientId.ingredient_id] setter of com.whateat.reciper.model.NutrionalValueIngredientId.ingredient_id; nested exception is org.hibernate.PropertyAccessException: Could not set field value [1] value by reflection : [class com.whateat.reciper.model.NutrionalValueIngredientId.ingredient_id] setter of com.whateat.reciper.model.NutrionalValueIngredientId.ingredient_id",
  "path": "/v1/joinedNutrionalValueIngredients"

Edit: I added constructor and annotation @Getter and @Setter, but I have the same error.

class NutritionalValue:

public class NutrionalValue implements Serializable {

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

    private String name;

    private String unit;

    private String source;

    @JoinColumn(name = "category_id")
    private NutrionalValueCategory category;

    @OneToMany(mappedBy = "nutrionalValue")
    private Set<JoinedNutrionalValueIngredient> joined = new HashSet<JoinedNutrionalValueIngredient>();


edit: after Debopam’s answer, this error came out.

  "timestamp": 1542657216244,
  "status": 500,
  "error": "Internal Server Error",
  "message": "null id generated for:class com.whateat.reciper.model.JoinedNutrionalValueIngredient; nested exception is null id generated for:class com.whateat.reciper.model.JoinedNutrionalValueIngredient",
  "path": "/v1/joinedNutrionalValueIngredients"


Change the variable Names as below

Long ingredient_id to Long ingredientid nutrional_value_id to nutrionalvalueid


  @Column(name = "ingredient_id")
  Long ingredient_id;


@Column(name = "ingredient_id")
Long ingredientid;

Then generate getter setter for all the fields. Hibernate is unable to set the fields because there is no public getter/setter.

Leave a Reply

Your email address will not be published. Required fields are marked *