Java URLClassLoader动态加载外部java代码

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外部代码

package priv.tuyou;

public class Say {

public void say(){

System.out.println("say priv.tuyou.hello");

}

}

存放路径

动态加载示例

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.URLClassLoader;

import priv.tuyou.Say;

public class URLPathClassLoader extends URLClassLoader{

private String packageName = "priv.tuyou";

public URLPathClassLoader(URL[] classPath, ClassLoader parent){

super(classPath, parent);

}

@Override

protected Class<?> findClass(String name) throws ClassNotFoundException {

Class<?> aClass = findLoadedClass(name);

if(aClass != null){

return aClass;

}

if(!packageName.startsWith(name)){

return super.loadClass(name);

}

return null;

}

public static void main(String[] args) throws MalformedURLException, ClassNotFoundException, SecurityException, NoSuchMethodException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {

URL[] urls = {new URL("file://Users/apple/temp")};

URLPathClassLoader urlPathClassLoader = new URLPathClassLoader(urls, getSystemClassLoader());

Class say = urlPathClassLoader.findClass("priv.tuyou.Say");

Method method = say.getMethod("say");

Object instance = say.newInstance();

method.invoke(instance);

Say say2 = (Say)instance;

say2.say();

}

}

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作者：涂有

来源：CSDN

原文：https://blog.csdn.net/ty497122758/article/details/77170901

版权声明：本文为博主原创文章，转载请附上博文链接！