如何在drools中增加对象字段

public class Person {
    private String name;
    private int age;

    // 构造函数、getter和setter方法等
}

package com.example.rules

import com.example.model.Person

rule "Age Rule"
when
    $person: Person(age < 18)
then
    System.out.println($person.getName() + " is underage.");
end

import org.kie.api.KieServices;
import org.kie.api.runtime.KieContainer;
import org.kie.api.runtime.KieSession;

public class DroolsExample {
    public static void main(String[] args) {
        // 创建KieServices实例
        KieServices kieServices = KieServices.Factory.get();

        // 创建KieContainer实例，加载规则文件
        KieContainer kieContainer = kieServices.getKieClasspathContainer();

        // 创建KieSession实例，用于执行规则
        KieSession kieSession = kieContainer.newKieSession();

        // 创建Person对象
        Person person = new Person("John", 20);

        // 将Person对象插入到KieSession中
        kieSession.insert(person);

        // 执行规则
        kieSession.fireAllRules();

        // 关闭KieSession
        kieSession.dispose();
    }
}