root / tags / v1_0_RELEASE / libraries / libDwg / src / com / iver / cit / javacad / util / ByteUtils.java @ 9167
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/* gvSIG. Sistema de Informaci?n Geogr?fica de la Generalitat Valenciana
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*
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* Copyright (C) 2004 IVER T.I. and Generalitat Valenciana.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,USA.
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*
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* For more information, contact:
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*
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* Generalitat Valenciana
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* Conselleria d'Infraestructures i Transport
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* Av. Blasco Ib??ez, 50
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* 46010 VALENCIA
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* SPAIN
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*
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* +34 963862235
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* gvsig@gva.es
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* www.gvsig.gva.es
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*
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* or
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*
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* IVER T.I. S.A
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* Salamanca 50
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* 46005 Valencia
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* Spain
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*
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* +34 963163400
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* dac@iver.es
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*/
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package com.iver.cit.javacad.util; |
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import java.math.BigInteger; |
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/**
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* Clase que engloba m?todos para trabajar con bytes.
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*
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* @author Vicente Caballero Navarro
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*/
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public class ByteUtils { |
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public static final int SIZE_BOOL = 1; |
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public static final int SIZE_SHORT = 2; |
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public static final int SIZE_INT = 4; |
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public static final int SIZE_LONG = 8; |
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public static final int SIZE_DOUBLE = 8; |
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|
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/** A nibble->char mapping for printing out bytes. */
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public static final char[] digits = { |
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'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', |
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'e', 'f' |
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}; |
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/**
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* Return the <code>int</code> represented by the bytes in
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* <code>data</code> staring at offset <code>offset[0]</code>.
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*
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* @param data the array from which to read
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* @param offset A single element array whose first element is the index in
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* data from which to begin reading on function entry, and which on
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* function exit has been incremented by the number of bytes read.
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*
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* @return the value of the <code>int</code> decoded
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*/
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public static final int bytesToInt(byte[] data, int[] offset) { |
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/**
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* TODO: We use network-order within OceanStore, but temporarily
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* supporting intel-order to work with some JNI code until JNI code is
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* set to interoperate with network-order.
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*/
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int result = 0; |
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for (int i = 0; i < SIZE_INT; ++i) { |
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result <<= 8;
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result |= byteToUnsignedInt(data[offset[0]++]);
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} |
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return result;
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} |
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/**
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* Write the bytes representing <code>i</code> into the byte array
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* <code>data</code>, starting at index <code>offset [0]</code>, and
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* increment <code>offset [0]</code> by the number of bytes written; if
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* <code>data == null</code>, increment <code>offset [0]</code> by the
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* number of bytes that would have been written otherwise.
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*
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* @param i the <code>int</code> to encode
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* @param data The byte array to store into, or <code>null</code>.
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* @param offset A single element array whose first element is the index in
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* data to begin writing at on function entry, and which on
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* function exit has been incremented by the number of bytes
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* written.
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*/
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public static final void intToBytes(int i, byte[] data, int[] offset) { |
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/**
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* TODO: We use network-order within OceanStore, but temporarily
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* supporting intel-order to work with some JNI code until JNI code is
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* set to interoperate with network-order.
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*/
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if (data != null) { |
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for (int j = (offset[0] + SIZE_INT) - 1; j >= offset[0]; --j) { |
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data[j] = (byte) i;
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i >>= 8;
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} |
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} |
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offset[0] += SIZE_INT;
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} |
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/**
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* Return the <code>short</code> represented by the bytes in
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* <code>data</code> staring at offset <code>offset[0]</code>.
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*
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* @param data the array from which to read
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* @param offset A single element array whose first element is the index in
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* data from which to begin reading on function entry, and which on
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* function exit has been incremented by the number of bytes read.
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*
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* @return the value of the <code>short</code> decoded
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*/
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public static final short bytesToShort(byte[] data, int[] offset) { |
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/**
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* TODO: We use network-order within OceanStore, but temporarily
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* supporting intel-order to work with some JNI code until JNI code is
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* set to interoperate with network-order.
