ape.TouchCommand.java Source code

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Here is the source code for ape.TouchCommand.java

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/**
  * Copyright (c) 2012 Yahoo! Inc. All rights reserved.
  * Licensed 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. See accompanying LICENSE file.
*/

package ape;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import org.apache.commons.cli.Option;
import org.apache.commons.cli.OptionBuilder;

/**
 * This command touches a file on a given host.  It is used to test if the communication
 * protocol is working properly.  For instance, you can run:
 * 
 * ape -R hostname -t
 * 
 * The above command would touch a file called /tmp/foo.tst.  If this command fails then there is
 * some issue with the PDSHCommunication class.
 * 
 *
 */
public class TouchCommand extends ApeCommand {
    private Option option;

    @Override
    public String getName() {
        return option.getLongOpt();
    }

    /**
     * The constructor for this command simply creates its Option object (used by
     * the CLI parser)
     */
    public TouchCommand() {
        option = OptionBuilder.withValueSeparator().withDescription("Touches a file called /tmp/foo.tst")
                .withLongOpt("touch").create("t");
    }

    public Option getOption() {
        return option;
    }

    public boolean runImpl(String[] args) {
        System.out.println("Going to touch /tmp/foo.tst");

        Runtime rt = Runtime.getRuntime();
        Process p;
        try {
            p = rt.exec("touch /tmp/foo.tst");
            p.waitFor();
            p = rt.exec("ls /tmp");
            p.waitFor();
            return writeSTDOut(p);
        } catch (IOException e) {
            System.out.println("IOException caught in executing command.");
            e.printStackTrace();
            return false;
        } catch (InterruptedException e) {
            System.out.println("The process for the 'ls /tmp' command was interrupted.");
            e.printStackTrace();
            return false;
        }
    }

    private boolean writeSTDOut(Process p) {
        BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));
        String count;
        try {
            while ((count = stdInput.readLine()) != null) {
                System.out.println(count);
            }
            stdInput.close();
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
        return true;
    }
}