I am getting below given validation exception while sending http request from Postman to test Rest API.

2024-08-10T21:52:10.773+05:30 ERROR 24976 --- [validate-barcode] [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: org.springframework.transaction.TransactionSystemException: Could not commit JPA transaction] with root cause

jakarta.validation.ConstraintViolationException: Validation failed for classes [com.validate.validate_barcode.entity.Product] during persist time for groups [jakarta.validation.groups.Default, ]
List of constraint violations:[
ConstraintViolationImpl{interpolatedMessage=’must not be null’, propertyPath=createdDate, rootBeanClass=class com.validate.validate_barcode.entity.Product, messageTemplate='{jakarta.validation.constraints.NotNull.message}’}
]
at org.hibernate.boot.beanvalidation.BeanValidationEventListener.validate(BeanValidationEventListener.java:151) ~[hibernate-core-6.5.2.Final.jar:6.5.2.Final]

In my bean class, I have two instance variable createdDate and lastModifiedDate to capture record creation and updating date in the database.

My model class is –

    @Entity
@Table(name = "product_master")
public class Product {

    // Primary ID which increments automatically when new entry is added into the
    // database
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    int id;

    @Column(name = "product_code")
    @NotNull
    private String productCode;
    
    @Column(name = "product_name")
    @NotNull
    private String productName;
    
    @CreatedDate
    @NotNull
    @Column(name = "created_at", nullable = false, updatable = false)
    private LocalDateTime createdDate;
    
    @LastModifiedDate
    @Column(name = "updated_at")
    private LocalDateTime lastModifiedDate;
    
}

Controller Class is –

    //Annotation
@RestController
@RequestMapping("/validateproduct")
public class ProductController {

    // Annotation
    @Autowired
    private ProductService productSerive;

    // Save operation
    //@PostMapping("/saveProduct")
    @RequestMapping(value = "/saveProduct", produces = "application/json")
    public Product saveProduct(@RequestBody Product product) {
        System.out.println("Post Mapping - saveProduct");
        System.out.println(product.toString());
        return productSerive.saveProduct(product);
    }

}

In Postmen, I am sending data in body and have selected Body -> raw in Postmen. And request data is –

{
    "productCode":"abc1234",
    "productName":"ABCDEFG"
}

I explored some of the article to save created_at and updated_at, and I added @CreatedDate and @LastModifiedDate annotation.

pom.xml is –

<dependencies>
    
        <dependency> 
            <groupId>org.springframework.boot</groupId> 
            <artifactId>spring-boot-starter-validation</artifactId> 
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

Is here anything wrong, I am doing?