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*/
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short result = 0; |
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for (int i = 0; i < SIZE_SHORT; ++i) { |
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result <<= 8;
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result |= (short) byteToUnsignedInt(data[offset[0]++]); |
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} |
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return result;
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} |
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/**
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* Write the bytes representing <code>s</code> into the byte array
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* <code>data</code>, starting at index <code>offset [0]</code>, and
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* increment <code>offset [0]</code> by the number of bytes written; if
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* <code>data == null</code>, increment <code>offset [0]</code> by the
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* number of bytes that would have been written otherwise.
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*
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* @param s the <code>short</code> to encode
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* @param data The byte array to store into, or <code>null</code>.
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* @param offset A single element array whose first element is the index in
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* data to begin writing at on function entry, and which on
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* function exit has been incremented by the number of bytes
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* written.
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*/
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public static final void shortToBytes(short s, byte[] data, int[] offset) { |
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/**
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* TODO: We use network-order within OceanStore, but temporarily
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* supporting intel-order to work with some JNI code until JNI code is
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* set to interoperate with network-order.
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*/
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if (data != null) { |
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data[offset[0] + 1] = (byte) s; |
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data[offset[0]] = (byte) (s >> 8); |
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} |
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offset[0] += SIZE_SHORT;
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} |
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/**
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* Return the <code>long</code> represented by the bytes in
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* <code>data</code> staring at offset <code>offset[0]</code>.
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*
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* @param data the array from which to read
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* @param offset A single element array whose first element is the index in
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* data from which to begin reading on function entry, and which
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* on function exit has been incremented by the number of bytes
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* read.
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*
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* @return the value of the <code>long</code> decoded
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*/
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public static final long bytesToLong(byte[] data, int[] offset) { |
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long result = 0; |
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for (int i = 0; i < SIZE_LONG; ++i) { |
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result <<= 8;
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int res = byteToUnsignedInt(data[offset[0]++]); |
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result = result | res; |
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} |
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return result;
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} |
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/**
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* Write the bytes representing <code>l</code> into the byte array
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* <code>data</code>, starting at index <code>offset [0]</code>, and
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* increment <code>offset [0]</code> by the number of bytes written; if
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* <code>data == null</code>, increment <code>offset [0]</code> by the
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* number of bytes that would have been written otherwise.
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*
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* @param l the <code>long</code> to encode
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* @param data The byte array to store into, or <code>null</code>.
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* @param offset A single element array whose first element is the index in
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* data to begin writing at on function entry, and which on
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* function exit has been incremented by the number of bytes
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* written.
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*/
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public static final void longToBytes(long l, byte[] data, int[] offset) { |
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/**
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* TODO: We use network-order within OceanStore, but temporarily
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* supporting intel-order to work with some JNI code until JNI code is
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* set to interoperate with network-order.
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*/
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if (data != null) { |
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for (int j = (offset[0] + SIZE_LONG) - 1; j >= offset[0]; --j) { |
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data[j] = (byte) l;
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l >>= 8;
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} |
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} |
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offset[0] += SIZE_LONG;
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} |
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/**
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* Return the <code>double</code> represented by the bytes in
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* <code>data</code> staring at offset <code>offset[0]</code>.
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*
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* @param data the array from which to read
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* @param offset A single element array whose first element is the index in
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* data from which to begin reading on function entry, and which
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* on function exit has been incremented by the number of bytes
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* read.
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*
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* @return the value of the <code>double</code> decoded
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*/
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public static final double bytesToDouble(byte[] data, int[] offset) { |
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long bits = bytesToLong(data, offset);
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return Double.longBitsToDouble(bits); |
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} |
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/**
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* Write the bytes representing <code>d</code> into the byte array
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* <code>data</code>, starting at index <code>offset [0]</code>, and
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* increment <code>offset [0]</code> by the number of bytes written; if
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* <code>data == null</code>, increment <code>offset [0]</code> by the
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* number of bytes that would have been written otherwise.
