import java.io.*;
import java.util.Hashtable;

public class DirectClassLoader extends ClassLoader
{
    protected final ClassLoader parent;
    private final Hashtable definedClasses = new Hashtable();
    public DirectClassLoader()
    {
        this(DirectClassLoader.class.getClassLoader());
    }
    public DirectClassLoader(ClassLoader _parent)
    {
        parent = _parent;
    }
    protected synchronized Class loadClass(String name, boolean resolve) throws ClassNotFoundException
    {
        Class cls = findLoadedClass(name);
        if (cls == null && parent != null)
        {
            try
            {
                cls = parent.loadClass(name);
            }
            catch (ClassNotFoundException e)
            {

            }
        }
        if (cls == null)
            cls = findClass(name);
        if (resolve)
            resolveClass(cls);
        return cls;
    }
    public Class loadClass(File file)throws ClassNotFoundException,IOException
    {
        return loadClass(new FileInputStream(file));
    }
    public Class loadClass(InputStream in)throws ClassNotFoundException,IOException
    {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        byte[] buf = new byte[1024];
        for( ; ; )
        {
            int l = in.read(buf);
            if (l <= 0)
                break;
            out.write(buf,0,l);
        }
        in.close();
        return loadClass(out.toByteArray());
    }
    public Class loadClass(byte[] b)throws ClassNotFoundException
    {
        return loadClass(b,0,b.length);
    }
    public Class loadClass(byte[] b,int off,int len) throws ClassNotFoundException
    {
        Class cls = defineClass(null,b,off,len);
        definedClasses.put(cls.getName(),cls);
        return loadClass(cls.getName());
    }
    protected Class findClass(String name) throws ClassNotFoundException
    {
        Class cls = (Class)definedClasses.get(name);
        if (cls == null)
            throw new ClassNotFoundException(name);
        else
            return cls;
    }
}