tachyon.shell.command.ChmodCommand.java Source code

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Here is the source code for tachyon.shell.command.ChmodCommand.java

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/*
 * 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.CommandLine;
import org.apache.commons.cli.Options;

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

/**
 * Changes the permission of a file or directory specified by args.
 */
@ThreadSafe
public final class ChmodCommand extends AbstractTfsShellCommand {

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

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

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

    @Override
    protected Options getOptions() {
        return new Options().addOption(RECURSIVE_OPTION);
    }

    /**
     * Changes the permissions of directory or file with the path specified in args.
     *
     * @param path The {@link TachyonURI} path as the input of the command
     * @param modeStr The new permission to be updated to the file or directory
     * @param recursive Whether change the permission recursively
     * @throws IOException if command failed
     */
    private void chmod(TachyonURI path, String modeStr, boolean recursive) throws IOException {
        short newPermission = 0;
        try {
            newPermission = Short.parseShort(modeStr, 8);
            SetAttributeOptions options = SetAttributeOptions.defaults().setPermission(newPermission)
                    .setRecursive(recursive);
            mFileSystem.setAttribute(path, options);
            System.out.println("Changed permission of " + path + " to " + Integer.toOctalString(newPermission));
        } catch (Exception e) {
            throw new IOException("Failed to changed permission of  " + path + " to "
                    + Integer.toOctalString(newPermission) + " : " + e.getMessage());
        }
    }

    @Override
    public void run(CommandLine cl) throws IOException {
        String[] args = cl.getArgs();
        String modeStr = args[0];
        TachyonURI path = new TachyonURI(args[1]);
        chmod(path, modeStr, cl.hasOption("R"));
    }

    @Override
    public String getUsage() {
        return "chmod -R <mode> <path>";
    }

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