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*
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* @param d the <code>double</code> to encode
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* @param data The byte array to store into, or <code>null</code>.
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* @param offset A single element array whose first element is the index in
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* data to begin writing at on function entry, and which on
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* function exit has been incremented by the number of bytes
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* written.
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*/
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public static final void doubleToBytes(double d, byte[] data, int[] offset) { |
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long bits = Double.doubleToLongBits(d); |
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longToBytes(bits, data, offset); |
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} |
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|
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/**
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* Return the <code>String</code> represented by the bytes in
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* <code>data</code> staring at offset <code>offset[0]</code>. This method
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* relies on the user using the corresponding <code>stringToBytes</code>
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* method to encode the <code>String</code>, so that it may properly
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* retrieve the <code>String</code> length.
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*
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* @param data the array from which to read
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* @param offset A single element array whose first element is the index in
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* data from which to begin reading on function entry, and which on
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* function exit has been incremented by the number of bytes read.
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*
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* @return the value of the <code>String</code> decoded
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*/
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public static final String bytesToString(byte[] data, int[] offset) { |
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offset[0] = 0; |
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int length = bytesToInt(data, offset);
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String st = null; |
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if ((length < 0) || (length > data.length)) { |
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st = new String(data); |
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} else {
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st = new String(data, offset[0], length); |
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} |
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offset[0] += length;
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return st;
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} |
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/**
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* Write the bytes representing <code>s</code> into the byte array
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* <code>data</code>, starting at index <code>offset [0]</code>, and
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* increment <code>offset [0]</code> by the number of bytes written; if
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* <code>data == null</code>, increment <code>offset [0]</code> by the
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* number of bytes that would have been written otherwise.
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*
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* @param s the <code>String</code> to encode
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* @param data The byte array to store into, or <code>null</code>.
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* @param offset A single element array whose first element is the index in
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* data to begin writing at on function entry, and which on
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* function exit has been incremented by the number of bytes
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* written.
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*/
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public static final void stringToBytes(String s, byte[] data, int[] offset) { |
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byte[] s_bytes = s.getBytes(); |
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if (data != null) { |
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intToBytes(s_bytes.length, data, offset); |
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memcpy(data, offset[0], s_bytes, 0, s_bytes.length); |
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} else {
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offset[0] += SIZE_INT;
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} |
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offset[0] += s_bytes.length;
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} |
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/**
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* Return the <code>boolean</code> represented by the bytes in
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* <code>data</code> staring at offset <code>offset[0]</code>.
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*
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* @param data the array from which to read
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* @param offset A single element array whose first element is the index in
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* data from which to begin reading on function entry, and which
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* on function exit has been incremented by the number of bytes
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* read.
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*
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* @return the value of the <code>boolean</code> decoded
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*/
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public static final boolean bytesToBool(byte[] data, int[] offset) { |
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boolean result = true; |
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if (data[offset[0]] == 0) { |
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result = false;
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} |
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offset[0] += SIZE_BOOL;
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return result;
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} |
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|
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/**
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* Write the bytes representing <code>b</code> into the byte array
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* <code>data</code>, starting at index <code>offset [0]</code>, and
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* increment <code>offset [0]</code> by the number of bytes written; if
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* <code>data == null</code>, increment <code>offset [0]</code> by the
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* number of bytes that would have been written otherwise.
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*
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* @param b the <code>boolean</code> to encode
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* @param data The byte array to store into, or <code>null</code>.
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* @param offset A single element array whose first element is the index in
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* data to begin writing at on function entry, and which on
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* function exit has been incremented by the number of bytes
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* written.
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*/
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public static final void boolToBytes(boolean b, byte[] data, int[] offset) { |
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if (data != null) { |
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data[offset[0]] = (byte) (b ? 1 : 0); |
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} |
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offset[0] += SIZE_BOOL;
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} |
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|
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/**
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* Return the <code>BigInteger</code> represented by the bytes in
|
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* <code>data</code> staring at offset <code>offset[0]</code>.
|
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*
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* @param data the array from which to read
|
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* @param offset A single element array whose first element is the index in
|
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* data from which to begin reading on function entry, and which
|
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* on function exit has been incremented by the number of bytes
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* read.
