如何在 Java 中使用 Gson 庫使用 @Until 註解?
@Until 註解 可與 GsonBuilder 類的 setVersion() 方法一起使用。此註解可應用於 Java 類的欄位,並接受浮點數作為引數。此引數表示已序列化的欄位的版本號。@Until 註解可管理網路服務中 JSON 類的版本控制。
語法
@Documented @Retention(value=RUNTIME) @Target(value={FIELD,TYPE}) public @interface Until
示例
import com.google.gson.annotations.Until; import com.google.gson.Gson; import com.google.gson.GsonBuilder; public class GsonUntilAnnotationTest { public static void main(String[] args) { Employee emp = new Employee(); emp.setEmployeeName("Adithya"); emp.setEmployeeId(115); emp.setEmployeeTechnology("Python"); emp.setEmploeeAddress("Pune"); System.out.println("Using version 0.5"); GsonBuilder gsonBuilder = new GsonBuilder(); Gson gson = gsonBuilder.setPrettyPrinting().setVersion(0.5).create(); String jsonString = gson.toJson(emp); System.out.println(jsonString); System.out.println("Using version 1.0"); gsonBuilder = new GsonBuilder(); gson = gsonBuilder.setPrettyPrinting().setVersion(1.0).create(); jsonString = gson.toJson(emp); System.out.println(jsonString); System.out.println("Using version 1.1"); gsonBuilder = new GsonBuilder(); gson = gsonBuilder.setPrettyPrinting().setVersion(1.1).create(); jsonString = gson.toJson(emp); System.out.println(jsonString); } } // Employee class class Employee { private String empName; private int empId; @Until(1.1) private String empTech; @Until(1.1) private String empAddress; public String getEmployeeName() { return empName; } public void setEmployeeName(String empName) { this.empName = empName; } public int getEmployeeId() { return empId; } public void setEmployeeId(int empId) { this.empId = empId; } public String getEmployeeTechnology() { return empTech; } public void setEmployeeTechnology(String empTech) { this.empTech = empTech; } public String getEmploeeAddress() { return empAddress; } public void setEmploeeAddress(String empAddress) { this.empAddress = empAddress; } }
輸出
Using version 0.5 { "empName": "Adithya", "empId": 115, "empTech": "Python", "empAddress": "Pune" } Using version 1.0 { "empName": "Adithya", "empId": 115, "empTech": "Python", "empAddress": "Pune" } Using version 1.1 { "empName": "Adithya", "empId": 115 }
廣告