I have an error when accessing a field with JPA. How do I solve this?

Question

When trying to insert values into my table, i get this error

org.hibernate.property.access.spi.PropertyAccessException: Error accessing 
field [private int com.app.demo.model.Customer.id] by reflection for 
persistent property [com.app.demo.model.Customer#id] : 
com.app.demo.model.Customer@6d1c6e1e
javax.persistence.PersistenceException: 
org.hibernate.property.access.spi.PropertyAccessException: Error accessing 
field [private int com.app.demo.model.Customer.id] by reflection for 
persistent property [com.app.demo.model.Customer#id] : com.app.demo.model.Customer@6d1c6e1e

This is my customer table. I am using MySql Workbench, and I am trying to insert my values into here.

And i am using using this class to insert values into the table

@Entity
@Table(name="customer")
public class Customer {

@Id
@GeneratedValue
@Column(name = "customer_id", unique = true, nullable = false)
private int id;
@Column(name="first_name")
private String firstName;
@Column(name="last_name")
private String lastName;
@Column(name="street_address")
private String address;
@Column(name="city")
private String city;
@Column(name="state")
private String state;
@Column(name="zip_code")
private String zipcode;
@Column(name="email")
private String email;
@Column(name="paypal_email")
private String paypalEmail;


// getters and setters

And this is how I am inserting values into my table

// Set customer values
Customer valuedCustomer = new Customer();

valuedCustomer.setFirstName(firstName);
valuedCustomer.setLastName(lastName);
valuedCustomer.setAddress(address);
valuedCustomer.setCity(city);
valuedCustomer.setState(state);
valuedCustomer.setZipcode(zip);
valuedCustomer.setEmail(email);

// insert customer info into the customer table
EntityManagerFactory emf = Persistence.createEntityManagerFactory("pu");

EntityManager em = emf.createEntityManager();

em.getTransaction().begin();
em.persist(valuedCustomer);
em.getTransaction().commit();

EDIT:

My customer table

My user table (this table i did the unit test on)

@ScaryWombat Yes i do. I was doing some unit testing, and it seems like my column for id in my sql table cant be `customer_id` it has to be `id` in order for it to work. — Tony, Mar 12 '19 at 04:24
Check this out, seems like column name annotations could be being ignored without the right settings : https://stackoverflow.com/questions/25283198/spring-boot-jpa-column-name-annotation-ignored — racraman, Mar 12 '19 at 04:37
@racraman this is a weird problem. When I do unit tests, the values get inserted in my table. Since i am doing all of this inserting in a controller, is this the reason for the error? — Tony, Mar 12 '19 at 04:44
Can you do "show columns" for both your actual customer table, and also the other temporary table that works (where you've renamed the column from "customer_id" to "id"). I'm guessing that you've declared the latter "not null" ? :) — racraman, Mar 12 '19 at 05:31
hey @racraman, i added pictures to the post. I am not sure why this isn't working on either one when i use this inside my controller. The unit test works fine. ): — Tony, Mar 12 '19 at 06:27
Thanks @Tony - drats, so it's not "not null". PropertyAccessException used to be thrown when a nullable column was mapped to a primitive, so thought that might still be the case, and be the case here - but you've got them not null, so should be good. — racraman, Mar 12 '19 at 06:44

score 2 · Answer 1 · answered Mar 12 '19 at 05:03

2

try using AUTO or IDENTITY policy. like:

@GeneratedValue(strategy = GenerationType.IDENTITY)

answered Mar 12 '19 at 05:03

PatrickChen

1,194
9
17

score 1 · Answer 2 · answered Mar 12 '19 at 05:13

Here is the ID field definition in your entity class

@Id
@GeneratedValue
@Column(name = "customer_id", unique = true, nullable = false)
private int id;

Here ID field is unique and not null. So you must have to provide the data on ID field during insertion.

First of all, using annotations as our configure method is just a convenient method instead of coping the endless XML configuration file.

The @Idannotation is inherited from javax.persistence.Id， indicating the member field below is the primary key of current entity. Hence your Hibernate and spring framework as well as you can do some reflect works based on this annotation. for details please check javadoc for Id

The @GeneratedValue annotation is to configure the way of increment of the specified column(field).

For example when using Mysql, you may specify auto_increment in the definition of table to make it self-incremental, and then use

@GeneratedValue(strategy = GenerationType.IDENTITY)

I replaced `@GeneratedValue` with `@GeneratedValue(strategy=GenerationType.IDENTITY)`. I also replaced `@Column(name = "customer_id", unique = true, nullable = false)` with just `@Column(name = "customer_id")` and it still gives the same error. Do you have any other suggestions? — Tony, Mar 12 '19 at 06:35

I have an error when accessing a field with JPA. How do I solve this?

2 Answers2