/* * 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.search.selection;import java.io.BufferedReader;import java.io.InputStreamReader;import org.ungoverned.moduleloader.Module;import org.ungoverned.moduleloader.search.SelectionPolicy;import org.ungoverned.moduleloader.search.CompatibilityPolicy;/** * This class implements an interactive selection policy for the * <tt>ImportSearchPolicy</tt>. This policy simply uses standard * output to present the list of candidate modules and uses standard * input to allow the user to select a specific module from the * candidates. This selection policy is generally only useful for * debugging purposes. * @see org.ungoverned.moduleloader.search.SelectionPolicy * @see org.ungoverned.moduleloader.search.ImportSearchPolicy**/public class InteractiveSelectionPolicy implements SelectionPolicy{    /**     * Returns a single package from an array of packages.     * @param sources array of packages from which to choose.     * @return the selected package or <tt>null</tt> if no package     *         can be selected.    **/    public Module select(Module module, Object target,        Object version, Module[] candidates, CompatibilityPolicy compatPolicy)    {        try {            if (candidates.length == 1)            {                return candidates[0];            }            // Now start an interactive prompt.            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));            do            {                System.out.println("\nImporting '" + target                    + "(" + version + ")" + "' for '" + module + "'.");                System.out.println("");                for (int i = 0; i < candidates.length; i++)                {                    System.out.println((i + 1) + ". " + candidates[i]);                }                System.out.print("Select: ");                String s = br.readLine();                int choice = -1;                try {                    choice = Integer.parseInt(s);                } catch (Exception ex) {                }                if (choice == 0)                {                    break;                }                else if ((choice > 0) && (choice <= candidates.length))                {                    return candidates[choice - 1];                }            }            while (true);        } catch (Exception ex) {        }        return null;    }}