Gson對象序列化

我們將一個Java對象序列化為一個Json檔，然後讀取該Json檔以獲取對象。 在這個例子中，創建一個Student類。 然後將對象列化後存儲在student.json檔中，該檔將具有Student對象的json表示形式。

示例

在中創建一個名為GsonTester的Java類檔，參考以下代碼 -

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

public class GsonTester {
   public static void main(String args[]) {
      GsonTester tester = new GsonTester();
      try {
         Student student = new Student();
         student.setAge(10);
         student.setName("Mahesh");
         tester.writeJSON(student);
         Student student1 = tester.readJSON();
         System.out.println(student1);
      }
      catch(FileNotFoundException e) {
         e.printStackTrace();
      }
      catch(IOException e) {
         e.printStackTrace();
      }
   }
   private void writeJSON(Student student) throws IOException {
      GsonBuilder builder = new GsonBuilder();
      Gson gson = builder.create();
      FileWriter writer = new FileWriter("student.json");
      writer.write(gson.toJson(student));
      writer.close();
   }
   private Student readJSON() throws FileNotFoundException {
      GsonBuilder builder = new GsonBuilder();
      Gson gson = builder.create();
      BufferedReader bufferedReader = new BufferedReader(
         new FileReader("student.json"));

      Student student = gson.fromJson(bufferedReader, Student.class);
      return student;
   }
}
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+ " ]";
   }
}

執行上面示例代碼，得到以下結果 -

Student [ name: Mahesh, age: 10 ]