import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;

public class DemonstrationLoader extends ClassLoader {

	public Class findClass(String name) throws ClassNotFoundException {
		byte[] b= loadClassData(name);
		Class result= defineClass(name, b, 0, b.length);
		if (result == null) {
			throw new ClassNotFoundException(name);
		}
		return result;
	}

	private byte[] loadClassData(String name) {
		File f= getPath(name);
		long fileSize= (int) f.length();
		if (fileSize > Integer.MAX_VALUE)
			throw new RuntimeException("too much bytecode");
		int bytecodeSize= (int) fileSize;
		byte[] array= new byte[(int) bytecodeSize];
		BufferedInputStream bis= null;
		try {
			FileInputStream fis= new FileInputStream(f);
			bis= new BufferedInputStream(fis);
			bis.read(array, 0, bytecodeSize);
		} catch (IOException e) {
		} finally {
			try {
				if (bis != null)
					bis.close();
			} catch (IOException e) {
			}
		}
		return array;
	}

	static final String SEP= System.getProperty("file.separator");

	public File getPath(String name) {
		return new File("." + SEP + "classes" + SEP + name + ".class");
	}

}