/*
 * Licensed to the University of California, Berkeley under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for additional information regarding
 * copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the License. You may obtain a
 * copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package tachyon.shell.command;

import java.io.IOException;

import javax.annotation.concurrent.ThreadSafe;

import org.apache.commons.cli.BasicParser;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;

import tachyon.TachyonURI;
import tachyon.client.file.FileSystem;
import tachyon.conf.TachyonConf;

/**
 * Changes the group of a file or directory specified by args.
 */
@ThreadSafe
public final class ChgrpCommand extends AbstractAclCommand {

  /**
   * Creates a new instance of {@link ChgrpCommand}.
   *
   * @param conf a Tachyon configuration
   * @param fs a Tachyon file system handle
   */
  public ChgrpCommand(TachyonConf conf, FileSystem fs) {
    super(conf, fs);
  }

  @Override
  public String getCommandName() {
    return "chgrp";
  }

  @Override
  protected int getNumOfArgs() {
    return 2;
  }

  @Override
  public void run(String... args) throws IOException {
    CommandLineParser parser = new BasicParser();
    Options options = new Options();
    // Add R option or chgrp recursively.
    options.addOption("R", false, "recursively");
    CommandLine cmd;
    try {
      cmd = parser.parse(options, args);
    } catch (ParseException e) {
      System.err.println("Unable to parse input args: " + e.getMessage());
      return;
    }

    String group = cmd.getArgs()[0];
    TachyonURI path = new TachyonURI(cmd.getArgs()[1]);

    chgrp(path, group, cmd.hasOption("R"));
  }

  @Override
  public String getUsage() {
    return "chgrp [-R] <group> <path>";
  }

  @Override
  public String getDescription() {
    return "Changes the group of a file or directory specified by args.\n"
        + "Specify -R to change the group recursively.";
  }

  @Override
  public boolean validateArgs(String... args) {
    boolean valid = args.length >= getNumOfArgs();
    if (!valid) {
      System.out.println(getCommandName() + " takes " + getNumOfArgs() + " argument at least\n");
    }
    return valid;
  }
}

@@ -1909,16 +1909,17 @@
  option 
+f
 or chgrp

Fix typo in comment.