序列化内部类（Serializing Inner Classes）

在本章中，我们将解释具有内部类的类的序列化/反序列化。

嵌套的内部类示例

Student student = new Student(); 
student.setRollNo(1); 
Student.Name name = student.new Name(); 
name.firstName = "Mahesh"; 
name.lastName = "Kumar"; 
student.setName(name); 
//serialize inner class object 
String nameString = gson.toJson(name); 
System.out.println(nameString); 
//deserialize inner class object   
name = gson.fromJson(nameString,Student.Name.class); 
System.out.println(name.getClass()); 

例子 (Example)

让我们看一个带有内部类的类的序列化/反序列化的示例。 在C:\“GSON_WORKSPACE中创建名为GsonTester的Java类文件。

File: GsonTester.java

import com.google.gson.Gson;  
public class GsonTester { 
   public static void main(String args[]) { 
      Student student = new Student();  
      student.setRollNo(1); 
      Student.Name name = student.new Name(); 
      name.firstName = "Mahesh"; 
      name.lastName = "Kumar"; 
      student.setName(name); 
      Gson gson = new Gson(); 
      String jsonString = gson.toJson(student); 
      System.out.println(jsonString);  
      student = gson.fromJson(jsonString, Student.class);  
      System.out.println("Roll No: "+ student.getRollNo()); 
      System.out.println("First Name: "+ student.getName().firstName); 
      System.out.println("Last Name: "+ student.getName().lastName);  
      String nameString = gson.toJson(name); 
      System.out.println(nameString);  
      name = gson.fromJson(nameString,Student.Name.class); 
      System.out.println(name.getClass()); 
      System.out.println("First Name: "+ name.firstName); 
      System.out.println("Last Name: "+ name.lastName); 
   }      
}  
class Student { 
   private int rollNo; 
   private Name name;  
   public int getRollNo() { 
      return rollNo; 
   }  
   public void setRollNo(int rollNo) { 
      this.rollNo = rollNo; 
   }  
   public Name getName() { 
      return name; 
   } 
   public void setName(Name name) { 
      this.name = name; 
   } 
   class Name { 
      public String firstName; 
      public String lastName; 
   } 
} 

验证结果

使用javac编译器编译类如下 -

C:\GSON_WORKSPACE>javac GsonTester.java

现在运行GsonTester查看结果 -

C:\GSON_WORKSPACE>java GsonTester

验证输出。

{"rollNo":1,"name":{"firstName":"Mahesh","lastName":"Kumar"}} 
Roll No: 1 
First Name: Mahesh 
Last Name: Kumar 
{"firstName":"Mahesh","lastName":"Kumar"} 
class Student$Name 
First Name: Mahesh 
Last Name: Kumar

嵌套静态内部类示例

Student student = new Student(); 
student.setRollNo(1); 
Student.Name name = new Student.Name(); 
name.firstName = "Mahesh"; 
name.lastName = "Kumar"; 
student.setName(name); 
//serialize static inner class object 
String nameString = gson.toJson(name); 
System.out.println(nameString); 
//deserialize static inner class object   
name = gson.fromJson(nameString,Student.Name.class); 
System.out.println(name.getClass()); 

例子 (Example)

让我们看一个带有静态内部类的类的序列化/反序列化的示例。 在C:\> GSON_WORKSPACE中创建名为GsonTester的Java类文件。

File: GsonTester.java

import com.google.gson.Gson;  
public class GsonTester { 
   public static void main(String args[]) { 
      Student student = new Student();  
      student.setRollNo(1); 
      Student.Name name = new Student.Name(); 
      name.firstName = "Mahesh"; 
      name.lastName = "Kumar";  
      student.setName(name); 
      Gson gson = new Gson(); 
      String jsonString = gson.toJson(student); 
      System.out.println(jsonString);  
      student = gson.fromJson(jsonString, Student.class);  
      System.out.println("Roll No: "+ student.getRollNo()); 
      System.out.println("First Name: "+ student.getName().firstName); 
      System.out.println("Last Name: "+ student.getName().lastName);  
      String nameString = gson.toJson(name); 
      System.out.println(nameString);  
      name = gson.fromJson(nameString,Student.Name.class); 
      System.out.println(name.getClass()); 
      System.out.println("First Name: "+ name.firstName); 
      System.out.println("Last Name: "+ name.lastName); 
   }      
}  
class Student { 
   private int rollNo; 
   private Name name;  
   public int getRollNo() { 
      return rollNo; 
   }  
   public void setRollNo(int rollNo) { 
      this.rollNo = rollNo; 
   }  
   public Name getName() { 
      return name; 
   }  
   public void setName(Name name) { 
      this.name = name; 
   } 
   static class Name { 
      public String firstName; 
      public String lastName; 
   } 
} 

验证结果

使用javac编译器编译类如下 -

C:\GSON_WORKSPACE>javac GsonTester.java 

现在运行GsonTester查看结果 -

C:\GSON_WORKSPACE>java GsonTester 

验证输出。

{"rollNo":1,"name":{"firstName":"Mahesh","lastName":"Kumar"}} 
Roll No: 1 
First Name: Mahesh 
Last Name: Kumar 
{"firstName":"Mahesh","lastName":"Kumar"} 
class Student$Name 
First Name: Mahesh 
Last Name: Kumar