Java 中使用 Jackson 支持 JSON 模式?
javajsonobject oriented programmingprogramming
JSON 模式是一种基于 JSON 的格式规范,用于定义 JSON 数据的结构。JsonSchema 类可以为给定应用程序需要哪些 JSON 数据以及如何与其交互提供契约。JsonSchema 可以定义 JSON 数据的验证、文档、超链接导航和交互控制。我们可以使用 JsonSchemaGenerator 的 generateSchema() 方法生成 JSON 模式,该类包装了 JSON 模式生成功能。
语法
public JsonSchema generateSchema(Class<T> type) throws com.fasterxml.jackson.databind.JsonMappingException
示例
import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.module.jsonSchema.JsonSchema; import com.fasterxml.jackson.module.jsonSchema.JsonSchemaGenerator; import java.util.List; public class JSONSchemaTest { public static void main(String[] args) throws JsonProcessingException { ObjectMapper jacksonObjectMapper = new ObjectMapper(); JsonSchemaGenerator schemaGen = new JsonSchemaGenerator(jacksonObjectMapper); JsonSchema schema = schemaGen.generateSchema(Person.class); String schemaString = jacksonObjectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(schema); System.out.println(schemaString); } } // Person class class Person { private String name; private int age; private List<String> courses; private Address address; public String getName() { return name; } public int getAge(){ return age; } public List<String> getCourse() { return courses; } public Address getAddress() { return address; } } // Address class class Address { private String firstLine; private String secondLine; private String thirdLine; public String getFirstLine() { return firstLine; } public String getSecondLine() { return secondLine; } public String getThirdLine() { return thirdLine; } }
输出
{ "type" : "object", "id" : "urn:jsonschema:Person", "properties" : { "name" : { "type" : "string" }, "age" : { "type" : "integer" }, "address" : { "type" : "object", "id" : "urn:jsonschema:Address", "properties" : { "firstLine" : { "type" : "string" }, "secondLine" : { "type" : "string" }, "thirdLine" : { "type" : "string" } } }, "course" : { "type" : "array", "items" : { "type" : "string" } } } }