content: /*
   * Universal Password Manager
   * Copyright (c) 2010-2011 Adrian Smith
   *
   * This file is part of Universal Password Manager.
   *   
   * Universal Password Manager 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.
   *
   * Universal Password Manager 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 Universal Password Manager; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   */
  package com.u17od.upm.util;
  
  import java.io.ByteArrayOutputStream;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStreamWriter;
  import java.nio.charset.Charset;
  
  
  public class Util {
  
      /**
       * Left pad an integer to a given length with the given
       * character 
       * @param i The integer to pad
       * @param length The length to pad it to
       * @param c The character to do the padding with
       * @return A padded version of the integer
       */
      public static String lpad(int i, int length, char c) {
          StringBuffer buf = new StringBuffer(String.valueOf(i));
          while (buf.length() < length) {
              buf.insert(0, c);
          }
          return buf.toString();
      }
  
  
      public static byte[] getBytesFromFile(File file) throws IOException {
          return getBytesFromFile(file, file.length());
      }
  
      public static byte[] getBytesFromFile(File file, long numBytesToRead) throws IOException {
          InputStream is = new FileInputStream(file);
      
          // Create the byte array to hold the data
          byte[] bytes = new byte[(int) numBytesToRead];
      
          // Read in the bytes
          int offset = 0;
          int numRead = 0;
          while (offset < bytes.length
                 && (numRead=is.read(bytes, offset, bytes.length-offset)) >= 0) {
              offset += numRead;
          }
      
          // Ensure all the bytes have been read in
          if (offset < bytes.length) {
              is.close();
              throw new IOException("Could not completely read file " + file.getName());
          }
  
          is.close();
  
          return bytes;
      }
  
      public static Charset defaultCharset() {
          return Charset.forName(
                  new OutputStreamWriter(
                          new ByteArrayOutputStream()).getEncoding());
      }
  
  }
  