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*
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* @return the <code>BigInteger</code> decoded
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*/
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public static final BigInteger bytesToBigInteger(byte[] data, int[] offset) { |
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int length = bytesToInt(data, offset);
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byte[] bytes = new byte[length]; |
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offset[0] += memcpy(bytes, 0, data, offset[0], length); |
387 |
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return new BigInteger(bytes); |
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} |
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|
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/**
|
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* Write the bytes representing <code>n</code> into the byte array
|
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* <code>data</code>, starting at index <code>offset [0]</code>, and
|
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* increment <code>offset [0]</code> by the number of bytes written; if
|
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* <code>data == null</code>, increment <code>offset [0]</code> by the
|
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* number of bytes that would have been written otherwise.
|
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*
|
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* @param n the <code>BigInteger</code> to encode
|
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* @param data The byte array to store into, or <code>null</code>.
|
400 |
* @param offset A single element array whose first element is the index in
|
401 |
* data to begin writing at on function entry, and which on
|
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* function exit has been incremented by the number of bytes
|
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* written.
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*/
|
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public static final void bigIntegerToBytes(BigInteger n, byte[] data, |
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int[] offset) { |
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byte[] bytes = n.toByteArray(); |
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intToBytes(bytes.length, data, offset); |
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offset[0] += memcpy(data, offset[0], bytes, 0, bytes.length); |
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} |
411 |
|
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/**
|
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* Convert an array of <code>bytes</code>s into an array of
|
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* <code>ints</code>.
|
415 |
*
|
416 |
* @param dst the array to write
|
417 |
* @param dst_offset the start offset in <code>dst</code>, times 4. This
|
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* measures the offset as if <code>dst</code> were an array of
|
419 |
* <code>byte</code>s (rather than <code>int</code>s).
|
420 |
* @param src the array to read
|
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* @param src_offset the start offset in <code>src</code>
|
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* @param length the number of <code>byte</code>s to copy.
|
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*/
|
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public static final void bytesToInts(int[] dst, int dst_offset, byte[] src, |
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int src_offset, int length) { |
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if ((src == null) || (dst == null) || |
427 |
((src_offset + length) > src.length) || |
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((dst_offset + length) > (dst.length * 4)) ||
|
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((dst_offset % 4) != 0) || ((length % 4) != 0)) { |
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croak("bytesToInts parameters are invalid" + " src==" + src + |
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" dst==" + dst +
|
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(((src == null) || (dst == null)) ? " " |
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: (" (src_offset+length)>src.length==" +
|
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(src_offset + length) + ">" + src.length +
|
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" (dst_offset+length)>(dst.length*4)==" +
|
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(dst_offset + length) + ">" + (dst.length * 4) + |
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" (dst_offset%4)==" + (dst_offset % 4) + " (length%4)==" + |
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(length % 4) + " dest.length==" + dst.length + " length==" + |
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length))); |
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} |
441 |
|
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// Convert parameters to normal format
|
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int[] offset = new int[1]; |
444 |
offset[0] = src_offset;
|
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|
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int int_dst_offset = dst_offset / 4; |
447 |
|
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for (int i = 0; i < (length / 4); ++i) { |
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dst[int_dst_offset++] = bytesToInt(src, offset); |
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} |
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} |
452 |
|
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/**
|
454 |
* Convert an array of <code>int</code>s into an array of
|
455 |
* <code>bytes</code>.
|
456 |
*
|
457 |
* @param dst the array to write
|
458 |
* @param dst_offset the start offset in <code>dst</code>
|
459 |
* @param src the array to read
|
460 |
* @param src_offset the start offset in <code>src</code>, times 4. This
|
461 |
* measures the offset as if <code>src</code> were an array of
|
462 |
* <code>byte</code>s (rather than <code>int</code>s).
