Gson 简明教程
Gson - Object Serialization
让我们将 Java 对象序列化到 Json 文件，然后读取该 Json 文件以返回该对象。在此示例中，我们创建了 Student 类。我们将创建一个 student.json 文件，该文件将有一个 json 的 Student 对象表示形式。
Let’s serialize a Java object to a Json file and then read that Json file to get the object back. In this example, we’ve created a Student class. We’ll create a student.json file which will have a json representation of Student object.
Example
在 C:>GSON_WORKSPACE 中创建名为 GsonTester 的 Java 类文件。
Create a Java class file named GsonTester in C:\>GSON_WORKSPACE.
File - GsonTester.java
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+ " ]";
}
}