如何在 Java 中使用 Gson 实现自定义 JSON 序列化?
javajsonobject oriented programmingprogramming
如果我们需要一种方法将 java 对象转换为 JSON,Gson 库提供了一种指定自定义序列化器的方法,方法是使用 GsonBuilder 注册自定义序列化器。我们可以通过重写 com.google.gson.JsonSerializer 类的 serialize() 方法来创建自定义序列化器。
在下面的示例中,实现了 JSON 的自定义序列化。
示例
import java.lang.reflect.Type; import com.google.gson.*; public class CustomJSONSerializerTest { public static void main(String[] args) { Gson gson = new GsonBuilder().registerTypeAdapter(Password.class, new PasswordSerializer()) .setPrettyPrinting().create(); Student student = new Student("Adithya", "Jai", 25, "Chennai"); student.setPassword(new Password("admin@123")); System.out.println(gson.toJson(student)); } } class PasswordSerializer implements JsonSerializer { @Override public JsonElement serialize(Password src, Type typeOfSrc, JsonSerializationContext context) { return new JsonPrimitive(new StringBuffer(src.getPassword()).toString()); } } // Student classclass Student { private String firstName; private String lastName; private int age; private String address; private Password password; public Student(String firstName, String lastName, int age, String address) { super(); this.firstName = firstName; this.lastName = lastName; this.age = age; this.address = address; } public String getFirstName() { return firstName; } public void setFirstName(String firstName) { this.firstName = firstName; } public String getLastName() { return lastName; } public void setLastName(String lastName) { this.lastName = lastName; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public Password getPassword() { return password; } public void setPassword(Password password) { this.password = password; } public String toString() { return "Student[ " + "firstName = " + firstName + ", lastName = " + lastName + ", age = " + age + ", address = " + address + " ]"; } } // Password classclass Password { private String password; public Password(String password) { super(); this.password = password; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } }
输出
{ "firstName": "Adithya", "lastName": "Jai", "age": 25, "address": "Chennai", "password": "admin@123" }