自定义类加载器，我有困惑 - 黑马程序员技术交流社区

//含有main方法的类
public class ClassLoaderTest {
public static void main(String[] args) throws Exception {
Class clazz = new MyClassLoader().loadClass(" ");
Date d = (Date)clazz.newInstance();
System.out.println(d);
}
}
//我的类加载器
public class MyClassLoader extends ClassLoader{
@Override
public Class findClass(String name){
FileInputStream fi;
String classurl = "D:\\Users\\Administrator\\workspace2\\day2\\day2Class\\Myclass.class";
ByteArrayOutputStream bo = null;
System.out.println("我的类加载器");
try {
fi = new FileInputStream(classurl);
bo = new ByteArrayOutputStream();
int i = -1;
while(true){
i = fi.read();
if(i==-1)break;
bo.write(i);
}
fi.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
byte[] bytes = bo.toByteArray();
return defineClass(bytes,0,bytes.length);
}
}
//我写的测试类
public class Myclass extends Date{
@Override
public String toString(){
return "我是Myclass类中的toString方法。";
}
}

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