jgit/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/opt/SubcommandHandler.java

/*
 * 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.opt;

import java.text.MessageFormat;

import org.kohsuke.args4j.CmdLineException;
import org.kohsuke.args4j.CmdLineParser;
import org.kohsuke.args4j.OptionDef;
import org.kohsuke.args4j.spi.OptionHandler;
import org.kohsuke.args4j.spi.Parameters;
import org.kohsuke.args4j.spi.Setter;
import org.eclipse.jgit.pgm.CommandCatalog;
import org.eclipse.jgit.pgm.CommandRef;
import org.eclipse.jgit.pgm.TextBuiltin;

/**
 * Custom Argument handler for jgit command selection.
 * <p>
 * Translates a single argument string to a {@link TextBuiltin} instance which
 * we can execute at runtime with the remaining arguments of the parser.
 */
public class SubcommandHandler extends OptionHandler<TextBuiltin> {
	/**
	 * Create a new handler for the command name.
	 * <p>
	 * This constructor is used only by args4j.
	 *
	 * @param parser
	 * @param option
	 * @param setter
	 */
	public SubcommandHandler(final CmdLineParser parser,
			final OptionDef option, final Setter<? super TextBuiltin> setter) {
		super(parser, option, setter);
	}

	@Override
	public int parseArguments(final Parameters params) throws CmdLineException {
		final String name = params.getParameter(0);
		final CommandRef cr = CommandCatalog.get(name);
		if (cr == null)
			throw new CmdLineException(MessageFormat.format(
					"{0} is not a jgit command", name));

		// Force option parsing to stop. Everything after us should
		// be arguments known only to this command and must not be
		// recognized by the current parser.
		//
		owner.stopOptionParsing();
		setter.addValue(cr.create());
		return 1;
	}

	@Override
	public String getDefaultMetaVariable() {
		return "command";
	}
}