gson 對(duì)象數(shù)據(jù)綁定

對(duì)象數(shù)據(jù)綁定是指將 json 映射到任何 java 對(duì)象。

//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);

1. 范例

讓我們看看對(duì)象數(shù)據(jù)的綁定。在這里，我們將 java object 直接映射到 json，反之亦然。

在c:>gson_workspace中創(chuàng)建名為 gsontester 的java類文件。

文件：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+ " ]";
   }  
}

2. 驗(yàn)證結(jié)果

使用 javac 編譯器編譯類如下：

c:\gson_workspace>javac gsontester.java

現(xiàn)在運(yùn)行 gsontester 查看結(jié)果：

c:\gson_workspace>java gsontester

驗(yàn)證輸出。

{"name":"mahesh","age":10}
student [ name: mahesh, age: 10 ]