/* * ModuleLoader - A generic, policy-driven class loader. * Copyright (c) 2004, Richard S. Hall * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * *   * Redistributions of source code must retain the above copyright *     notice, this list of conditions and the following disclaimer. *   * Redistributions in binary form must reproduce the above copyright *     notice, this list of conditions and the following disclaimer in *     the documentation and/or other materials provided with the *     distribution. *   * Neither the name of the ungoverned.org nor the names of its *     contributors may be used to endorse or promote products derived *     from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * Contact: Richard S. Hall (heavy@ungoverned.org) * Contributor(s): ***/package org.ungoverned.moduleloader;/** * <p> * This interface represents a source for obtaining resources for a * given module via the module's class loader. A resource source is used * for retrieving both classes and resources; at this level, classes are * treated in an identical manner as an ordinary resource. Resource sources * are completely arbitrary and implementations may load resources from a JAR * file, the network, a database, or anywhere. * </p> * <p> * All resource sources are initialized before first usage via a call * to the <a href="#open()"><tt>ResourceSource.open()</tt></a> method and * are also deinitialized via a call to * <a href="#open()"><tt>ResourceSource.close()</tt></a>. Resource sources * should be implemented such that they can be opened, closed, and then * re-opened. * </p> * @see org.ungoverned.moduleloader.Module * @see org.ungoverned.moduleloader.ModuleClassLoader**/public interface ResourceSource{    /**     * <p>     * This method initializes the resource source. It is called when     * the associated module is added to the <tt>ModuleManager</tt>. It     * is acceptable for implementations to ignore duplicate calls to this     * method if the resource source is already opened.     * </p>    **/    public void open();    /**     * <p>     * This method de-initializes the resource source. It is called when     * the associated module is removed from the <tt>ModuleManager</tt> or     * when the module is reset by the <tt>ModuleManager</tt>.     * </p>    **/    public void close();    /**     * <p>     * This method returns a boolean indicating whether the resource source     * contains the specified resource.     * </p>     * @param name the name of the resource whose existence is being checked.     * @param <tt>true</tt> if the resource source has the resource, <tt>false</tt>     *        otherwise.     * @throws java.lang.IllegalStateException if the resource source has not     *         been opened.    **/    public boolean hasResource(String name) throws IllegalStateException;    /**     * <p>     * This method returns a byte array of the specified resource's contents.     * </p>     * @param name the name of the resource to retrieve.     * @param a byte array of the resource's contents or <tt>null</tt>     *        if the resource was not found.     * @throws java.lang.IllegalStateException if the resource source has not     *         been opened.    **/    public byte[] getBytes(String name) throws IllegalStateException;}