/** * JWAP - A Java Implementation of the WAP Protocols * Copyright (C) 2001-2004 Niko Bender * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */package net.sourceforge.jwap.wsp.header;import java.util.Date;/** * This class contains static methods used to encode primitive data types used * for encoding WSP data units. * * @author Michel Marti * */public class Encoding {    private static final byte[] EMPTY_VALUE = new byte[0];    private static final byte[] EMPTY_STRING = new byte[] { 0 };    private Encoding() {    }    public static byte[] textString(String value) {        byte[] data = null;        if (value == null ) {            data = EMPTY_VALUE;        } else if( "".equals(value) ) {            data = EMPTY_STRING;        } else {            byte[] b = value.getBytes();            if (b[0] > 127) {                data = new byte[b.length + 2];                data[0] = 127;                System.arraycopy(b, 0, data, 1, b.length);            } else {                data = new byte[b.length + 1];                System.arraycopy(b, 0, data, 0, b.length);            }        }        return data;    }    public static byte[] extensionMedia(String value) {        byte[] data = null;        if (value == null) {            data = EMPTY_VALUE;        } else {            byte[] b = value.getBytes();            data = new byte[b.length + 1];            System.arraycopy(b, 0, data, 0, b.length);        }        return data;    }    public static byte[] tokenText(String value) {        int len = 1;        byte[] data = null;        if (value != null) {            len += value.length();            data = new byte[len];            byte[] sb = value.getBytes();            System.arraycopy(sb, 0, data, 0, len - 1);        } else {            data = EMPTY_STRING;        }        return data;    }    public static byte[] shortInteger(short value) {        byte[] data = null;        data = new byte[1];        data[0] = (byte) ((Math.abs(value) & 0xff) | 0x80);        return data;    }    public static byte[] longInteger(long value) {        byte[] data = null;        value = Math.abs(value);        int octets = (int) Math.ceil(Long.toBinaryString(value).length() / 8.0);        data = new byte[octets + 1];        data[0] = (byte) octets;        while (octets > 0) {            data[octets] = (byte) (value & 0xff);            value >>= 8;            octets--;        }        return data;    }    public static byte[] uintVar(int value) {        byte[] data = null;        byte[] b = new byte[5];        int i = 5;        do {            int x = value & 0x7f;            value >>= 7;            if (i != 5) {                x |= 0x80;            }            b[--i] = (byte) (x & 0xff);        } while ((value > 0) && (i > 0));        data = new byte[5 - i];        System.arraycopy(b, i, data, 0, data.length);        return data;    }    public static byte[] quotedString(String value) {        byte[] data = null;        if (value == null) {            data = new byte[] { 0x22, 0x00 };        } else {            byte[] b = value.getBytes();            data = new byte[b.length + 2];            data[0] = 0x22;            System.arraycopy(b, 0, data, 1, b.length);        }        return data;    }    public static byte[] dateValue(Date date) {        long secs = date.getTime() / 1000;        return longInteger(secs);    }    public static byte[] qualityFactor(float value) {        int qf = (int) (value * 1000) % 1000;        if ((qf % 10) != 0) {            qf += 100;        } else {            qf = (qf / 10) + 1;        }        return uintVar(qf);    }    public static byte[] versionValue(String version) {        // TODO: Try to extract major and minor from string so that        // a shortInteger can be used instead of a text-string...        return textString(version);    }    public static byte[] versionValue(int major, int minor) {        if ((major < 1) || (major > 7) || (minor < 0) || (minor > 14)) {            StringBuffer sb = new StringBuffer(major).append('.').append(minor);            return textString(sb.toString());        }        if (minor == 0) {            minor = 15;        }        short i = (short) (((major & 0x0F) << 8) | (minor & 0x0f));        return shortInteger(i);    }    public static byte[] valueLength(byte[] tt) {        return valueLength((tt == null) ? 0 : tt.length);    }    public static byte[] valueLength(int i) {        byte[] ret = null;        if (i == 0) {            ret = EMPTY_VALUE;        } else if (i <= 30) {            ret = new byte[] { (byte) i };        } else {            byte[] ui = uintVar(i);            ret = new byte[ui.length + 1];            ret[0] = 31;            System.arraycopy(ui, 0, ret, 1, ui.length);        }        return ret;    }    public static byte[] encodeHeader(short wk, byte[] data) {        byte[] kb = shortInteger(wk);        byte[] ret = new byte[data.length + kb.length];        System.arraycopy(kb, 0, ret, 0, kb.length);        System.arraycopy(data, 0, ret, kb.length, data.length);        return ret;    }    public static byte[] encodeHeader(String key, byte[] data) {        byte[] kb = textString(key);        byte[] ret = new byte[kb.length + data.length];        System.arraycopy(kb, 0, ret, 0, kb.length);        System.arraycopy(data, 0, ret, kb.length, data.length);        return ret;    }    public static byte[] integerValue(long l) {        return (l < 0x80) ? Encoding.shortInteger((short) l)                          : Encoding.longInteger(l);    }    public static byte[] uriValue(String value) {        return textString((value == null) ? null : value.trim());    }}