mbeanhelper.java

mobile to system control

/*
 *   This file is part of MobiMon.
 *
 *   MobiMon is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   MobiMon is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.

 *   You should have received a copy of the GNU General Public License
 *   along with MobiMon; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
/*
 * MBeanHelper.java
 *
 * Created on March 5, 2003, 8:26 AM
 */

package mobimon.mbeans;

import java.io.*;
import java.nio.*;
import java.nio.channels.*;
import mobimon.common.*;


/**
 *
 * @author  jan
 */

public class MBeanHelper {
    
    /** Creates a new instance of MBeanHelper */
    public MBeanHelper() {
    }
    
    public static byte[] executeCommand(String command) {
        byte[] barr = null;
        Runtime rt = Runtime.getRuntime();
        try {
            Process pr = rt.exec(command);
            StreamEater eatStdout = new StreamEater(pr.getInputStream());
            StreamEater eatStderr = new StreamEater(pr.getErrorStream());
            Thread out = new Thread(eatStdout);
            Thread err = new Thread(eatStderr);
            out.start();
            err.start();
            int retVal = pr.waitFor();
            barr = (retVal == 0) ? eatStdout.getBytes() : eatStderr.getBytes();
        } catch (Exception e) {
            System.out.println(e.getClass().getName() + ":" + e.getMessage());
            barr = null;
        }
        return barr;
    }
    
    public static Page getFileContents(String fileName, int where) {
        byte[] fileContents = null;
        int pos = Math.abs(where);
        Page page = null;
        try {
            FileInputStream fis = new FileInputStream(fileName);
            FileChannel fc = fis.getChannel();
            long fileSize = fc.size();
            MappedByteBuffer mbb =
            fc.map(FileChannel.MapMode.READ_ONLY, 0, fileSize);
            if (where > 0) {
                if ((pos * Page.SIZE) >= fileSize) {
                    pos = (int)(fileSize / Page.SIZE);
                    mbb.position(pos * Page.SIZE);
                    pos = 0;
                } else {
                    mbb.position(--pos * Page.SIZE);
                    pos = where + 1;
                }
            } else if (where < 0) {
                if ((pos * Page.SIZE) >= fileSize) {
                    mbb.position(0);
                    pos = 0;
                } else {
                    mbb.position((int)(fileSize - (pos * Page.SIZE)));
                    pos = where - 1;
                }
            } else {
                pos = 0;
                mbb.position(0);
            }
            if (mbb.hasRemaining()) {
                fileContents = new byte[Math.min(mbb.remaining(), Page.SIZE)];
                mbb.get(fileContents);
            }
            fc.close();
            fis.close();
            page = new Page(pos, fileContents);
        } catch (IOException ioe) {
            page = new Page(0, null);
        }
        return page;
    }
}