How to use the Valdr Bean Validation framework in the Java library to improve the accuracy of data
How to use the Valdr Bean Validation framework in the Java library to improve the accuracy of data
Overview:
Valdr is a Bean verification framework for front -end data verification. It provides a simple and flexible way to define and perform data verification rules to ensure the accuracy and consistency of the data.This article will introduce how to use the Valdr framework in the Java library to improve the accuracy of the data and provide relevant programming code and configuration examples.
Step 1: Configure VALDR dependencies
First, in the pom.xml file of the Java class library, add the Valdr framework and the configuration of related dependencies.For example, use the following code:
<dependency>
<groupId>com.github.valdr</groupId>
<artifactId>valdr</artifactId>
<version>1.0.0</version>
</dependency>
Step 2: Define the data model in the Java class
The data model is then defined in the Java class, including fields that need to be verified and corresponding verification rules.For example, suppose we have a class called User and want to verify its name and age field.Use the following code to define the user class:
import com.github.valdr.ValdrBeanValidation;
@ValdrBeanValidation
public class User {
private String name;
private int age;
// getters and setters
}
Step 3: Define the verification rules
Next, we need to define verification rules in the User class.This can be completed by using the annotations provided by Valdr.In this example, we use the rules to define the rules with the annotations of `@SupportedValidationRule`, and use the@Valid` annotation to specify the field to verify.For example, the following code shows how to define a rule, requiring the name field to not be a empty string:
import com.github.valdr.constraint.MinSize;
import com.github.valdr.constraint.NotBlank;
import com.github.valdr.constraint.SupportedValidationRule;
@SupportedValidationRule
public @interface UserValidationRules {
@Notblank (Message = "Name cannot be empty")
String name();
}
Step 4: Application Verification Rules
Finally, where the data needs to be verified, we can use the VALDR framework to apply the definition of verification rules.For example, the following code shows how to use Valdr in Controller to verify the User object:
import com.github.valdr.Valdr;
@RestController
public class UserController {
private Valdr valdr = new Valdr();
@Autowired
private UserValidator userValidator;
@PostMapping("/user")
public ResponseEntity<String> createUser(@RequestBody User user) {
Set <constraintviolation <user >> violaservations = uservalidator.validate (user); // Use verification rules defined in the UserValidator class
if (!violations.isEmpty()) {
StringBuilder errorMessage = new StringBuilder();
for (ConstraintViolation<User> violation : violations) {
errorMessage.append(violation.getMessage()).append("
");
}
return ResponseEntity.badRequest().body(errorMessage.toString());
}
// Data verification passes, execute saving operation
// ...
Return Responsentity.ok ("Successful user creation");
}
}
Step 5: Create the verification device
In addition to defining verification rules, we also need to create a verification class to actively perform data verification.For example, the following code shows how to create a verification device called UserValidator:
import com.github.valdr.Validator;
public class UserValidator extends Validator<User> {
public UserValidator() {
super(User.class);
}
}
After completing the above steps, we successfully use the Valdr Bean Validation framework in the Java library to improve the accuracy of data.VALDR provides a simple and flexible way to define and execute front -end data verification rules to ensure the accuracy and consistency of the data.
Remarks: The above code example uses the Spring framework as a demonstration, but the Valdr framework is compatible with any commonly used Java library.
I hope this article is helpful to you how to use the Valdr framework in the Java class library!
