JVM ClassLoaderTest

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package com.test.demo;

import java.io.IOException;
import java.io.InputStream;

public class ClassLoaderTest {
    public static void main(String[] args) throws Exception{
        ClassLoader myLoader = new ClassLoader() {
            @Override
            public Class<?> loadClass(String name) throws ClassNotFoundException {
                try {
                    String fileName = name.substring(name.lastIndexOf(".")+1)+".class";
                    InputStream is = getClass().getResourceAsStream(fileName);
                    if (is == null) {
                        return super.loadClass(name);
                    }
                    byte[] b = new byte[is.available()];
                    is.read(b);
                    return defineClass(name, b, 0, b.length);
                }catch (IOException e) {
                    throw new ClassNotFoundException(name);
                }
            }
        };

        Object obj = myLoader.loadClass("com.test.demo.ClassLoaderTest").newInstance();
        System.out.println(obj.getClass());
        System.out.println(obj instanceof ClassLoaderTest);
    }
}

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