ByteFormatter.java

/*
 * Created on 2 juil. 2003
 * Copyright (C) 2003, 2004, 2005, 2006 Aelitis, All Rights Reserved.
 *
 * This program 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.
 * 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 General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * AELITIS, SAS au capital de 46,603.30 euros
 * 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
 *
 */
package com.frostwire.torrent;

/**
 * @author Olivier
 * 
 */

import java.nio.ByteBuffer;

final class ByteFormatter {
    final static char[] HEXDIGITS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

    public static String nicePrint(String str) {
        return (nicePrint(str.getBytes(), true));
    }

    public static String nicePrint(byte[] data) {
        return (nicePrint(data, false));
    }

    public static String nicePrint(byte[] data, int max) {
        return (nicePrint(data, false, max));
    }

    public static String nicePrint(ByteBuffer data) {
        byte[] raw = new byte[data.limit()];

        for (int i = 0; i < raw.length; i++) {
            raw[i] = data.get(i);
        }

        return nicePrint(raw);
    }

    public static String nicePrint(byte[] data, boolean tight) {
        return (nicePrint(data, tight, 1024));
    }

    public static String nicePrint(byte[] data, boolean tight, int max_length) {
        if (data == null) {
            return "";
        }

        int dataLength = data.length;

        if (dataLength > max_length) {
            dataLength = max_length;
        }

        int size = dataLength * 2;
        if (!tight) {
            size += (dataLength - 1) / 4;
        }

        char[] out = new char[size];

        try {
            int pos = 0;
            for (int i = 0; i < dataLength; i++) {
                if ((!tight) && (i % 4 == 0) && i > 0) {
                    out[pos++] = ' ';
                }

                out[pos++] = HEXDIGITS[(byte) ((data[i] >> 4) & 0xF)];
                out[pos++] = HEXDIGITS[(byte) (data[i] & 0xF)];
            }

        } catch (Exception e) {
            Debug.printStackTrace(e);
        }

        try {
            return new String(out) + (data.length > max_length ? "..." : "");
        } catch (Exception e) {
            Debug.printStackTrace(e);
        }

        return "";
    }

    public static String nicePrint(byte b) {
        byte b1 = (byte) ((b >> 4) & 0x0000000F);
        byte b2 = (byte) (b & 0x0000000F);
        return nicePrint2(b1) + nicePrint2(b2);
    }

    public static String nicePrint2(byte b) {
        String out = "";
        switch (b) {
        case 0:
            out = "0";
            break;
        case 1:
            out = "1";
            break;
        case 2:
            out = "2";
            break;
        case 3:
            out = "3";
            break;
        case 4:
            out = "4";
            break;
        case 5:
            out = "5";
            break;
        case 6:
            out = "6";
            break;
        case 7:
            out = "7";
            break;
        case 8:
            out = "8";
            break;
        case 9:
            out = "9";
            break;
        case 10:
            out = "A";
            break;
        case 11:
            out = "B";
            break;
        case 12:
            out = "C";
            break;
        case 13:
            out = "D";
            break;
        case 14:
            out = "E";
            break;
        case 15:
            out = "F";
            break;
        }
        return out;
    }

    /**
     * Note this has a truncation limit at 1024 chars....
     * @param bytes
     * @return
     */
    public static String encodeString(byte[] bytes) {
        return (nicePrint(bytes, true));
    }

    public static String encodeString(byte[] bytes, int offset, int len) {
        byte[] x = new byte[len];

        System.arraycopy(bytes, offset, x, 0, len);

        return (nicePrint(x, true));
    }

    public static byte[] decodeString(String str) {
        char[] chars = str.toCharArray();

        int chars_length = chars.length - chars.length % 2;

        byte[] res = new byte[chars_length / 2];

        for (int i = 0; i < chars_length; i += 2) {

            String b = new String(chars, i, 2);

            res[i / 2] = (byte) Integer.parseInt(b, 16);
        }

        return (res);
    }
}