ClassPathClassBytesReader.java

package com.avaje.ebean.enhance.agent;

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLClassLoader;

/**
 * Implementation of ClassBytesReader based on URLClassLoader.
 */
public class ClassPathClassBytesReader implements ClassBytesReader {
	

	
	private final URL[] urls;
	
	public ClassPathClassBytesReader(URL[] urls) {
		this.urls = urls == null ? new URL[0]: urls;
	}
	
	public byte[] getClassBytes(String className, ClassLoader classLoader) {

		URLClassLoader cl = new URLClassLoader(urls, classLoader);

		String resource = className.replace('.', '/') + ".class";

		InputStream is = null;
		try {

			// read the class bytes, and define the class
			URL url = cl.getResource(resource);
			if (url == null) {
				throw new RuntimeException("Class Resource not found for "+resource);
			}
	
			is = url.openStream();
			byte[] classBytes = InputStreamTransform.readBytes(is);

			return classBytes;
			
		} catch (IOException e){
			throw new RuntimeException("IOException reading bytes for "+className, e);
			
		} finally {
			if (is != null){
				try {
					is.close();
				} catch (IOException e) {
					throw new RuntimeException("Error closing InputStream for "+className, e);
				}
			}
		}
	}
	
}