java检测isbn是否合法，java检测isbn合法,/** * An IS

java检测isbn是否合法，java检测isbn合法,/** * An IS

/**  * An ISBN Utility  * @author Julius Schorzman  * (C) 2006 -- Provided under GPL  */  public class ISBNUtil {      /**      * Checks if the passed string is a valid ISBN number.      * @param isbn The ISBN String      * @return true if it is a valid isbn; false in all other cases.      */      public static boolean isISBN(String isbn) {          try {              if (isbn.length() != 10) {                  return false;              }              int weight = 10;              int rollingSum = 0;              for ( int i = 0 ; i < 9 ; i++ ) {                  int isbnDigit = Character.digit(isbn.charAt(i), 10);                  rollingSum += isbnDigit * weight--;              }              int mod = rollingSum % 11;              mod = 11 - mod;              if ( mod == 11 ) mod = 0;              char checkSum = isbn.charAt(9);              if (Character.toLowerCase(checkSum) == 'x') {                  if ( mod == 10 ) return true;              } else {                  if (Character.digit(checkSum, 10) == mod) return true;              }              return false;          } catch (Exception e) {              return false;          }      }      public static void main(String[] args) {          System.out.println("true: "+ISBNUtil.isISBN("031234161X"));          System.out.println("true: "+ISBNUtil.isISBN("0525949488"));          System.out.println("true: "+ISBNUtil.isISBN("076360013X"));          System.out.println("true: "+ISBNUtil.isISBN("0671027360"));          System.out.println("true: "+ISBNUtil.isISBN("0803612079"));          System.out.println("true: "+ISBNUtil.isISBN("0307263118"));          System.out.println("true: "+ISBNUtil.isISBN("0684856093"));          System.out.println("true: "+ISBNUtil.isISBN("0767916565"));          System.out.println("true: "+ISBNUtil.isISBN("0071392319"));          System.out.println("true: "+ISBNUtil.isISBN("1400032806"));          System.out.println("true: "+ISBNUtil.isISBN("0765305240"));          System.out.println("false: "+ISBNUtil.isISBN("0312341613"));          System.out.println("false: "+ISBNUtil.isISBN("052594948X"));          System.out.println("false: "+ISBNUtil.isISBN("0763600138"));          System.out.println("false: "+ISBNUtil.isISBN("0671027364"));          System.out.println("false: "+ISBNUtil.isISBN("080361207X"));          System.out.println("false: "+ISBNUtil.isISBN("0307263110"));          System.out.println("false: "+ISBNUtil.isISBN("0684856092"));          System.out.println("false: "+ISBNUtil.isISBN("0767916567"));          System.out.println("false: "+ISBNUtil.isISBN("0071392318"));          System.out.println("false: "+ISBNUtil.isISBN("1400032801"));          System.out.println("false: "+ISBNUtil.isISBN("0765305241"));      }  }