package learn;

import java.io.ByteArrayOutputStream;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.IOException;

import java.nio.ByteBuffer;

import java.nio.channels.Channels;

import java.nio.channels.FileChannel;

import java.nio.channels.WritableByteChannel;

/**

* @author haojian

*

*/

public class MyClassLoader1 extends ClassLoader {

public MyClassLoader1(ClassLoader parent) {

super(parent);

}

public Class<?> findClass1(String name) throws Exception {

byte[] bytes = loadClassBytes(name);

Class theClass = defineClass(null, bytes, 0, bytes.length);

if (theClass == null)

throw new ClassFormatError();

return theClass;

}

private byte[] loadClassBytes(String classFile) throws Exception {

// String classFile = getClassFile();

FileInputStream fis = new FileInputStream(classFile);

FileChannel fileC = fis.getChannel();

ByteArrayOutputStream baos = new ByteArrayOutputStream();

WritableByteChannel outC = Channels.newChannel(baos);

ByteBuffer buffer = ByteBuffer.allocateDirect(1024);

while (true) {

int i = fileC.read(buffer);

if (i == 0 || i == -1) {

break;

}

buffer.flip();

outC.write(buffer);

buffer.clear();

}

fis.close();

return baos.toByteArray();

}

}