反射-通過反射寫一個通用的設定某個物件的某個屬性為指定的值

package cn.itcast.test;

import java.lang.reflect.Field;

public class Tool {
	public void setProperty(Object obj, String propertyName, Object value)
			throws NoSuchFieldException, SecurityException,
			IllegalArgumentException, IllegalAccessException {
		// 根據物件獲取位元組碼檔案物件
		Class c = obj.getClass();
		// 獲取該物件的propertyName成員變數
		Field field = c.getDeclaredField(propertyName);
		// 取消訪問檢查
		field.setAccessible(true);
		// 給物件的成員變數賦值為指定的值
		field.set(obj, value);
	}
}

package cn.itcast.test;

public class ToolDemo {
	public static void main(String[] args) throws NoSuchFieldException,
			SecurityException, IllegalArgumentException, IllegalAccessException {
		Person p = new Person();
		Tool t = new Tool();
		t.setProperty(p, "name", "林青霞");
		t.setProperty(p, "age", 27);
		System.out.println(p);
		System.out.println("-----------");

		Dog d = new Dog();
		t.setProperty(d, "sex", '雄');
		t.setProperty(d, "price", 12.34f);
		System.out.println(d);
	}
}

class Dog {
	char sex;
	float price;

	@Override
	public String toString() {
		return sex + "---" + price;
	}
}

class Person {
	private String name;
	public int age;

	@Override
	public String toString() {
		return name + "---" + age;
	}
}