/*
* This file is part of the OdinMS Maple Story Server Copyright (C) 2008 ~ 2010
* Patrick Huy <patrick.huy@frz.cc> Matthias Butz <matze@odinms.de> Jan
* Christian Meyer <vimes@odinms.de>
*
* This program is free software: you can redistribute it and/or modify it under
* the terms of the GNU Affero General Public License version 3 as published by
* the Free Software Foundation. You may not use, modify or distribute this
* program under any other version of the GNU Affero General Public License.
*
* This program 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 Affero General Public License for more
* details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package javastory.tools;
/**
* Provides static methods for working with raw byte sequences.
*
* @author Frz
* @since Revision 206
* @version 1.0
*/
public class BitTools {
/**
* Reads a short from <code>array</code> at <code>index</code>
*
* @param array
* The byte array to read the short integer from.
* @param index
* Where reading begins.
* @return The short integer value.
*/
public static int getShort(final byte array[], final int index) {
int ret = array[index];
ret &= 0xFF;
ret |= array[index + 1] << 8 & 0xFF00;
return ret;
}
/**
* Reads a string from <code>array</code> at <code>index</code>
* <code>length</code> in length.
*
* @param array
* The array to read the string from.
* @param index
* Where reading begins.
* @param length
* The number of bytes to read.
* @return The string read.
*/
public static String getString(final byte array[], final int index, final int length) {
final char[] cret = new char[length];
for (int x = 0; x < length; x++) {
cret[x] = (char) array[x + index];
}
return String.valueOf(cret);
}
/**
* Reads a maplestory-convention string from <code>array</code> at
* <code>index</code>
*
* @param array
* The byte array to read from.
* @param index
* Where reading begins.
* @return The string read.
*/
public static String getMapleString(final byte array[], final int index) {
final int length = array[index] & 0xFF | array[index + 1] << 8 & 0xFF00;
return BitTools.getString(array, index + 2, length);
}
/**
* Turns a double-precision floating point integer into an integer.
*
* @param d
* The double to transform.
* @return The converted integer.
*/
public static int doubleshofteertBits(final double d) {
final long l = Double.doubleToLongBits(d);
return (int) (l >> 48);
}
}