The principle and characteristics of the Jersey Ext Bean Validation framework

Jersey Ext Bean Validation is a framework for data verification in the Java library.It is based on the Bean Validation specification of Java and provides the function of data verification in the Jersey framework. Jersey is a framework for building a restful web service, and data verification is one of the key links to ensure the legality and effectiveness of the input data.The main goal of Jersey Ext Bean Validation is to provide developers with simple and easy -to -use data verification functions to help developers improve code quality and security. The principle of Jersey Ext Bean Validation is to define data verification rules in the API interface and the corresponding POJO class through annotations, and then use the verification device provided by the framework to verify the transmitted data.When the interface receives the request, the framework will automatically bound the data in the request to the corresponding POJO object and verify the verification rules.If the verification fails, the corresponding error information will be returned so that developers can handle the corresponding processing according to the error message. The following is a simple example, demonstrating how to use Jersey Ext Bean Validation in Jersey for data verification. First of all, we need to add Jersey Ext Bean Validation to the POM.XML file: <dependencies> ... <dependency> <groupId>org.glassfish.jersey.ext</groupId> <artifactId>jersey-bean-validation</artifactId> <version>2.34</version> </dependency> ... </dependencies> Then, use the @valid annotation in the API interface to mark the parameters required for verification: @Path("/example") public class ExampleResource { ... @POST @Path("/add") public Response addUser(@Valid User user) { // Processing user adding logic ... return Response.ok().build(); } ... } In the above example, we define an adduser method that uses @Valid annotations in the method parameter to mark the User object to verify. Next, we need to define verification rules in the User class.We can use common annotations provided by the Bean Validation specifications, such as@notnull,@size, etc. public class User { @NotNull @Size(min = 2, max = 20) private String name; @NotNull @Email private String email; // omit other attributes and methods } In the above example, we define the two attributes of Name and Email, and use @Notnull and @size annotations for verification. When we send a request to the API, for example: http POST http://localhost:8080/example/add Content-Type: application/json { "name": "John", "email": "john@example.com" } If the data in the request meets the verification rules, the API will be executed normally.Otherwise, the API will return the corresponding verification error information, such as: http HTTP 400 Bad Request Content-Type: application/json { "errors": [ "name: size must be between 2 and 20", "email: must be a well-formed email address" ] } The above example demonstrates the basic principles and methods of use of the Jersey Ext Bean Validation framework.By using this framework, developers can easily define data verification rules and automatically perform data verification in the interface to improve the quality and security of the code.