Here you can find the source of toBase64(long num)
Encode number to base64 (based on http://www.ietf.org/rfc/rfc2045.txt Table 1)
| Parameter | Description |
|---|---|
| num | Number to convert |
public static String toBase64(long num)
//package com.java2s; /*/*ww w .j a v a 2s. c om*/ * ==================================================================== * JAFFA - Java Application Framework For All * * Copyright (C) 2002 JAFFA Development Group * * 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 * * Redistribution and use of this software and associated documentation ("Software"), * with or without modification, are permitted provided that the following conditions are met: * 1. Redistributions of source code must retain copyright statements and notices. * Redistributions must also contain a copy of this document. * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * 3. The name "JAFFA" must not be used to endorse or promote products derived from * this Software without prior written permission. For written permission, * please contact mail to: jaffagroup@yahoo.com. * 4. Products derived from this Software may not be called "JAFFA" nor may "JAFFA" * appear in their names without prior written permission. * 5. Due credit should be given to the JAFFA Project (http://jaffa.sourceforge.net). * * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ==================================================================== */ public class Main { /** * Characters used for Base 64 encoding * (See http://www.ietf.org/rfc/rfc2045.txt Table 1) */ public static final String BASE64_CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; /** * Encode number to base64 (based on http://www.ietf.org/rfc/rfc2045.txt Table 1) * @param num Number to convert * @return encoded value as a string */ public static String toBase64(long num) { return toBase(num, BASE64_CHARS); } /** * Encode number to any base * @param num Number to convert * @param baseChars Alphabet of characters used to decode. Size of string implies base, * ie "01" would be binary (base 2) * @return encoded value as a string */ public static String toBase(long num, String baseChars) { int base = baseChars.length(); if (num < 0) throw new RuntimeException("toBase() only works for positive integers"); if (num == 0) return "" + baseChars.charAt(0); StringBuffer sb = new StringBuffer(); for (; num > 0;) { int mod = (int) (num % base); if (mod < 0) System.out.println(num + "%" + base + "=" + mod); sb.append(baseChars.charAt(mod)); num = num / base; } sb.reverse(); return sb.toString(); } }