The parameter validation feature is implemented based on JSR303. Users only need to specify validation annotations from the JSR303 standard and implement validation through a declared filter.
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>1.0.0.GA</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>4.2.0.Final</version>
</dependency>
The server addresses various interface parameter validation issues when providing interface services externally.
Reference Case https://github.com/apache/dubbo-samples/tree/master/dubbo-samples-validation
import java.io.Serializable;
import java.util.Date;
import javax.validation.constraints.Future;
import javax.validation.constraints.Max;
import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Past;
import javax.validation.constraints.Pattern;
import javax.validation.constraints.Size;
public class ValidationParameter implements Serializable {
private static final long serialVersionUID = 7158911668568000392L;
@NotNull // Cannot be null
@Size(min = 1, max = 20) // Length or size range
private String name;
@NotNull(groups = ValidationService.Save.class) // Cannot be null when saving, can be null when updating, indicating no update to this field
@Pattern(regexp = "^\\s*\\w+(?:\\.{0,1}[\\w-]+)*@[a-zA-Z0-9]+(?:[-.][a-zA-Z0-9]+)*\\.[a-zA-Z]+\\s*$")
private String email;
@Min(18) // Minimum value
@Max(100) // Maximum value
private int age;
@Past // Must be a past date
private Date loginDate;
@Future // Must be a future date
private Date expiryDate;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public Date getLoginDate() {
return loginDate;
}
public void setLoginDate(Date loginDate) {
this.loginDate = loginDate;
}
public Date getExpiryDate() {
return expiryDate;
}
public void setExpiryDate(Date expiryDate) {
this.expiryDate = expiryDate;
}
}
public interface ValidationService { // Default can differentiate validation scenarios by service interface, e.g., @NotNull(groups = ValidationService.class)
@interface Save{} // Interface name same as method, capitalized first letter, used to differentiate validation scenarios, e.g., @NotNull(groups = ValidationService.Save.class), optional
void save(ValidationParameter parameter);
void update(ValidationParameter parameter);
}
import javax.validation.GroupSequence;
public interface ValidationService {
@GroupSequence(Update.class) // Validate Update group rules simultaneously
@interface Save{}
void save(ValidationParameter parameter);
@interface Update{}
void update(ValidationParameter parameter);
}
import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;
public interface ValidationService {
void save(@NotNull ValidationParameter parameter); // Validate parameter is not null
void delete(@Min(1) int id); // Directly validate basic type parameter
}
<dubbo:reference id="validationService" interface="org.apache.dubbo.examples.validation.api.ValidationService" validation="true" />
<dubbo:service interface="org.apache.dubbo.examples.validation.api.ValidationService" ref="validationService" validation="true" />
Dubbo supports hibernate-validator version <=6.x by default. If using hibernate-validator version 7.x, declare the validation parameter as jvalidationNew.
import javax.validation.ConstraintViolationException;
import javax.validation.ConstraintViolationException;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.apache.dubbo.examples.validation.api.ValidationParameter;
import org.apache.dubbo.examples.validation.api.ValidationService;
import org.apache.dubbo.rpc.RpcException;
public class ValidationConsumer {
public static void main(String[] args) throws Exception {
String config = ValidationConsumer.class.getPackage().getName().replace('.', '/') + "/validation-consumer.xml";
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(config);
context.start();
ValidationService validationService = (ValidationService)context.getBean("validationService");
// Error
try {
parameter = new ValidationParameter();
validationService.save(parameter);
System.out.println("Validation ERROR");
} catch (RpcException e) { // Throws RpcException
ConstraintViolationException ve = (ConstraintViolationException) e.getCause(); // Inside is a nested ConstraintViolationException
Set<ConstraintViolation<?>> violations = ve.getConstraintViolations(); // Can get a collection of detailed validation error information
System.out.println(violations);
}
}
}
Validation methods are extensible. See the developer manual for validation extensions for more information.