123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194 |
- /*
- * 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);
- }
- }
|