| /* |
| * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> |
| * and other copyright owners as documented in the project's IP log. |
| * |
| * This program and the accompanying materials are made available |
| * under the terms of the Eclipse Distribution License v1.0 which |
| * accompanies this distribution, is reproduced below, and is |
| * available at http://www.eclipse.org/org/documents/edl-v10.php |
| * |
| * 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 Eclipse Foundation, Inc. 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. |
| */ |
| |
| package org.eclipse.jgit.pgm; |
| |
| import java.io.BufferedReader; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.InputStreamReader; |
| import java.net.URL; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Collection; |
| import java.util.Comparator; |
| import java.util.Enumeration; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Vector; |
| |
| /** |
| * List of all commands known by jgit's command line tools. |
| * <p> |
| * Commands are implementations of {@link TextBuiltin}, with an optional |
| * {@link Command} class annotation to insert additional documentation or |
| * override the default command name (which is guessed from the class name). |
| * <p> |
| * Commands may be registered by adding them to a services file in the same JAR |
| * (or classes directory) as the command implementation. The service file name |
| * is <code>META-INF/services/org.eclipse.jgit.pgm.TextBuiltin</code> and it |
| * contains one concrete implementation class name per line. |
| * <p> |
| * Command registration is identical to Java 6's services, however the catalog |
| * uses a lightweight wrapper to delay creating a command instance as much as |
| * possible. This avoids initializing the AWT or SWT GUI toolkits even if the |
| * command's constructor might require them. |
| */ |
| public class CommandCatalog { |
| private static final CommandCatalog INSTANCE = new CommandCatalog(); |
| |
| /** |
| * Locate a single command by its user friendly name. |
| * |
| * @param name |
| * name of the command. Typically in dash-lower-case-form, which |
| * was derived from the DashLowerCaseForm class name. |
| * @return the command instance; null if no command exists by that name. |
| */ |
| public static CommandRef get(final String name) { |
| return INSTANCE.commands.get(name); |
| } |
| |
| /** |
| * @return all known commands, sorted by command name. |
| */ |
| public static CommandRef[] all() { |
| return toSortedArray(INSTANCE.commands.values()); |
| } |
| |
| /** |
| * @return all common commands, sorted by command name. |
| */ |
| public static CommandRef[] common() { |
| final ArrayList<CommandRef> common = new ArrayList<CommandRef>(); |
| for (final CommandRef c : INSTANCE.commands.values()) |
| if (c.isCommon()) |
| common.add(c); |
| return toSortedArray(common); |
| } |
| |
| private static CommandRef[] toSortedArray(final Collection<CommandRef> c) { |
| final CommandRef[] r = c.toArray(new CommandRef[c.size()]); |
| Arrays.sort(r, new Comparator<CommandRef>() { |
| public int compare(final CommandRef o1, final CommandRef o2) { |
| return o1.getName().compareTo(o2.getName()); |
| } |
| }); |
| return r; |
| } |
| |
| private final ClassLoader ldr; |
| |
| private final Map<String, CommandRef> commands; |
| |
| private CommandCatalog() { |
| ldr = Thread.currentThread().getContextClassLoader(); |
| commands = new HashMap<String, CommandRef>(); |
| |
| final Enumeration<URL> catalogs = catalogs(); |
| while (catalogs.hasMoreElements()) |
| scan(catalogs.nextElement()); |
| } |
| |
| private Enumeration<URL> catalogs() { |
| try { |
| final String pfx = "META-INF/services/"; //$NON-NLS-1$ |
| return ldr.getResources(pfx + TextBuiltin.class.getName()); |
| } catch (IOException err) { |
| return new Vector<URL>().elements(); |
| } |
| } |
| |
| private void scan(final URL cUrl) { |
| final BufferedReader cIn; |
| try { |
| final InputStream in = cUrl.openStream(); |
| cIn = new BufferedReader(new InputStreamReader(in, "UTF-8")); //$NON-NLS-1$ |
| } catch (IOException err) { |
| // If we cannot read from the service list, go to the next. |
| // |
| return; |
| } |
| |
| try { |
| String line; |
| while ((line = cIn.readLine()) != null) { |
| if (line.length() > 0 && !line.startsWith("#")) //$NON-NLS-1$ |
| load(line); |
| } |
| } catch (IOException err) { |
| // If we failed during a read, ignore the error. |
| // |
| } finally { |
| try { |
| cIn.close(); |
| } catch (IOException e) { |
| // Ignore the close error; we are only reading. |
| } |
| } |
| } |
| |
| private void load(final String cn) { |
| final Class<? extends TextBuiltin> clazz; |
| try { |
| clazz = Class.forName(cn, false, ldr).asSubclass(TextBuiltin.class); |
| } catch (ClassNotFoundException notBuiltin) { |
| // Doesn't exist, even though the service entry is present. |
| // |
| return; |
| } catch (ClassCastException notBuiltin) { |
| // Isn't really a builtin, even though its listed as such. |
| // |
| return; |
| } |
| |
| final CommandRef cr; |
| final Command a = clazz.getAnnotation(Command.class); |
| if (a != null) |
| cr = new CommandRef(clazz, a); |
| else |
| cr = new CommandRef(clazz); |
| |
| commands.put(cr.getName(), cr); |
| } |
| } |