/*
 * $Id$
 *
 * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.sun.javatest.agent;

import java.io.ByteArrayInputStream;
import java.io.InputStream;

class AgentClassLoader extends ClassLoader {
    private Agent.Task parent;

    AgentClassLoader(Agent.Task parent) {
        this.parent = parent;
    }

    @Override
    public synchronized Class<?> loadClass(String className, boolean resolve) throws ClassNotFoundException {

        // check the cache first
        Class<?> c = findLoadedClass(className);

        // not found in the cache?
        if (c == null) {
            try {
                ClassLoader cl = getClass().getClassLoader();
                if (cl != null) {
                    // if this class has a class loader, defer to that,
                    // (and assume it will call findSystemClass if necessary)
                    c = cl.loadClass(className);
                } else {
                    // this class must be loaded via system class loader,
                    // so go use that one
                    c = findSystemClass(className);
                }
            } catch (ClassNotFoundException e) {
                AgentRemoteClassData data = parent.getClassData(className);
                c = defineClass(className, data.getByteData(), 0, data.getByteData().length);
            }
        }

        if (resolve) {
            resolveClass(c);
        }

        return c;
    }

    @Override
    public synchronized InputStream getResourceAsStream(String resourceName) {
        // check local classpath first
        // the resource should already be absolute, if we've got here
        // through getClass().getResourceAsStream()
        InputStream in = getClass().getResourceAsStream(resourceName);
        if (in == null) {
            try {
                // if not found here, try remote load from Agent Manager
                byte[] data = parent.getResourceData(resourceName);
                in = new ByteArrayInputStream(data);
            } catch (Exception e) {
                // ignore
            }
        }
        return in;
    }
}
