利用反射实现一个管理对象信息的简单框架

看实现的效果：

然后运行我们的代码，它能够按照我们配置文件声明的类和属性去创造对应的实例

更改配置文件的信息：

对应的结果：

实现步骤：

首先通过Class类的**getResourceAsStream()**方法去获取一个文件的输入流

Properties properties = new Properties();
InputStream resourceAsStream = MySpring.class.getResourceAsStream(PROPRETIES_PATH);

首先通过Properties类来加载文件中的信息——包含类的全限定名、属性值

properties.load(resourceAsStream);
String className = properties.getProperty("className");
Set<Object> keySet = properties.keySet();

利用反射去加载文件中指定的类，并取得实例

Class<?> loadClass = Class.forName(className);
Object o = loadClass.newInstance();

通过反射获取类中所有的属性，并进行赋值

 Field[] fields = loadClass.getDeclaredFields();
        Arrays.stream(fields).filter(field -> keySet.contains(field.getName())).forEach(field -> {
    
            field.setAccessible(true);
            try {
    
                field.set(o, properties.getProperty(field.getName()));
            } catch (IllegalAccessException e) {
    
                throw new RuntimeException(e);
            }
        });

代码整合

我的Person类

package com.zky.pojo;

/** * @authoer:zky * @createDate:2022/7/30 * @description: */
public class Person {
    

    private String name;
    private String age;
    private String address;

    @Override
    public String toString() {
    
        return "Person{" +
                "name='" + name + '\'' +
                ", age='" + age + '\'' +
                ", address='" + address + '\'' +
                '}';
    }
}

我的School类

package com.zky.pojo;

/** * @authoer:zky * @createDate:2022/7/30 * @description: */
public class School {
    

    private String name;

    private String level;

    @Override
    public String toString() {
    
        return "School{" +
                "name='" + name + '\'' +
                ", level='" + level + '\'' +
                '}';
    }
}

实现类

package com.zky.myframe;

import java.io.InputStream;
import java.lang.reflect.Field;
import java.util.*;
import java.util.function.Consumer;
import java.util.function.Predicate;

/** * @authoer:zky * @createDate:2022/7/30 * @description: */
public class MySpring {
    

    public static final String PROPRETIES_PATH = "application.propreties";


    public static void main(String[] args) throws Exception {
    

        Object o = beanFactory();
        System.out.println(o);

    }

    public static Object beanFactory() throws Exception {
    

        //读取配置文件的信息
        Properties properties = new Properties();
        InputStream resourceAsStream = MySpring.class.getResourceAsStream(PROPRETIES_PATH);
        properties.load(resourceAsStream);
        String className = properties.getProperty("className");
        //TODO 修改为自动获取属性信息
        Set<Object> keySet = properties.keySet();
        //利用反射加载对应的类
        Class<?> loadClass = Class.forName(className);
        Object o = loadClass.newInstance();
        Field[] fields = loadClass.getDeclaredFields();
        Arrays.stream(fields).filter(field -> keySet.contains(field.getName())).forEach(field -> {
    
            field.setAccessible(true);
            try {
    
                field.set(o, properties.getProperty(field.getName()));
            } catch (IllegalAccessException e) {
    
                throw new RuntimeException(e);
            }
        });

        return o;

    }

}

待优化：

目前属性只支持String类型的属性，其它属性等我有空再写~ 感觉不是很好弄。
目前只能管理对象一个对象，多个对象有待实现