Understand the technical principles of the Jersey JSON framework and its application scenarios in the Java class library
Understand the technical principles of the Jersey JSON framework and its application scenarios in the Java class library
Overview:
Jersey is a Java -based open source framework to develop the restful web service.It provides a simple and powerful way to build and release Web services, and provides local support for JSON (JavaScript Object Notification).This article will introduce the basic concepts, technical principles of the Jersey JSON framework, and application scenarios in the Java class library.
Technical principle:
The Jersey JSON framework is based on the Jackson JSON library. By using the JSON processing function provided by Jackson, Jersey can quickly and efficiently process JSON data in the Java class library.The Jackson library can convert the Java object into a string in JSON format, or the string of the JSON format as the Java object.
In Jersey, we can return the Java class to JSON to the client directly as a JSON response, or they can also receive and resolve from the JSON request into the Java object.This is achieved by marking the Java class and methods by using annotations.For example, use the `@path` annotation to define the RESTFUL resource path, and use the@get` annotation to mark the http get request.When returning to response, you can use the `@produces (MediaType.application_json)` `Note tells Jersey to sequence the Java object to JSON format.
Application scenario:
The Jersey Json framework has a variety of application scenarios in the Java library.Here are some common application scenarios:
1. RESTFUL Web service: Jersey provides the function of constructing and publishing the RESTFUL Web service. Among them, JSON is a commonly used data format.You can use the Jersey JSON framework to convert the Java object to the JSON string and return it to the client as a Web service response.
2. End and back -end separation: In the architecture of separation of the front and back end, the RESTFUL API is usually provided for the front -end call.Through the Jersey JSON framework, the back end can directly convert the Java object to the data in JSON format to the front end.
3. Data exchange and storage: In Java applications, you can use the Jersey JSON framework to save the Java object as a JSON format file.At the same time, you can also read data from the JSON file and analyze it as a Java object.
4. Mobile application development: The Jersey JSON framework can be used to develop the back -end service of mobile applications.By converting the Java object to JSON format, the data can be easily transmitted to the mobile device.
Example code:
The following is a simple example code that shows the application scenario of the Jersey JSON framework in the Java library:
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
@Path("/student")
public class StudentResource {
// Get student information
@GET
@Produces(MediaType.APPLICATION_JSON)
public Student getStudent() {
// Get student information from the database or other data source
Student Student = New Student ("Zhang San", 18, "Computer Science");
return student;
}
}
public class Student {
private String name;
private int age;
private String major;
// omit the creation function and getter/setter method
// Note: The default non -constructor function is necessary
// Example Student Object Create
Student Student = New Student ("Zhang San", 18, "Computer Science");
// Convert the student object to a JSON string
ObjectMapper mapper = new ObjectMapper();
String studentJson = mapper.writeValueAsString(student);
// Analyze the JSON string as a Student object
Student parsedStudent = mapper.readValue(studentJson, Student.class);
}
This example code shows how to use the Jersey Json framework to convert an instance of the `Student` class into a JSON string, and return it to the client as a response in the web service.The client can use HTTP GET to request student information and obtain response through the JSON format.
Summarize:
The Jersey JSON framework provides a convenient and flexible way to process JSON data.Based on the Jackson library, it simplifies the processing process of JSON data by using the annotation marker Java class and methods.By understanding the technical principles of the Jersey JSON framework and application scenarios in the Java class library, we can better use it to develop and deploy the RESTFUL Web service and process and exchange JSON data.
