Java随机生成信用卡卡号的代码

import java.util.List; import java.util.Stack; import java.util.Vector; /** * See the license below. Obviously, this is not a Javascript credit card number * generator. However, The following class is a port of a Javascript credit card * number generator. * * @author robweber * */ public class RandomCreditCardNumberGenerator { /* * Javascript credit card number generator Copyright (C) 2006-2012 Graham King * * 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., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * www.darkcoding.net */public static final String[] VISA_PREFIX_LIST = new String[] { "4539", "4556", "4916", "4532", "4929", "40240071", "4485", "4716", "4" }; public static final String[] MASTERCARD_PREFIX_LIST = new String[] { "51", "52", "53", "54", "55" }; public static final String[] AMEX_PREFIX_LIST = new String[] { "34", "37" }; public static final String[] DISCOVER_PREFIX_LIST = new String[] { "6011" }; public static final String[] DINERS_PREFIX_LIST = new String[] { "300", "301", "302", "303", "36", "38" }; public static final String[] ENROUTE_PREFIX_LIST = new String[] { "2014", "2149" }; public static final String[] JCB_PREFIX_LIST = new String[] { "35" }; public static final String[] VOYAGER_PREFIX_LIST = new String[] { "8699" }; static String strrev(String str) { if (str == null) return ""; String revstr = ""; for (int i = str.length() - 1; i >= 0; i--) { revstr += str.charAt(i); }return revstr; }/* * 'prefix' is the start of the CC number as a string, any number of digits. * 'length' is the length of the CC number to generate. Typically 13 or 16 */ static String completed_number(String prefix, int length) {String ccnumber = prefix; // generate digitswhile (ccnumber.length() < (length - 1)) { ccnumber += new Double(Math.floor(Math.random() * 10)).intValue(); }// reverse number and convert to intString reversedCCnumberString = strrev(ccnumber); List reversedCCnumberList = new Vector(); for (int i = 0; i < reversedCCnumberString.length(); i++) { reversedCCnumberList.add(new Integer(String .valueOf(reversedCCnumberString.charAt(i)))); }// calculate sumint sum = 0; int pos = 0; Integer[] reversedCCnumber = reversedCCnumberList .toArray(new Integer[reversedCCnumberList.size()]); while (pos < length - 1) {int odd = reversedCCnumber[pos] * 2; if (odd > 9) { odd -= 9; }sum += odd; if (pos != (length - 2)) { sum += reversedCCnumber[pos + 1]; } pos += 2; }// calculate check digitint checkdigit = new Double( ((Math.floor(sum / 10) + 1) * 10 - sum) % 10).intValue(); ccnumber += checkdigit; return ccnumber; }public static String[] credit_card_number(String[] prefixList, int length, int howMany) {Stack result = new Stack(); for (int i = 0; i < howMany; i++) { int randomArrayIndex = (int) Math.floor(Math.random() * prefixList.length); String ccnumber = prefixList[randomArrayIndex]; result.push(completed_number(ccnumber, length)); }return result.toArray(new String[result.size()]); }public static String[] generateMasterCardNumbers(int howMany) { return credit_card_number(MASTERCARD_PREFIX_LIST, 16, howMany); }public static String generateMasterCardNumber() { return credit_card_number(MASTERCARD_PREFIX_LIST, 16, 1)[0]; }public static boolean isValidCreditCardNumber(String creditCardNumber) { boolean isValid = false; try { String reversedNumber = new StringBuffer(creditCardNumber) .reverse().toString(); int mod10Count = 0; for (int i = 0; i < reversedNumber.length(); i++) { int augend = Integer.parseInt(String.valueOf(reversedNumber .charAt(i))); if (((i + 1) % 2) == 0) { String productString = String.valueOf(augend * 2); augend = 0; for (int j = 0; j < productString.length(); j++) { augend += Integer.parseInt(String.valueOf(productString .charAt(j))); } }mod10Count += augend; }if ((mod10Count % 10) == 0) { isValid = true; } } catch (NumberFormatException e) { }return isValid; }public static void main(String[] args) { int howMany = 0; try { howMany = Integer.parseInt(args[0]); } catch (Exception e) { System.err .println("Usage error. You need to supply a numeric argument (ex: 500000)"); } String[] creditcardnumbers = generateMasterCardNumbers(howMany); for (int i = 0; i < creditcardnumbers.length; i++) { System.out.println(creditcardnumbers[i] + ":" + (isValidCreditCardNumber(creditcardnumbers[i]) ? "valid" : "invalid")); } } } //该代码片段来自于: http://www.sharejs.com/codes/java/7103

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