|
463 |
* @param length the number of <code>byte</code>s to copy.
|
464 |
*/
|
465 |
public static final void intsToBytes(byte[] dst, int dst_offset, int[] src, |
466 |
int src_offset, int length) { |
467 |
if ((src == null) || (dst == null) || |
468 |
((dst_offset + length) > dst.length) || |
469 |
((src_offset + length) > (src.length * 4)) ||
|
470 |
((src_offset % 4) != 0) || ((length % 4) != 0)) { |
471 |
croak("intsToBytes parameters are invalid:" + " src=" + src + |
472 |
" dst=" + dst + " (dst_offset=" + dst_offset + " + length=" + |
473 |
length + ")=" + (dst_offset + length) + " > dst.length=" + |
474 |
((dst == null) ? 0 : dst.length) + " (src_offset=" + |
475 |
src_offset + " + length=" + length + ")=" + |
476 |
(src_offset + length) + " > (src.length=" +
|
477 |
((src == null) ? 0 : src.length) + "*4)=" + |
478 |
((src == null) ? 0 : (src.length * 4)) + " (src_offset=" + |
479 |
src_offset + " % 4)=" + (src_offset % 4) + " != 0" + |
480 |
" (length=" + length + " % 4)=" + (length % 4) + " != 0"); |
481 |
} |
482 |
|
483 |
// Convert parameters to normal format
|
484 |
int[] offset = new int[1]; |
485 |
offset[0] = dst_offset;
|
486 |
|
487 |
int int_src_offset = src_offset / 4; |
488 |
|
489 |
for (int i = 0; i < (length / 4); ++i) { |
490 |
intToBytes(src[int_src_offset++], dst, offset); |
491 |
} |
492 |
} |
493 |
|
494 |
/**
|
495 |
* Convert a <code>byte</code> into an unsigned integer.
|
496 |
*
|
497 |
* @param b the <code>byte</code> to cast
|
498 |
*
|
499 |
* @return a postiive <code>int</code> whose lowest byte contains the bits
|
500 |
* of <code>b</code>.
|
501 |
*/
|
502 |
public static final int byteToUnsignedInt(byte b) { |
503 |
return ((int) b) & 0xff; |
504 |
} |
505 |
|
506 |
/**
|
507 |
* Copy contents of one array of <code>bytes</code> into another. If either
|
508 |
* array is <code>null</code>, simply return the <code>length</code>
|
509 |
* parameter directly.
|
510 |
*
|
511 |
* @param dst the array to write, or <code>null</code>
|
512 |
* @param dst_offset the start offset in <code>dst</code>
|
513 |
* @param src the array to read, or <code>null</code>
|
514 |
* @param src_offset the start offset in <code>src</code>
|
515 |
* @param length the number of <code>byte</code>s to copy.
|
516 |
*
|
517 |
* @return DOCUMENT ME!
|
518 |
*/
|
519 |
public static int memcpy(byte[] dst, int dst_offset, byte[] src, |
520 |
int src_offset, int length) { |
521 |
if ((dst != null) && (src != null)) { |
522 |
if (dst.length < (dst_offset + length)) {
|
523 |
croak("dst.length = " + dst.length + ", but " + |
524 |
"dst_offset = " + dst_offset + " and length = " + length + |
525 |
".");
|
526 |
} |
527 |
|
528 |
if (src.length < (src_offset + length)) {
|
529 |
croak("src.length = " + src.length + ", but " + |
530 |
"src_offset = " + src_offset + " and length = " + length + |
531 |
".");
|
532 |
} |
533 |
|
534 |
for (int i = 0; i < length; ++i, ++dst_offset, ++src_offset) |
535 |
dst[dst_offset] = src[src_offset]; |
536 |
} |
537 |
|
538 |
return length;
|
539 |
} |
540 |
|
541 |
/**
|
542 |
* Compare the contents of one array of <code>bytes</code> to another.
