Gson - 序列化内部类
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
让我们看一个带有内部类的类序列化/反序列化的示例。在 C:\>GSON_WORKSPACE 中创建名为GsonTester的 Java 类文件。
文件 - 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,如下所示 -
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
让我们看一下使用静态内部类进行类的序列化/反序列化的示例。在 C:\>GSON_WORKSPACE 中创建名为 GsonTester 的 Java 类文件。
文件 - 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,如下所示 -
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