在java中动态选择要更新的字段

import java.lang.reflect.Field;

public class UpdateFieldsExample {
    public static void main(String[] args) throws NoSuchFieldException, IllegalAccessException {
        // 获取要更新的对象
        User user = new User("Alice", 25);

        // 获取Class对象
        Class<?> clazz = user.getClass();

        // 获取要更新的字段名
        String fieldName = "name";

        // 获取Field对象
        Field field = clazz.getDeclaredField(fieldName);

        // 设置字段的访问权限为可访问
        field.setAccessible(true);

        // 更新字段的值
        field.set(user, "Bob");

        System.out.println(user.getName()); // 输出 "Bob"
    }
}

class User {
    private String name;
    private int age;

    public User(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }
}