|
543 |
*
|
544 |
* @param a the first array
|
545 |
* @param a_offset the start offset in <code>a</code>
|
546 |
* @param b the second array
|
547 |
* @param b_offset the start offset in <code>b</code>
|
548 |
* @param length the number of <code>byte</code>s to compare.
|
549 |
*
|
550 |
* @return DOCUMENT ME!
|
551 |
*/
|
552 |
public static boolean memcmp(byte[] a, int a_offset, byte[] b, |
553 |
int b_offset, int length) { |
554 |
if ((a == null) && (b == null)) { |
555 |
return true; |
556 |
} |
557 |
|
558 |
if ((a == null) || (b == null)) { |
559 |
return false; |
560 |
} |
561 |
|
562 |
for (int i = 0; i < length; ++i, ++a_offset, ++b_offset) |
563 |
if (a[a_offset] != b[b_offset]) {
|
564 |
return false; |
565 |
} |
566 |
|
567 |
return true; |
568 |
} |
569 |
|
570 |
/**
|
571 |
* Fill the given array with zeros.
|
572 |
*
|
573 |
* @param array the array to clear
|
574 |
* @param offset the start offset
|
575 |
* @param length the number of <code>byte</code>s to clear.
|
576 |
*/
|
577 |
public static void memclr(byte[] array, int offset, int length) { |
578 |
for (int i = 0; i < length; ++i, ++offset) |
579 |
array[offset] = 0;
|
580 |
} |
581 |
|
582 |
/**
|
583 |
* Round a number up to a given multiple.
|
584 |
*
|
585 |
* @param value the number to be rounded
|
586 |
* @param multiple the number to which to be rounded
|
587 |
*
|
588 |
* @return the smallest <code>int</code> greater than or equal to
|
589 |
* <code>value</code> which divides <code>multiple</code> exactly.
|
590 |
*/
|
591 |
public static int round_up(int value, int multiple) { |
592 |
return (((value - 1) / multiple) + 1) * multiple; |
593 |
} |
594 |
|
595 |
/**
|
596 |
* Return a new array equal to original except zero-padded to an integral
|
597 |
* mulitple of blocks. If the original is already an integral multiple of
|
598 |
* blocks, just return it.
|
599 |
*
|
600 |
* @param original the array of <code>byte</code>s to be padded
|
601 |
* @param block_size the size of the blocks
|
602 |
*
|
603 |
* @return an array whose size divides <code>block_size</code> exactly. The
|
604 |
* array is either <code>original</code> itself, or a copy whose
|
605 |
* first <code>original.length</code> bytes are equal to
|
606 |
* <code>original</code>.
|
607 |
*/
|
608 |
public static byte[] zero_pad(byte[] original, int block_size) { |
609 |
if ((original.length % block_size) == 0) { |
610 |
return original;
|
611 |
} |
612 |
|
613 |
byte[] result = new byte[round_up(original.length, block_size)]; |
614 |
memcpy(result, 0, original, 0, original.length); |
615 |
|
616 |
// Unnecessary - jvm sets bytes to 0.
|
617 |
// memclr (result, original.length, result.length - original.length);
|
618 |
return result;
|
619 |
} |
620 |
|
621 |
/**
|
622 |
* Determines whether two arrays of <code>byte</code>s contain the same
|
623 |
* contents.
|
624 |
*
|
625 |
* @param b1 The first array
|
626 |
* @param b2 The second array
|
627 |
*
|
628 |
* @return <code>true</code> if both arrays are <code>null</code>, both
|
629 |
* empty, or both of the same length with equal contents.
|
630 |
*/
|
631 |
public static boolean equals(byte[] b1, byte[] b2) { |
632 |
if (b1 == b2) {
|
633 |
return true; |
634 |
} |
635 |
|
636 |
if ((b1 == null) || (b2 == null)) { // only one is null |
637 |
|
638 |
return false; |
639 |
} |
640 |
|
641 |
if (b1.length != b2.length) {
|
642 |
return false; |
643 |
} |
644 |
|
645 |
for (int i = 0; i < b1.length; ++i) |
646 |
if (b1[i] != b2[i]) {
|
647 |
return false; |
648 |
} |
649 |
|
650 |
return true; |
651 |
} |
652 |
|
653 |
/**
|
654 |
* Produce a <code>String</code> representation for the specified array of
|
655 |
* <code>byte</code>s. Print each <code>byte</code> as two hexadecimal
|
656 |
* digits.
