Gson 简明教程

Gson - Object Data Binding

对象数据绑定是指 JSON 与任何 JAVA 对象之间的映射。

Object data binding refers to mapping of JSON to any JAVA Object.

//Create a Gson instance
Gson gson = new Gson();

//map Student object to JSON content
String jsonString = gson.toJson(student);

//map JSON content to Student object
Student student1 = gson.fromJson(jsonString, Student.class);

Example

让我们看看对象数据绑定在实际使用中的情况。在这里，我们将直接将 JAVA 对象映射到 JSON，反之亦然。

Let’s see object data binding in action. Here we’ll map JAVA Object directly to JSON and vice versa.

在 C:\>GSON_WORKSPACE 创建一个名为 GsonTester 的 Java 类文件。

Create a Java class file named GsonTester in C:\>GSON_WORKSPACE.

File - GsonTester.java

import com.google.gson.Gson;

public class GsonTester {
   public static void main(String args[]) {

      Gson gson = new Gson();
      Student student = new Student();
      student.setAge(10);
      student.setName("Mahesh");

      String jsonString = gson.toJson(student);
      System.out.println(jsonString);

      Student student1 = gson.fromJson(jsonString, Student.class);
      System.out.println(student1);
   }
}

class Student {
   private String name;
   private int age;
   public Student(){}

   public String getName() {
      return name;
   }

   public void setName(String name) {
      this.name = name;
   }

   public int getAge() {
      return age;
   }

   public void setAge(int age) {
      this.age = age;
   }

   public String toString() {
      return "Student [ name: "+name+", age: "+ age+ " ]";
   }
}

Verify the result

使用以下 javac 编译器编译类：

Compile the classes using javac compiler as follows −

C:\GSON_WORKSPACE>javac GsonTester.java

现在运行 GsonTester 以查看结果 −

Now run the GsonTester to see the result −

C:\GSON_WORKSPACE>java GsonTester

验证输出。

Verify the output.

{"name":"Mahesh","age":10}
Student [ name: Mahesh, age: 10 ]