Java toString()使用反射？

import java.lang.reflect.Field;

public class MyClass {
    private int id;
    private String name;

    public MyClass(int id, String name) {
        this.id = id;
        this.name = name;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("MyClass{");

        try {
            for (Field field : this.getClass().getDeclaredFields()) {
                field.setAccessible(true);
                sb.append(field.getName()).append("=").append(field.get(this)).append(", ");
            }
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }

        if (sb.length() > 1) {
            sb.setLength(sb.length() - 2);
        }

        sb.append("}");

        return sb.toString();
    }

    public static void main(String[] args) {
        MyClass obj = new MyClass(1, "John");
        System.out.println(obj.toString());
    }
}

MyClass{id=1, name=John}