|
657 |
*
|
658 |
* @param data The array to print
|
659 |
* @param offset the start offset in <code>data</code>
|
660 |
* @param length the number of <code>byte</code>s to print
|
661 |
*
|
662 |
* @return DOCUMENT ME!
|
663 |
*/
|
664 |
public static String print_bytes(byte[] data, int offset, int length) { |
665 |
int size = 2 * length; |
666 |
size += ((size / 8) + (size / 64)); |
667 |
|
668 |
char[] buf = new char[size]; |
669 |
int low_mask = 0x0f; |
670 |
int high_mask = 0xf0; |
671 |
int buf_pos = 0; |
672 |
byte b;
|
673 |
|
674 |
int j = 0; |
675 |
|
676 |
for (int i = offset; i < (offset + length); ++i) { |
677 |
b = data[i]; |
678 |
buf[buf_pos++] = digits[(high_mask & b) >> 4];
|
679 |
buf[buf_pos++] = digits[(low_mask & b)]; |
680 |
|
681 |
if ((j % 4) == 3) { |
682 |
buf[buf_pos++] = ' ';
|
683 |
} |
684 |
|
685 |
if ((j % 32) == 31) { |
686 |
buf[buf_pos++] = '\n';
|
687 |
} |
688 |
|
689 |
++j; |
690 |
} |
691 |
|
692 |
return new String(buf); |
693 |
} |
694 |
|
695 |
/**
|
696 |
* DOCUMENT ME!
|
697 |
*
|
698 |
* @param data DOCUMENT ME!
|
699 |
* @param offset DOCUMENT ME!
|
700 |
* @param length DOCUMENT ME!
|
701 |
*
|
702 |
* @return DOCUMENT ME!
|
703 |
*/
|
704 |
public static String print_bytes_exact(byte[] data, int offset, int length) { |
705 |
int size = 2 * length; |
706 |
char[] buf = new char[size]; |
707 |
int low_mask = 0x0f; |
708 |
int high_mask = 0xf0; |
709 |
int buf_pos = 0; |
710 |
byte b;
|
711 |
|
712 |
int j = 0; |
713 |
|
714 |
for (int i = offset; i < (offset + length); ++i) { |
715 |
b = data[i]; |
716 |
buf[buf_pos++] = digits[(high_mask & b) >> 4];
|
717 |
buf[buf_pos++] = digits[(low_mask & b)]; |
718 |
++j; |
719 |
} |
720 |
|
721 |
return new String(buf); |
722 |
} |
723 |
|
724 |
/**
|
725 |
* DOCUMENT ME!
|
726 |
*
|
727 |
* @param data DOCUMENT ME!
|
728 |
*
|
729 |
* @return DOCUMENT ME!
|
730 |
*/
|
731 |
public static String print_bytes(byte[] data) { |
732 |
return print_bytes(data, 0, data.length); |
733 |
} |
734 |
|
735 |
/**
|
736 |
* DOCUMENT ME!
|
737 |
*
|
738 |
* @param msg DOCUMENT ME!
|
739 |
*/
|
740 |
private static void croak(String msg) { |
741 |
// throw new java.AssertionViolatedException(msg);
|
742 |
} |
743 |
|
744 |
/**
|
745 |
* DOCUMENT ME!
|
746 |
*
|
747 |
* @param b DOCUMENT ME!
|
748 |
*
|
749 |
* @return DOCUMENT ME!
|
750 |
*/
|
751 |
public static int getUnsigned(byte b) { |
752 |
return ((b & 0xff)); // >> 8); |
753 |
} |
754 |
} |