Analysis of the technical principle of the core framework in the Java class library
Analysis of the technical principle of the core framework in the Java class library
In Java development, verification is a very important link to ensure the correctness and security of the data.The core framework of the verification in the Java library provides a convenient way to verify, and the input data is verified to ensure that it meets the expected requirements.
The technical principles of verifying the core framework mainly include the following aspects:
1. Verification annotation: The verification core framework in the Java class library uses the method of annotation to identify the field or method that requires verification.By adding a specific verification annotation to the target field or method, the verification conditions that the field or method needs to be met can be specified.
For example, using @Notnull annotations to identify a field cannot be empty, and use @Size annotation to identify the length range of a field.These annotations are provided by the core framework of verification and provide a series of attributes for specifying specific verification conditions.
public class Person {
@NotNull
private String name;
@Min(18)
private int age;
// omit other fields and methods
}
2. Verifying device: Verification in the core framework is a component of the actual execution of the verification operation.The verification device verifies the target field according to the verification conditions specified in the verification annotation.
The verification device can be predetermined or customized.The predetermined verification device generally contains commonly used verification logic, such as verification of string length, digital range verification, etc.If you need more complicated verification logic, you can customize the verification device.
public class CustomValidator implements ConstraintValidator<CustomValidation, String> {
@Override
public boolean isValid(String value, ConstraintValidatorContext context) {
// Customized verification logic
}
// omit other methods
}
3. Verify factory: Verify the factory provides the instance and management functions of the verification device.In the verification core framework, the factory can be obtained by verifying the factory to obtain an instance of the specified verification device and performs verification operations.
Verify factory is usually a single -case or tool class, which provides the obtaining and management functions of the verification device through static methods or instance methods.Different verification factory instances can be created as needed to manage different verifications.
public class ValidatorFactory {
private static final ValidatorFactory instance = new ValidatorFactory();
public static ValidatorFactory getInstance() {
return instance;
}
public Validator getValidator(Class<?> clazz) {
// Obtain the corresponding authenticator instance according to the class
}
// omit other methods
}
4. Verification results: Verify the core framework that can return the verification results and inform the verification of the success or failure of the verification.The verification results can provide detailed failure information for facilitating and repairing problems.
Verification results are usually returned in the form of objects, including verification success, failure information, and other related information.You can process the verification results as needed, such as displaying the failure information to the user or recorded in the log.
public class ValidationResult {
private boolean valid;
private List<String> errorMessages;
// omit the constructive method and other methods
}
In summary, the technical principles of verifying the core framework in the Java library include the cooperation of components such as verification annotations, verifications, verification factories, and verification results.By using these components, it can easily realize the verification of input data and improve the robustness and maintenance of the code.
