accountmanager.java

java 完全探索的随书源码

public class AccountManager {

  // account numbers are validated simply based on length
  private static int MIN_ACCOUNT_NUM_LENGTH = 8;
  private static int MAX_ACCOUNT_NUM_LENGTH = 9;

  public static boolean validAccountNumber(String accountNum) {
    // make sure length is ok
    if ( (accountNum.length() < MIN_ACCOUNT_NUM_LENGTH) ||
     (accountNum.length() > MAX_ACCOUNT_NUM_LENGTH) ) {
       return false;
    }

    // make sure every character is a digit
    for (int i=0; i<accountNum.length(); i++) {
      if ( !Character.isDigit( accountNum.charAt(i) ) ) {
        return false;
      }
    }
    // passed all the tests
    return true;
  }
}